1 | // SPDX-License-Identifier: GPL-2.0-only |
2 | /* |
3 | * Security-Enhanced Linux (SELinux) security module |
4 | * |
5 | * This file contains the SELinux hook function implementations. |
6 | * |
7 | * Authors: Stephen Smalley, <stephen.smalley.work@gmail.com> |
8 | * Chris Vance, <cvance@nai.com> |
9 | * Wayne Salamon, <wsalamon@nai.com> |
10 | * James Morris <jmorris@redhat.com> |
11 | * |
12 | * Copyright (C) 2001,2002 Networks Associates Technology, Inc. |
13 | * Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com> |
14 | * Eric Paris <eparis@redhat.com> |
15 | * Copyright (C) 2004-2005 Trusted Computer Solutions, Inc. |
16 | * <dgoeddel@trustedcs.com> |
17 | * Copyright (C) 2006, 2007, 2009 Hewlett-Packard Development Company, L.P. |
18 | * Paul Moore <paul@paul-moore.com> |
19 | * Copyright (C) 2007 Hitachi Software Engineering Co., Ltd. |
20 | * Yuichi Nakamura <ynakam@hitachisoft.jp> |
21 | * Copyright (C) 2016 Mellanox Technologies |
22 | */ |
23 | |
24 | #include <linux/init.h> |
25 | #include <linux/kd.h> |
26 | #include <linux/kernel.h> |
27 | #include <linux/kernel_read_file.h> |
28 | #include <linux/errno.h> |
29 | #include <linux/sched/signal.h> |
30 | #include <linux/sched/task.h> |
31 | #include <linux/lsm_hooks.h> |
32 | #include <linux/xattr.h> |
33 | #include <linux/capability.h> |
34 | #include <linux/unistd.h> |
35 | #include <linux/mm.h> |
36 | #include <linux/mman.h> |
37 | #include <linux/slab.h> |
38 | #include <linux/pagemap.h> |
39 | #include <linux/proc_fs.h> |
40 | #include <linux/swap.h> |
41 | #include <linux/spinlock.h> |
42 | #include <linux/syscalls.h> |
43 | #include <linux/dcache.h> |
44 | #include <linux/file.h> |
45 | #include <linux/fdtable.h> |
46 | #include <linux/namei.h> |
47 | #include <linux/mount.h> |
48 | #include <linux/fs_context.h> |
49 | #include <linux/fs_parser.h> |
50 | #include <linux/netfilter_ipv4.h> |
51 | #include <linux/netfilter_ipv6.h> |
52 | #include <linux/tty.h> |
53 | #include <net/icmp.h> |
54 | #include <net/ip.h> /* for local_port_range[] */ |
55 | #include <net/tcp.h> /* struct or_callable used in sock_rcv_skb */ |
56 | #include <net/inet_connection_sock.h> |
57 | #include <net/net_namespace.h> |
58 | #include <net/netlabel.h> |
59 | #include <linux/uaccess.h> |
60 | #include <asm/ioctls.h> |
61 | #include <linux/atomic.h> |
62 | #include <linux/bitops.h> |
63 | #include <linux/interrupt.h> |
64 | #include <linux/netdevice.h> /* for network interface checks */ |
65 | #include <net/netlink.h> |
66 | #include <linux/tcp.h> |
67 | #include <linux/udp.h> |
68 | #include <linux/dccp.h> |
69 | #include <linux/sctp.h> |
70 | #include <net/sctp/structs.h> |
71 | #include <linux/quota.h> |
72 | #include <linux/un.h> /* for Unix socket types */ |
73 | #include <net/af_unix.h> /* for Unix socket types */ |
74 | #include <linux/parser.h> |
75 | #include <linux/nfs_mount.h> |
76 | #include <net/ipv6.h> |
77 | #include <linux/hugetlb.h> |
78 | #include <linux/personality.h> |
79 | #include <linux/audit.h> |
80 | #include <linux/string.h> |
81 | #include <linux/mutex.h> |
82 | #include <linux/posix-timers.h> |
83 | #include <linux/syslog.h> |
84 | #include <linux/user_namespace.h> |
85 | #include <linux/export.h> |
86 | #include <linux/msg.h> |
87 | #include <linux/shm.h> |
88 | #include <linux/bpf.h> |
89 | #include <linux/kernfs.h> |
90 | #include <linux/stringhash.h> /* for hashlen_string() */ |
91 | #include <uapi/linux/mount.h> |
92 | #include <linux/fsnotify.h> |
93 | #include <linux/fanotify.h> |
94 | #include <linux/io_uring.h> |
95 | |
96 | #include "avc.h" |
97 | #include "objsec.h" |
98 | #include "netif.h" |
99 | #include "netnode.h" |
100 | #include "netport.h" |
101 | #include "ibpkey.h" |
102 | #include "xfrm.h" |
103 | #include "netlabel.h" |
104 | #include "audit.h" |
105 | #include "avc_ss.h" |
106 | |
107 | #define SELINUX_INODE_INIT_XATTRS 1 |
108 | |
109 | struct selinux_state selinux_state; |
110 | |
111 | /* SECMARK reference count */ |
112 | static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0); |
113 | |
114 | #ifdef CONFIG_SECURITY_SELINUX_DEVELOP |
115 | static int selinux_enforcing_boot __initdata; |
116 | |
117 | static int __init enforcing_setup(char *str) |
118 | { |
119 | unsigned long enforcing; |
120 | if (!kstrtoul(s: str, base: 0, res: &enforcing)) |
121 | selinux_enforcing_boot = enforcing ? 1 : 0; |
122 | return 1; |
123 | } |
124 | __setup("enforcing=" , enforcing_setup); |
125 | #else |
126 | #define selinux_enforcing_boot 1 |
127 | #endif |
128 | |
129 | int selinux_enabled_boot __initdata = 1; |
130 | #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM |
131 | static int __init selinux_enabled_setup(char *str) |
132 | { |
133 | unsigned long enabled; |
134 | if (!kstrtoul(s: str, base: 0, res: &enabled)) |
135 | selinux_enabled_boot = enabled ? 1 : 0; |
136 | return 1; |
137 | } |
138 | __setup("selinux=" , selinux_enabled_setup); |
139 | #endif |
140 | |
141 | static int __init checkreqprot_setup(char *str) |
142 | { |
143 | unsigned long checkreqprot; |
144 | |
145 | if (!kstrtoul(s: str, base: 0, res: &checkreqprot)) { |
146 | if (checkreqprot) |
147 | pr_err("SELinux: checkreqprot set to 1 via kernel parameter. This is no longer supported.\n" ); |
148 | } |
149 | return 1; |
150 | } |
151 | __setup("checkreqprot=" , checkreqprot_setup); |
152 | |
153 | /** |
154 | * selinux_secmark_enabled - Check to see if SECMARK is currently enabled |
155 | * |
156 | * Description: |
157 | * This function checks the SECMARK reference counter to see if any SECMARK |
158 | * targets are currently configured, if the reference counter is greater than |
159 | * zero SECMARK is considered to be enabled. Returns true (1) if SECMARK is |
160 | * enabled, false (0) if SECMARK is disabled. If the always_check_network |
161 | * policy capability is enabled, SECMARK is always considered enabled. |
162 | * |
163 | */ |
164 | static int selinux_secmark_enabled(void) |
165 | { |
166 | return (selinux_policycap_alwaysnetwork() || |
167 | atomic_read(v: &selinux_secmark_refcount)); |
168 | } |
169 | |
170 | /** |
171 | * selinux_peerlbl_enabled - Check to see if peer labeling is currently enabled |
172 | * |
173 | * Description: |
174 | * This function checks if NetLabel or labeled IPSEC is enabled. Returns true |
175 | * (1) if any are enabled or false (0) if neither are enabled. If the |
176 | * always_check_network policy capability is enabled, peer labeling |
177 | * is always considered enabled. |
178 | * |
179 | */ |
180 | static int selinux_peerlbl_enabled(void) |
181 | { |
182 | return (selinux_policycap_alwaysnetwork() || |
183 | netlbl_enabled() || selinux_xfrm_enabled()); |
184 | } |
185 | |
186 | static int selinux_netcache_avc_callback(u32 event) |
187 | { |
188 | if (event == AVC_CALLBACK_RESET) { |
189 | sel_netif_flush(); |
190 | sel_netnode_flush(); |
191 | sel_netport_flush(); |
192 | synchronize_net(); |
193 | } |
194 | return 0; |
195 | } |
196 | |
197 | static int selinux_lsm_notifier_avc_callback(u32 event) |
198 | { |
199 | if (event == AVC_CALLBACK_RESET) { |
200 | sel_ib_pkey_flush(); |
201 | call_blocking_lsm_notifier(event: LSM_POLICY_CHANGE, NULL); |
202 | } |
203 | |
204 | return 0; |
205 | } |
206 | |
207 | /* |
208 | * initialise the security for the init task |
209 | */ |
210 | static void cred_init_security(void) |
211 | { |
212 | struct task_security_struct *tsec; |
213 | |
214 | tsec = selinux_cred(unrcu_pointer(current->real_cred)); |
215 | tsec->osid = tsec->sid = SECINITSID_KERNEL; |
216 | } |
217 | |
218 | /* |
219 | * get the security ID of a set of credentials |
220 | */ |
221 | static inline u32 cred_sid(const struct cred *cred) |
222 | { |
223 | const struct task_security_struct *tsec; |
224 | |
225 | tsec = selinux_cred(cred); |
226 | return tsec->sid; |
227 | } |
228 | |
229 | static void __ad_net_init(struct common_audit_data *ad, |
230 | struct lsm_network_audit *net, |
231 | int ifindex, struct sock *sk, u16 family) |
232 | { |
233 | ad->type = LSM_AUDIT_DATA_NET; |
234 | ad->u.net = net; |
235 | net->netif = ifindex; |
236 | net->sk = sk; |
237 | net->family = family; |
238 | } |
239 | |
240 | static void ad_net_init_from_sk(struct common_audit_data *ad, |
241 | struct lsm_network_audit *net, |
242 | struct sock *sk) |
243 | { |
244 | __ad_net_init(ad, net, ifindex: 0, sk, family: 0); |
245 | } |
246 | |
247 | static void ad_net_init_from_iif(struct common_audit_data *ad, |
248 | struct lsm_network_audit *net, |
249 | int ifindex, u16 family) |
250 | { |
251 | __ad_net_init(ad, net, ifindex, NULL, family); |
252 | } |
253 | |
254 | /* |
255 | * get the objective security ID of a task |
256 | */ |
257 | static inline u32 task_sid_obj(const struct task_struct *task) |
258 | { |
259 | u32 sid; |
260 | |
261 | rcu_read_lock(); |
262 | sid = cred_sid(__task_cred(task)); |
263 | rcu_read_unlock(); |
264 | return sid; |
265 | } |
266 | |
267 | static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry); |
268 | |
269 | /* |
270 | * Try reloading inode security labels that have been marked as invalid. The |
271 | * @may_sleep parameter indicates when sleeping and thus reloading labels is |
272 | * allowed; when set to false, returns -ECHILD when the label is |
273 | * invalid. The @dentry parameter should be set to a dentry of the inode. |
274 | */ |
275 | static int __inode_security_revalidate(struct inode *inode, |
276 | struct dentry *dentry, |
277 | bool may_sleep) |
278 | { |
279 | struct inode_security_struct *isec = selinux_inode(inode); |
280 | |
281 | might_sleep_if(may_sleep); |
282 | |
283 | if (selinux_initialized() && |
284 | isec->initialized != LABEL_INITIALIZED) { |
285 | if (!may_sleep) |
286 | return -ECHILD; |
287 | |
288 | /* |
289 | * Try reloading the inode security label. This will fail if |
290 | * @opt_dentry is NULL and no dentry for this inode can be |
291 | * found; in that case, continue using the old label. |
292 | */ |
293 | inode_doinit_with_dentry(inode, opt_dentry: dentry); |
294 | } |
295 | return 0; |
296 | } |
297 | |
298 | static struct inode_security_struct *inode_security_novalidate(struct inode *inode) |
299 | { |
300 | return selinux_inode(inode); |
301 | } |
302 | |
303 | static struct inode_security_struct *inode_security_rcu(struct inode *inode, bool rcu) |
304 | { |
305 | int error; |
306 | |
307 | error = __inode_security_revalidate(inode, NULL, may_sleep: !rcu); |
308 | if (error) |
309 | return ERR_PTR(error); |
310 | return selinux_inode(inode); |
311 | } |
312 | |
313 | /* |
314 | * Get the security label of an inode. |
315 | */ |
316 | static struct inode_security_struct *inode_security(struct inode *inode) |
317 | { |
318 | __inode_security_revalidate(inode, NULL, may_sleep: true); |
319 | return selinux_inode(inode); |
320 | } |
321 | |
322 | static struct inode_security_struct *backing_inode_security_novalidate(struct dentry *dentry) |
323 | { |
324 | struct inode *inode = d_backing_inode(upper: dentry); |
325 | |
326 | return selinux_inode(inode); |
327 | } |
328 | |
329 | /* |
330 | * Get the security label of a dentry's backing inode. |
331 | */ |
332 | static struct inode_security_struct *backing_inode_security(struct dentry *dentry) |
333 | { |
334 | struct inode *inode = d_backing_inode(upper: dentry); |
335 | |
336 | __inode_security_revalidate(inode, dentry, may_sleep: true); |
337 | return selinux_inode(inode); |
338 | } |
339 | |
340 | static void inode_free_security(struct inode *inode) |
341 | { |
342 | struct inode_security_struct *isec = selinux_inode(inode); |
343 | struct superblock_security_struct *sbsec; |
344 | |
345 | if (!isec) |
346 | return; |
347 | sbsec = selinux_superblock(inode->i_sb); |
348 | /* |
349 | * As not all inode security structures are in a list, we check for |
350 | * empty list outside of the lock to make sure that we won't waste |
351 | * time taking a lock doing nothing. |
352 | * |
353 | * The list_del_init() function can be safely called more than once. |
354 | * It should not be possible for this function to be called with |
355 | * concurrent list_add(), but for better safety against future changes |
356 | * in the code, we use list_empty_careful() here. |
357 | */ |
358 | if (!list_empty_careful(head: &isec->list)) { |
359 | spin_lock(lock: &sbsec->isec_lock); |
360 | list_del_init(entry: &isec->list); |
361 | spin_unlock(lock: &sbsec->isec_lock); |
362 | } |
363 | } |
364 | |
365 | struct selinux_mnt_opts { |
366 | u32 fscontext_sid; |
367 | u32 context_sid; |
368 | u32 rootcontext_sid; |
369 | u32 defcontext_sid; |
370 | }; |
371 | |
372 | static void selinux_free_mnt_opts(void *mnt_opts) |
373 | { |
374 | kfree(objp: mnt_opts); |
375 | } |
376 | |
377 | enum { |
378 | Opt_error = -1, |
379 | Opt_context = 0, |
380 | Opt_defcontext = 1, |
381 | Opt_fscontext = 2, |
382 | Opt_rootcontext = 3, |
383 | Opt_seclabel = 4, |
384 | }; |
385 | |
386 | #define A(s, has_arg) {#s, sizeof(#s) - 1, Opt_##s, has_arg} |
387 | static const struct { |
388 | const char *name; |
389 | int len; |
390 | int opt; |
391 | bool has_arg; |
392 | } tokens[] = { |
393 | A(context, true), |
394 | A(fscontext, true), |
395 | A(defcontext, true), |
396 | A(rootcontext, true), |
397 | A(seclabel, false), |
398 | }; |
399 | #undef A |
400 | |
401 | static int match_opt_prefix(char *s, int l, char **arg) |
402 | { |
403 | int i; |
404 | |
405 | for (i = 0; i < ARRAY_SIZE(tokens); i++) { |
406 | size_t len = tokens[i].len; |
407 | if (len > l || memcmp(p: s, q: tokens[i].name, size: len)) |
408 | continue; |
409 | if (tokens[i].has_arg) { |
410 | if (len == l || s[len] != '=') |
411 | continue; |
412 | *arg = s + len + 1; |
413 | } else if (len != l) |
414 | continue; |
415 | return tokens[i].opt; |
416 | } |
417 | return Opt_error; |
418 | } |
419 | |
420 | #define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n" |
421 | |
422 | static int may_context_mount_sb_relabel(u32 sid, |
423 | struct superblock_security_struct *sbsec, |
424 | const struct cred *cred) |
425 | { |
426 | const struct task_security_struct *tsec = selinux_cred(cred); |
427 | int rc; |
428 | |
429 | rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, |
430 | FILESYSTEM__RELABELFROM, NULL); |
431 | if (rc) |
432 | return rc; |
433 | |
434 | rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM, |
435 | FILESYSTEM__RELABELTO, NULL); |
436 | return rc; |
437 | } |
438 | |
439 | static int may_context_mount_inode_relabel(u32 sid, |
440 | struct superblock_security_struct *sbsec, |
441 | const struct cred *cred) |
442 | { |
443 | const struct task_security_struct *tsec = selinux_cred(cred); |
444 | int rc; |
445 | rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, |
446 | FILESYSTEM__RELABELFROM, NULL); |
447 | if (rc) |
448 | return rc; |
449 | |
450 | rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, |
451 | FILESYSTEM__ASSOCIATE, NULL); |
452 | return rc; |
453 | } |
454 | |
455 | static int selinux_is_genfs_special_handling(struct super_block *sb) |
456 | { |
457 | /* Special handling. Genfs but also in-core setxattr handler */ |
458 | return !strcmp(sb->s_type->name, "sysfs" ) || |
459 | !strcmp(sb->s_type->name, "pstore" ) || |
460 | !strcmp(sb->s_type->name, "debugfs" ) || |
461 | !strcmp(sb->s_type->name, "tracefs" ) || |
462 | !strcmp(sb->s_type->name, "rootfs" ) || |
463 | (selinux_policycap_cgroupseclabel() && |
464 | (!strcmp(sb->s_type->name, "cgroup" ) || |
465 | !strcmp(sb->s_type->name, "cgroup2" ))); |
466 | } |
467 | |
468 | static int selinux_is_sblabel_mnt(struct super_block *sb) |
469 | { |
470 | struct superblock_security_struct *sbsec = selinux_superblock(sb); |
471 | |
472 | /* |
473 | * IMPORTANT: Double-check logic in this function when adding a new |
474 | * SECURITY_FS_USE_* definition! |
475 | */ |
476 | BUILD_BUG_ON(SECURITY_FS_USE_MAX != 7); |
477 | |
478 | switch (sbsec->behavior) { |
479 | case SECURITY_FS_USE_XATTR: |
480 | case SECURITY_FS_USE_TRANS: |
481 | case SECURITY_FS_USE_TASK: |
482 | case SECURITY_FS_USE_NATIVE: |
483 | return 1; |
484 | |
485 | case SECURITY_FS_USE_GENFS: |
486 | return selinux_is_genfs_special_handling(sb); |
487 | |
488 | /* Never allow relabeling on context mounts */ |
489 | case SECURITY_FS_USE_MNTPOINT: |
490 | case SECURITY_FS_USE_NONE: |
491 | default: |
492 | return 0; |
493 | } |
494 | } |
495 | |
496 | static int sb_check_xattr_support(struct super_block *sb) |
497 | { |
498 | struct superblock_security_struct *sbsec = selinux_superblock(sb); |
499 | struct dentry *root = sb->s_root; |
500 | struct inode *root_inode = d_backing_inode(upper: root); |
501 | u32 sid; |
502 | int rc; |
503 | |
504 | /* |
505 | * Make sure that the xattr handler exists and that no |
506 | * error other than -ENODATA is returned by getxattr on |
507 | * the root directory. -ENODATA is ok, as this may be |
508 | * the first boot of the SELinux kernel before we have |
509 | * assigned xattr values to the filesystem. |
510 | */ |
511 | if (!(root_inode->i_opflags & IOP_XATTR)) { |
512 | pr_warn("SELinux: (dev %s, type %s) has no xattr support\n" , |
513 | sb->s_id, sb->s_type->name); |
514 | goto fallback; |
515 | } |
516 | |
517 | rc = __vfs_getxattr(root, root_inode, XATTR_NAME_SELINUX, NULL, 0); |
518 | if (rc < 0 && rc != -ENODATA) { |
519 | if (rc == -EOPNOTSUPP) { |
520 | pr_warn("SELinux: (dev %s, type %s) has no security xattr handler\n" , |
521 | sb->s_id, sb->s_type->name); |
522 | goto fallback; |
523 | } else { |
524 | pr_warn("SELinux: (dev %s, type %s) getxattr errno %d\n" , |
525 | sb->s_id, sb->s_type->name, -rc); |
526 | return rc; |
527 | } |
528 | } |
529 | return 0; |
530 | |
531 | fallback: |
532 | /* No xattr support - try to fallback to genfs if possible. */ |
533 | rc = security_genfs_sid(sb->s_type->name, "/" , |
534 | SECCLASS_DIR, &sid); |
535 | if (rc) |
536 | return -EOPNOTSUPP; |
537 | |
538 | pr_warn("SELinux: (dev %s, type %s) falling back to genfs\n" , |
539 | sb->s_id, sb->s_type->name); |
540 | sbsec->behavior = SECURITY_FS_USE_GENFS; |
541 | sbsec->sid = sid; |
542 | return 0; |
543 | } |
544 | |
545 | static int sb_finish_set_opts(struct super_block *sb) |
546 | { |
547 | struct superblock_security_struct *sbsec = selinux_superblock(sb); |
548 | struct dentry *root = sb->s_root; |
549 | struct inode *root_inode = d_backing_inode(upper: root); |
550 | int rc = 0; |
551 | |
552 | if (sbsec->behavior == SECURITY_FS_USE_XATTR) { |
553 | rc = sb_check_xattr_support(sb); |
554 | if (rc) |
555 | return rc; |
556 | } |
557 | |
558 | sbsec->flags |= SE_SBINITIALIZED; |
559 | |
560 | /* |
561 | * Explicitly set or clear SBLABEL_MNT. It's not sufficient to simply |
562 | * leave the flag untouched because sb_clone_mnt_opts might be handing |
563 | * us a superblock that needs the flag to be cleared. |
564 | */ |
565 | if (selinux_is_sblabel_mnt(sb)) |
566 | sbsec->flags |= SBLABEL_MNT; |
567 | else |
568 | sbsec->flags &= ~SBLABEL_MNT; |
569 | |
570 | /* Initialize the root inode. */ |
571 | rc = inode_doinit_with_dentry(inode: root_inode, opt_dentry: root); |
572 | |
573 | /* Initialize any other inodes associated with the superblock, e.g. |
574 | inodes created prior to initial policy load or inodes created |
575 | during get_sb by a pseudo filesystem that directly |
576 | populates itself. */ |
577 | spin_lock(lock: &sbsec->isec_lock); |
578 | while (!list_empty(head: &sbsec->isec_head)) { |
579 | struct inode_security_struct *isec = |
580 | list_first_entry(&sbsec->isec_head, |
581 | struct inode_security_struct, list); |
582 | struct inode *inode = isec->inode; |
583 | list_del_init(entry: &isec->list); |
584 | spin_unlock(lock: &sbsec->isec_lock); |
585 | inode = igrab(inode); |
586 | if (inode) { |
587 | if (!IS_PRIVATE(inode)) |
588 | inode_doinit_with_dentry(inode, NULL); |
589 | iput(inode); |
590 | } |
591 | spin_lock(lock: &sbsec->isec_lock); |
592 | } |
593 | spin_unlock(lock: &sbsec->isec_lock); |
594 | return rc; |
595 | } |
596 | |
597 | static int bad_option(struct superblock_security_struct *sbsec, char flag, |
598 | u32 old_sid, u32 new_sid) |
599 | { |
600 | char mnt_flags = sbsec->flags & SE_MNTMASK; |
601 | |
602 | /* check if the old mount command had the same options */ |
603 | if (sbsec->flags & SE_SBINITIALIZED) |
604 | if (!(sbsec->flags & flag) || |
605 | (old_sid != new_sid)) |
606 | return 1; |
607 | |
608 | /* check if we were passed the same options twice, |
609 | * aka someone passed context=a,context=b |
610 | */ |
611 | if (!(sbsec->flags & SE_SBINITIALIZED)) |
612 | if (mnt_flags & flag) |
613 | return 1; |
614 | return 0; |
615 | } |
616 | |
617 | /* |
618 | * Allow filesystems with binary mount data to explicitly set mount point |
619 | * labeling information. |
620 | */ |
621 | static int selinux_set_mnt_opts(struct super_block *sb, |
622 | void *mnt_opts, |
623 | unsigned long kern_flags, |
624 | unsigned long *set_kern_flags) |
625 | { |
626 | const struct cred *cred = current_cred(); |
627 | struct superblock_security_struct *sbsec = selinux_superblock(sb); |
628 | struct dentry *root = sb->s_root; |
629 | struct selinux_mnt_opts *opts = mnt_opts; |
630 | struct inode_security_struct *root_isec; |
631 | u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0; |
632 | u32 defcontext_sid = 0; |
633 | int rc = 0; |
634 | |
635 | /* |
636 | * Specifying internal flags without providing a place to |
637 | * place the results is not allowed |
638 | */ |
639 | if (kern_flags && !set_kern_flags) |
640 | return -EINVAL; |
641 | |
642 | mutex_lock(&sbsec->lock); |
643 | |
644 | if (!selinux_initialized()) { |
645 | if (!opts) { |
646 | /* Defer initialization until selinux_complete_init, |
647 | after the initial policy is loaded and the security |
648 | server is ready to handle calls. */ |
649 | if (kern_flags & SECURITY_LSM_NATIVE_LABELS) { |
650 | sbsec->flags |= SE_SBNATIVE; |
651 | *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; |
652 | } |
653 | goto out; |
654 | } |
655 | rc = -EINVAL; |
656 | pr_warn("SELinux: Unable to set superblock options " |
657 | "before the security server is initialized\n" ); |
658 | goto out; |
659 | } |
660 | |
661 | /* |
662 | * Binary mount data FS will come through this function twice. Once |
663 | * from an explicit call and once from the generic calls from the vfs. |
664 | * Since the generic VFS calls will not contain any security mount data |
665 | * we need to skip the double mount verification. |
666 | * |
667 | * This does open a hole in which we will not notice if the first |
668 | * mount using this sb set explicit options and a second mount using |
669 | * this sb does not set any security options. (The first options |
670 | * will be used for both mounts) |
671 | */ |
672 | if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) |
673 | && !opts) |
674 | goto out; |
675 | |
676 | root_isec = backing_inode_security_novalidate(dentry: root); |
677 | |
678 | /* |
679 | * parse the mount options, check if they are valid sids. |
680 | * also check if someone is trying to mount the same sb more |
681 | * than once with different security options. |
682 | */ |
683 | if (opts) { |
684 | if (opts->fscontext_sid) { |
685 | fscontext_sid = opts->fscontext_sid; |
686 | if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, |
687 | fscontext_sid)) |
688 | goto out_double_mount; |
689 | sbsec->flags |= FSCONTEXT_MNT; |
690 | } |
691 | if (opts->context_sid) { |
692 | context_sid = opts->context_sid; |
693 | if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, |
694 | context_sid)) |
695 | goto out_double_mount; |
696 | sbsec->flags |= CONTEXT_MNT; |
697 | } |
698 | if (opts->rootcontext_sid) { |
699 | rootcontext_sid = opts->rootcontext_sid; |
700 | if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, |
701 | rootcontext_sid)) |
702 | goto out_double_mount; |
703 | sbsec->flags |= ROOTCONTEXT_MNT; |
704 | } |
705 | if (opts->defcontext_sid) { |
706 | defcontext_sid = opts->defcontext_sid; |
707 | if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, |
708 | defcontext_sid)) |
709 | goto out_double_mount; |
710 | sbsec->flags |= DEFCONTEXT_MNT; |
711 | } |
712 | } |
713 | |
714 | if (sbsec->flags & SE_SBINITIALIZED) { |
715 | /* previously mounted with options, but not on this attempt? */ |
716 | if ((sbsec->flags & SE_MNTMASK) && !opts) |
717 | goto out_double_mount; |
718 | rc = 0; |
719 | goto out; |
720 | } |
721 | |
722 | if (strcmp(sb->s_type->name, "proc" ) == 0) |
723 | sbsec->flags |= SE_SBPROC | SE_SBGENFS; |
724 | |
725 | if (!strcmp(sb->s_type->name, "debugfs" ) || |
726 | !strcmp(sb->s_type->name, "tracefs" ) || |
727 | !strcmp(sb->s_type->name, "binder" ) || |
728 | !strcmp(sb->s_type->name, "bpf" ) || |
729 | !strcmp(sb->s_type->name, "pstore" ) || |
730 | !strcmp(sb->s_type->name, "securityfs" )) |
731 | sbsec->flags |= SE_SBGENFS; |
732 | |
733 | if (!strcmp(sb->s_type->name, "sysfs" ) || |
734 | !strcmp(sb->s_type->name, "cgroup" ) || |
735 | !strcmp(sb->s_type->name, "cgroup2" )) |
736 | sbsec->flags |= SE_SBGENFS | SE_SBGENFS_XATTR; |
737 | |
738 | if (!sbsec->behavior) { |
739 | /* |
740 | * Determine the labeling behavior to use for this |
741 | * filesystem type. |
742 | */ |
743 | rc = security_fs_use(sb); |
744 | if (rc) { |
745 | pr_warn("%s: security_fs_use(%s) returned %d\n" , |
746 | __func__, sb->s_type->name, rc); |
747 | goto out; |
748 | } |
749 | } |
750 | |
751 | /* |
752 | * If this is a user namespace mount and the filesystem type is not |
753 | * explicitly whitelisted, then no contexts are allowed on the command |
754 | * line and security labels must be ignored. |
755 | */ |
756 | if (sb->s_user_ns != &init_user_ns && |
757 | strcmp(sb->s_type->name, "tmpfs" ) && |
758 | strcmp(sb->s_type->name, "ramfs" ) && |
759 | strcmp(sb->s_type->name, "devpts" ) && |
760 | strcmp(sb->s_type->name, "overlay" )) { |
761 | if (context_sid || fscontext_sid || rootcontext_sid || |
762 | defcontext_sid) { |
763 | rc = -EACCES; |
764 | goto out; |
765 | } |
766 | if (sbsec->behavior == SECURITY_FS_USE_XATTR) { |
767 | sbsec->behavior = SECURITY_FS_USE_MNTPOINT; |
768 | rc = security_transition_sid(current_sid(), |
769 | current_sid(), |
770 | SECCLASS_FILE, NULL, |
771 | &sbsec->mntpoint_sid); |
772 | if (rc) |
773 | goto out; |
774 | } |
775 | goto out_set_opts; |
776 | } |
777 | |
778 | /* sets the context of the superblock for the fs being mounted. */ |
779 | if (fscontext_sid) { |
780 | rc = may_context_mount_sb_relabel(sid: fscontext_sid, sbsec, cred); |
781 | if (rc) |
782 | goto out; |
783 | |
784 | sbsec->sid = fscontext_sid; |
785 | } |
786 | |
787 | /* |
788 | * Switch to using mount point labeling behavior. |
789 | * sets the label used on all file below the mountpoint, and will set |
790 | * the superblock context if not already set. |
791 | */ |
792 | if (sbsec->flags & SE_SBNATIVE) { |
793 | /* |
794 | * This means we are initializing a superblock that has been |
795 | * mounted before the SELinux was initialized and the |
796 | * filesystem requested native labeling. We had already |
797 | * returned SECURITY_LSM_NATIVE_LABELS in *set_kern_flags |
798 | * in the original mount attempt, so now we just need to set |
799 | * the SECURITY_FS_USE_NATIVE behavior. |
800 | */ |
801 | sbsec->behavior = SECURITY_FS_USE_NATIVE; |
802 | } else if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) { |
803 | sbsec->behavior = SECURITY_FS_USE_NATIVE; |
804 | *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; |
805 | } |
806 | |
807 | if (context_sid) { |
808 | if (!fscontext_sid) { |
809 | rc = may_context_mount_sb_relabel(sid: context_sid, sbsec, |
810 | cred); |
811 | if (rc) |
812 | goto out; |
813 | sbsec->sid = context_sid; |
814 | } else { |
815 | rc = may_context_mount_inode_relabel(sid: context_sid, sbsec, |
816 | cred); |
817 | if (rc) |
818 | goto out; |
819 | } |
820 | if (!rootcontext_sid) |
821 | rootcontext_sid = context_sid; |
822 | |
823 | sbsec->mntpoint_sid = context_sid; |
824 | sbsec->behavior = SECURITY_FS_USE_MNTPOINT; |
825 | } |
826 | |
827 | if (rootcontext_sid) { |
828 | rc = may_context_mount_inode_relabel(sid: rootcontext_sid, sbsec, |
829 | cred); |
830 | if (rc) |
831 | goto out; |
832 | |
833 | root_isec->sid = rootcontext_sid; |
834 | root_isec->initialized = LABEL_INITIALIZED; |
835 | } |
836 | |
837 | if (defcontext_sid) { |
838 | if (sbsec->behavior != SECURITY_FS_USE_XATTR && |
839 | sbsec->behavior != SECURITY_FS_USE_NATIVE) { |
840 | rc = -EINVAL; |
841 | pr_warn("SELinux: defcontext option is " |
842 | "invalid for this filesystem type\n" ); |
843 | goto out; |
844 | } |
845 | |
846 | if (defcontext_sid != sbsec->def_sid) { |
847 | rc = may_context_mount_inode_relabel(sid: defcontext_sid, |
848 | sbsec, cred); |
849 | if (rc) |
850 | goto out; |
851 | } |
852 | |
853 | sbsec->def_sid = defcontext_sid; |
854 | } |
855 | |
856 | out_set_opts: |
857 | rc = sb_finish_set_opts(sb); |
858 | out: |
859 | mutex_unlock(lock: &sbsec->lock); |
860 | return rc; |
861 | out_double_mount: |
862 | rc = -EINVAL; |
863 | pr_warn("SELinux: mount invalid. Same superblock, different " |
864 | "security settings for (dev %s, type %s)\n" , sb->s_id, |
865 | sb->s_type->name); |
866 | goto out; |
867 | } |
868 | |
869 | static int selinux_cmp_sb_context(const struct super_block *oldsb, |
870 | const struct super_block *newsb) |
871 | { |
872 | struct superblock_security_struct *old = selinux_superblock(oldsb); |
873 | struct superblock_security_struct *new = selinux_superblock(newsb); |
874 | char oldflags = old->flags & SE_MNTMASK; |
875 | char newflags = new->flags & SE_MNTMASK; |
876 | |
877 | if (oldflags != newflags) |
878 | goto mismatch; |
879 | if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid) |
880 | goto mismatch; |
881 | if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid) |
882 | goto mismatch; |
883 | if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid) |
884 | goto mismatch; |
885 | if (oldflags & ROOTCONTEXT_MNT) { |
886 | struct inode_security_struct *oldroot = backing_inode_security(dentry: oldsb->s_root); |
887 | struct inode_security_struct *newroot = backing_inode_security(dentry: newsb->s_root); |
888 | if (oldroot->sid != newroot->sid) |
889 | goto mismatch; |
890 | } |
891 | return 0; |
892 | mismatch: |
893 | pr_warn("SELinux: mount invalid. Same superblock, " |
894 | "different security settings for (dev %s, " |
895 | "type %s)\n" , newsb->s_id, newsb->s_type->name); |
896 | return -EBUSY; |
897 | } |
898 | |
899 | static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb, |
900 | struct super_block *newsb, |
901 | unsigned long kern_flags, |
902 | unsigned long *set_kern_flags) |
903 | { |
904 | int rc = 0; |
905 | const struct superblock_security_struct *oldsbsec = |
906 | selinux_superblock(oldsb); |
907 | struct superblock_security_struct *newsbsec = selinux_superblock(newsb); |
908 | |
909 | int set_fscontext = (oldsbsec->flags & FSCONTEXT_MNT); |
910 | int set_context = (oldsbsec->flags & CONTEXT_MNT); |
911 | int set_rootcontext = (oldsbsec->flags & ROOTCONTEXT_MNT); |
912 | |
913 | /* |
914 | * Specifying internal flags without providing a place to |
915 | * place the results is not allowed. |
916 | */ |
917 | if (kern_flags && !set_kern_flags) |
918 | return -EINVAL; |
919 | |
920 | mutex_lock(&newsbsec->lock); |
921 | |
922 | /* |
923 | * if the parent was able to be mounted it clearly had no special lsm |
924 | * mount options. thus we can safely deal with this superblock later |
925 | */ |
926 | if (!selinux_initialized()) { |
927 | if (kern_flags & SECURITY_LSM_NATIVE_LABELS) { |
928 | newsbsec->flags |= SE_SBNATIVE; |
929 | *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; |
930 | } |
931 | goto out; |
932 | } |
933 | |
934 | /* how can we clone if the old one wasn't set up?? */ |
935 | BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED)); |
936 | |
937 | /* if fs is reusing a sb, make sure that the contexts match */ |
938 | if (newsbsec->flags & SE_SBINITIALIZED) { |
939 | mutex_unlock(lock: &newsbsec->lock); |
940 | if ((kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context) |
941 | *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; |
942 | return selinux_cmp_sb_context(oldsb, newsb); |
943 | } |
944 | |
945 | newsbsec->flags = oldsbsec->flags; |
946 | |
947 | newsbsec->sid = oldsbsec->sid; |
948 | newsbsec->def_sid = oldsbsec->def_sid; |
949 | newsbsec->behavior = oldsbsec->behavior; |
950 | |
951 | if (newsbsec->behavior == SECURITY_FS_USE_NATIVE && |
952 | !(kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context) { |
953 | rc = security_fs_use(newsb); |
954 | if (rc) |
955 | goto out; |
956 | } |
957 | |
958 | if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !set_context) { |
959 | newsbsec->behavior = SECURITY_FS_USE_NATIVE; |
960 | *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; |
961 | } |
962 | |
963 | if (set_context) { |
964 | u32 sid = oldsbsec->mntpoint_sid; |
965 | |
966 | if (!set_fscontext) |
967 | newsbsec->sid = sid; |
968 | if (!set_rootcontext) { |
969 | struct inode_security_struct *newisec = backing_inode_security(dentry: newsb->s_root); |
970 | newisec->sid = sid; |
971 | } |
972 | newsbsec->mntpoint_sid = sid; |
973 | } |
974 | if (set_rootcontext) { |
975 | const struct inode_security_struct *oldisec = backing_inode_security(dentry: oldsb->s_root); |
976 | struct inode_security_struct *newisec = backing_inode_security(dentry: newsb->s_root); |
977 | |
978 | newisec->sid = oldisec->sid; |
979 | } |
980 | |
981 | sb_finish_set_opts(sb: newsb); |
982 | out: |
983 | mutex_unlock(lock: &newsbsec->lock); |
984 | return rc; |
985 | } |
986 | |
987 | /* |
988 | * NOTE: the caller is responsible for freeing the memory even if on error. |
989 | */ |
990 | static int selinux_add_opt(int token, const char *s, void **mnt_opts) |
991 | { |
992 | struct selinux_mnt_opts *opts = *mnt_opts; |
993 | u32 *dst_sid; |
994 | int rc; |
995 | |
996 | if (token == Opt_seclabel) |
997 | /* eaten and completely ignored */ |
998 | return 0; |
999 | if (!s) |
1000 | return -EINVAL; |
1001 | |
1002 | if (!selinux_initialized()) { |
1003 | pr_warn("SELinux: Unable to set superblock options before the security server is initialized\n" ); |
1004 | return -EINVAL; |
1005 | } |
1006 | |
1007 | if (!opts) { |
1008 | opts = kzalloc(size: sizeof(*opts), GFP_KERNEL); |
1009 | if (!opts) |
1010 | return -ENOMEM; |
1011 | *mnt_opts = opts; |
1012 | } |
1013 | |
1014 | switch (token) { |
1015 | case Opt_context: |
1016 | if (opts->context_sid || opts->defcontext_sid) |
1017 | goto err; |
1018 | dst_sid = &opts->context_sid; |
1019 | break; |
1020 | case Opt_fscontext: |
1021 | if (opts->fscontext_sid) |
1022 | goto err; |
1023 | dst_sid = &opts->fscontext_sid; |
1024 | break; |
1025 | case Opt_rootcontext: |
1026 | if (opts->rootcontext_sid) |
1027 | goto err; |
1028 | dst_sid = &opts->rootcontext_sid; |
1029 | break; |
1030 | case Opt_defcontext: |
1031 | if (opts->context_sid || opts->defcontext_sid) |
1032 | goto err; |
1033 | dst_sid = &opts->defcontext_sid; |
1034 | break; |
1035 | default: |
1036 | WARN_ON(1); |
1037 | return -EINVAL; |
1038 | } |
1039 | rc = security_context_str_to_sid(s, dst_sid, GFP_KERNEL); |
1040 | if (rc) |
1041 | pr_warn("SELinux: security_context_str_to_sid (%s) failed with errno=%d\n" , |
1042 | s, rc); |
1043 | return rc; |
1044 | |
1045 | err: |
1046 | pr_warn(SEL_MOUNT_FAIL_MSG); |
1047 | return -EINVAL; |
1048 | } |
1049 | |
1050 | static int show_sid(struct seq_file *m, u32 sid) |
1051 | { |
1052 | char *context = NULL; |
1053 | u32 len; |
1054 | int rc; |
1055 | |
1056 | rc = security_sid_to_context(sid, &context, &len); |
1057 | if (!rc) { |
1058 | bool has_comma = strchr(context, ','); |
1059 | |
1060 | seq_putc(m, c: '='); |
1061 | if (has_comma) |
1062 | seq_putc(m, c: '\"'); |
1063 | seq_escape(m, s: context, esc: "\"\n\\" ); |
1064 | if (has_comma) |
1065 | seq_putc(m, c: '\"'); |
1066 | } |
1067 | kfree(objp: context); |
1068 | return rc; |
1069 | } |
1070 | |
1071 | static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb) |
1072 | { |
1073 | struct superblock_security_struct *sbsec = selinux_superblock(sb); |
1074 | int rc; |
1075 | |
1076 | if (!(sbsec->flags & SE_SBINITIALIZED)) |
1077 | return 0; |
1078 | |
1079 | if (!selinux_initialized()) |
1080 | return 0; |
1081 | |
1082 | if (sbsec->flags & FSCONTEXT_MNT) { |
1083 | seq_putc(m, c: ','); |
1084 | seq_puts(m, FSCONTEXT_STR); |
1085 | rc = show_sid(m, sid: sbsec->sid); |
1086 | if (rc) |
1087 | return rc; |
1088 | } |
1089 | if (sbsec->flags & CONTEXT_MNT) { |
1090 | seq_putc(m, c: ','); |
1091 | seq_puts(m, CONTEXT_STR); |
1092 | rc = show_sid(m, sid: sbsec->mntpoint_sid); |
1093 | if (rc) |
1094 | return rc; |
1095 | } |
1096 | if (sbsec->flags & DEFCONTEXT_MNT) { |
1097 | seq_putc(m, c: ','); |
1098 | seq_puts(m, DEFCONTEXT_STR); |
1099 | rc = show_sid(m, sid: sbsec->def_sid); |
1100 | if (rc) |
1101 | return rc; |
1102 | } |
1103 | if (sbsec->flags & ROOTCONTEXT_MNT) { |
1104 | struct dentry *root = sb->s_root; |
1105 | struct inode_security_struct *isec = backing_inode_security(dentry: root); |
1106 | seq_putc(m, c: ','); |
1107 | seq_puts(m, ROOTCONTEXT_STR); |
1108 | rc = show_sid(m, sid: isec->sid); |
1109 | if (rc) |
1110 | return rc; |
1111 | } |
1112 | if (sbsec->flags & SBLABEL_MNT) { |
1113 | seq_putc(m, c: ','); |
1114 | seq_puts(m, SECLABEL_STR); |
1115 | } |
1116 | return 0; |
1117 | } |
1118 | |
1119 | static inline u16 inode_mode_to_security_class(umode_t mode) |
1120 | { |
1121 | switch (mode & S_IFMT) { |
1122 | case S_IFSOCK: |
1123 | return SECCLASS_SOCK_FILE; |
1124 | case S_IFLNK: |
1125 | return SECCLASS_LNK_FILE; |
1126 | case S_IFREG: |
1127 | return SECCLASS_FILE; |
1128 | case S_IFBLK: |
1129 | return SECCLASS_BLK_FILE; |
1130 | case S_IFDIR: |
1131 | return SECCLASS_DIR; |
1132 | case S_IFCHR: |
1133 | return SECCLASS_CHR_FILE; |
1134 | case S_IFIFO: |
1135 | return SECCLASS_FIFO_FILE; |
1136 | |
1137 | } |
1138 | |
1139 | return SECCLASS_FILE; |
1140 | } |
1141 | |
1142 | static inline int default_protocol_stream(int protocol) |
1143 | { |
1144 | return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP || |
1145 | protocol == IPPROTO_MPTCP); |
1146 | } |
1147 | |
1148 | static inline int default_protocol_dgram(int protocol) |
1149 | { |
1150 | return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP); |
1151 | } |
1152 | |
1153 | static inline u16 socket_type_to_security_class(int family, int type, int protocol) |
1154 | { |
1155 | bool extsockclass = selinux_policycap_extsockclass(); |
1156 | |
1157 | switch (family) { |
1158 | case PF_UNIX: |
1159 | switch (type) { |
1160 | case SOCK_STREAM: |
1161 | case SOCK_SEQPACKET: |
1162 | return SECCLASS_UNIX_STREAM_SOCKET; |
1163 | case SOCK_DGRAM: |
1164 | case SOCK_RAW: |
1165 | return SECCLASS_UNIX_DGRAM_SOCKET; |
1166 | } |
1167 | break; |
1168 | case PF_INET: |
1169 | case PF_INET6: |
1170 | switch (type) { |
1171 | case SOCK_STREAM: |
1172 | case SOCK_SEQPACKET: |
1173 | if (default_protocol_stream(protocol)) |
1174 | return SECCLASS_TCP_SOCKET; |
1175 | else if (extsockclass && protocol == IPPROTO_SCTP) |
1176 | return SECCLASS_SCTP_SOCKET; |
1177 | else |
1178 | return SECCLASS_RAWIP_SOCKET; |
1179 | case SOCK_DGRAM: |
1180 | if (default_protocol_dgram(protocol)) |
1181 | return SECCLASS_UDP_SOCKET; |
1182 | else if (extsockclass && (protocol == IPPROTO_ICMP || |
1183 | protocol == IPPROTO_ICMPV6)) |
1184 | return SECCLASS_ICMP_SOCKET; |
1185 | else |
1186 | return SECCLASS_RAWIP_SOCKET; |
1187 | case SOCK_DCCP: |
1188 | return SECCLASS_DCCP_SOCKET; |
1189 | default: |
1190 | return SECCLASS_RAWIP_SOCKET; |
1191 | } |
1192 | break; |
1193 | case PF_NETLINK: |
1194 | switch (protocol) { |
1195 | case NETLINK_ROUTE: |
1196 | return SECCLASS_NETLINK_ROUTE_SOCKET; |
1197 | case NETLINK_SOCK_DIAG: |
1198 | return SECCLASS_NETLINK_TCPDIAG_SOCKET; |
1199 | case NETLINK_NFLOG: |
1200 | return SECCLASS_NETLINK_NFLOG_SOCKET; |
1201 | case NETLINK_XFRM: |
1202 | return SECCLASS_NETLINK_XFRM_SOCKET; |
1203 | case NETLINK_SELINUX: |
1204 | return SECCLASS_NETLINK_SELINUX_SOCKET; |
1205 | case NETLINK_ISCSI: |
1206 | return SECCLASS_NETLINK_ISCSI_SOCKET; |
1207 | case NETLINK_AUDIT: |
1208 | return SECCLASS_NETLINK_AUDIT_SOCKET; |
1209 | case NETLINK_FIB_LOOKUP: |
1210 | return SECCLASS_NETLINK_FIB_LOOKUP_SOCKET; |
1211 | case NETLINK_CONNECTOR: |
1212 | return SECCLASS_NETLINK_CONNECTOR_SOCKET; |
1213 | case NETLINK_NETFILTER: |
1214 | return SECCLASS_NETLINK_NETFILTER_SOCKET; |
1215 | case NETLINK_DNRTMSG: |
1216 | return SECCLASS_NETLINK_DNRT_SOCKET; |
1217 | case NETLINK_KOBJECT_UEVENT: |
1218 | return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET; |
1219 | case NETLINK_GENERIC: |
1220 | return SECCLASS_NETLINK_GENERIC_SOCKET; |
1221 | case NETLINK_SCSITRANSPORT: |
1222 | return SECCLASS_NETLINK_SCSITRANSPORT_SOCKET; |
1223 | case NETLINK_RDMA: |
1224 | return SECCLASS_NETLINK_RDMA_SOCKET; |
1225 | case NETLINK_CRYPTO: |
1226 | return SECCLASS_NETLINK_CRYPTO_SOCKET; |
1227 | default: |
1228 | return SECCLASS_NETLINK_SOCKET; |
1229 | } |
1230 | case PF_PACKET: |
1231 | return SECCLASS_PACKET_SOCKET; |
1232 | case PF_KEY: |
1233 | return SECCLASS_KEY_SOCKET; |
1234 | case PF_APPLETALK: |
1235 | return SECCLASS_APPLETALK_SOCKET; |
1236 | } |
1237 | |
1238 | if (extsockclass) { |
1239 | switch (family) { |
1240 | case PF_AX25: |
1241 | return SECCLASS_AX25_SOCKET; |
1242 | case PF_IPX: |
1243 | return SECCLASS_IPX_SOCKET; |
1244 | case PF_NETROM: |
1245 | return SECCLASS_NETROM_SOCKET; |
1246 | case PF_ATMPVC: |
1247 | return SECCLASS_ATMPVC_SOCKET; |
1248 | case PF_X25: |
1249 | return SECCLASS_X25_SOCKET; |
1250 | case PF_ROSE: |
1251 | return SECCLASS_ROSE_SOCKET; |
1252 | case PF_DECnet: |
1253 | return SECCLASS_DECNET_SOCKET; |
1254 | case PF_ATMSVC: |
1255 | return SECCLASS_ATMSVC_SOCKET; |
1256 | case PF_RDS: |
1257 | return SECCLASS_RDS_SOCKET; |
1258 | case PF_IRDA: |
1259 | return SECCLASS_IRDA_SOCKET; |
1260 | case PF_PPPOX: |
1261 | return SECCLASS_PPPOX_SOCKET; |
1262 | case PF_LLC: |
1263 | return SECCLASS_LLC_SOCKET; |
1264 | case PF_CAN: |
1265 | return SECCLASS_CAN_SOCKET; |
1266 | case PF_TIPC: |
1267 | return SECCLASS_TIPC_SOCKET; |
1268 | case PF_BLUETOOTH: |
1269 | return SECCLASS_BLUETOOTH_SOCKET; |
1270 | case PF_IUCV: |
1271 | return SECCLASS_IUCV_SOCKET; |
1272 | case PF_RXRPC: |
1273 | return SECCLASS_RXRPC_SOCKET; |
1274 | case PF_ISDN: |
1275 | return SECCLASS_ISDN_SOCKET; |
1276 | case PF_PHONET: |
1277 | return SECCLASS_PHONET_SOCKET; |
1278 | case PF_IEEE802154: |
1279 | return SECCLASS_IEEE802154_SOCKET; |
1280 | case PF_CAIF: |
1281 | return SECCLASS_CAIF_SOCKET; |
1282 | case PF_ALG: |
1283 | return SECCLASS_ALG_SOCKET; |
1284 | case PF_NFC: |
1285 | return SECCLASS_NFC_SOCKET; |
1286 | case PF_VSOCK: |
1287 | return SECCLASS_VSOCK_SOCKET; |
1288 | case PF_KCM: |
1289 | return SECCLASS_KCM_SOCKET; |
1290 | case PF_QIPCRTR: |
1291 | return SECCLASS_QIPCRTR_SOCKET; |
1292 | case PF_SMC: |
1293 | return SECCLASS_SMC_SOCKET; |
1294 | case PF_XDP: |
1295 | return SECCLASS_XDP_SOCKET; |
1296 | case PF_MCTP: |
1297 | return SECCLASS_MCTP_SOCKET; |
1298 | #if PF_MAX > 46 |
1299 | #error New address family defined, please update this function. |
1300 | #endif |
1301 | } |
1302 | } |
1303 | |
1304 | return SECCLASS_SOCKET; |
1305 | } |
1306 | |
1307 | static int selinux_genfs_get_sid(struct dentry *dentry, |
1308 | u16 tclass, |
1309 | u16 flags, |
1310 | u32 *sid) |
1311 | { |
1312 | int rc; |
1313 | struct super_block *sb = dentry->d_sb; |
1314 | char *buffer, *path; |
1315 | |
1316 | buffer = (char *)__get_free_page(GFP_KERNEL); |
1317 | if (!buffer) |
1318 | return -ENOMEM; |
1319 | |
1320 | path = dentry_path_raw(dentry, buffer, PAGE_SIZE); |
1321 | if (IS_ERR(ptr: path)) |
1322 | rc = PTR_ERR(ptr: path); |
1323 | else { |
1324 | if (flags & SE_SBPROC) { |
1325 | /* each process gets a /proc/PID/ entry. Strip off the |
1326 | * PID part to get a valid selinux labeling. |
1327 | * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */ |
1328 | while (path[1] >= '0' && path[1] <= '9') { |
1329 | path[1] = '/'; |
1330 | path++; |
1331 | } |
1332 | } |
1333 | rc = security_genfs_sid(sb->s_type->name, |
1334 | path, tclass, sid); |
1335 | if (rc == -ENOENT) { |
1336 | /* No match in policy, mark as unlabeled. */ |
1337 | *sid = SECINITSID_UNLABELED; |
1338 | rc = 0; |
1339 | } |
1340 | } |
1341 | free_page((unsigned long)buffer); |
1342 | return rc; |
1343 | } |
1344 | |
1345 | static int inode_doinit_use_xattr(struct inode *inode, struct dentry *dentry, |
1346 | u32 def_sid, u32 *sid) |
1347 | { |
1348 | #define INITCONTEXTLEN 255 |
1349 | char *context; |
1350 | unsigned int len; |
1351 | int rc; |
1352 | |
1353 | len = INITCONTEXTLEN; |
1354 | context = kmalloc(size: len + 1, GFP_NOFS); |
1355 | if (!context) |
1356 | return -ENOMEM; |
1357 | |
1358 | context[len] = '\0'; |
1359 | rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len); |
1360 | if (rc == -ERANGE) { |
1361 | kfree(objp: context); |
1362 | |
1363 | /* Need a larger buffer. Query for the right size. */ |
1364 | rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, NULL, 0); |
1365 | if (rc < 0) |
1366 | return rc; |
1367 | |
1368 | len = rc; |
1369 | context = kmalloc(size: len + 1, GFP_NOFS); |
1370 | if (!context) |
1371 | return -ENOMEM; |
1372 | |
1373 | context[len] = '\0'; |
1374 | rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, |
1375 | context, len); |
1376 | } |
1377 | if (rc < 0) { |
1378 | kfree(objp: context); |
1379 | if (rc != -ENODATA) { |
1380 | pr_warn("SELinux: %s: getxattr returned %d for dev=%s ino=%ld\n" , |
1381 | __func__, -rc, inode->i_sb->s_id, inode->i_ino); |
1382 | return rc; |
1383 | } |
1384 | *sid = def_sid; |
1385 | return 0; |
1386 | } |
1387 | |
1388 | rc = security_context_to_sid_default(context, rc, sid, |
1389 | def_sid, GFP_NOFS); |
1390 | if (rc) { |
1391 | char *dev = inode->i_sb->s_id; |
1392 | unsigned long ino = inode->i_ino; |
1393 | |
1394 | if (rc == -EINVAL) { |
1395 | pr_notice_ratelimited("SELinux: inode=%lu on dev=%s was found to have an invalid context=%s. This indicates you may need to relabel the inode or the filesystem in question.\n" , |
1396 | ino, dev, context); |
1397 | } else { |
1398 | pr_warn("SELinux: %s: context_to_sid(%s) returned %d for dev=%s ino=%ld\n" , |
1399 | __func__, context, -rc, dev, ino); |
1400 | } |
1401 | } |
1402 | kfree(objp: context); |
1403 | return 0; |
1404 | } |
1405 | |
1406 | /* The inode's security attributes must be initialized before first use. */ |
1407 | static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry) |
1408 | { |
1409 | struct superblock_security_struct *sbsec = NULL; |
1410 | struct inode_security_struct *isec = selinux_inode(inode); |
1411 | u32 task_sid, sid = 0; |
1412 | u16 sclass; |
1413 | struct dentry *dentry; |
1414 | int rc = 0; |
1415 | |
1416 | if (isec->initialized == LABEL_INITIALIZED) |
1417 | return 0; |
1418 | |
1419 | spin_lock(lock: &isec->lock); |
1420 | if (isec->initialized == LABEL_INITIALIZED) |
1421 | goto out_unlock; |
1422 | |
1423 | if (isec->sclass == SECCLASS_FILE) |
1424 | isec->sclass = inode_mode_to_security_class(mode: inode->i_mode); |
1425 | |
1426 | sbsec = selinux_superblock(inode->i_sb); |
1427 | if (!(sbsec->flags & SE_SBINITIALIZED)) { |
1428 | /* Defer initialization until selinux_complete_init, |
1429 | after the initial policy is loaded and the security |
1430 | server is ready to handle calls. */ |
1431 | spin_lock(lock: &sbsec->isec_lock); |
1432 | if (list_empty(head: &isec->list)) |
1433 | list_add(new: &isec->list, head: &sbsec->isec_head); |
1434 | spin_unlock(lock: &sbsec->isec_lock); |
1435 | goto out_unlock; |
1436 | } |
1437 | |
1438 | sclass = isec->sclass; |
1439 | task_sid = isec->task_sid; |
1440 | sid = isec->sid; |
1441 | isec->initialized = LABEL_PENDING; |
1442 | spin_unlock(lock: &isec->lock); |
1443 | |
1444 | switch (sbsec->behavior) { |
1445 | /* |
1446 | * In case of SECURITY_FS_USE_NATIVE we need to re-fetch the labels |
1447 | * via xattr when called from delayed_superblock_init(). |
1448 | */ |
1449 | case SECURITY_FS_USE_NATIVE: |
1450 | case SECURITY_FS_USE_XATTR: |
1451 | if (!(inode->i_opflags & IOP_XATTR)) { |
1452 | sid = sbsec->def_sid; |
1453 | break; |
1454 | } |
1455 | /* Need a dentry, since the xattr API requires one. |
1456 | Life would be simpler if we could just pass the inode. */ |
1457 | if (opt_dentry) { |
1458 | /* Called from d_instantiate or d_splice_alias. */ |
1459 | dentry = dget(dentry: opt_dentry); |
1460 | } else { |
1461 | /* |
1462 | * Called from selinux_complete_init, try to find a dentry. |
1463 | * Some filesystems really want a connected one, so try |
1464 | * that first. We could split SECURITY_FS_USE_XATTR in |
1465 | * two, depending upon that... |
1466 | */ |
1467 | dentry = d_find_alias(inode); |
1468 | if (!dentry) |
1469 | dentry = d_find_any_alias(inode); |
1470 | } |
1471 | if (!dentry) { |
1472 | /* |
1473 | * this is can be hit on boot when a file is accessed |
1474 | * before the policy is loaded. When we load policy we |
1475 | * may find inodes that have no dentry on the |
1476 | * sbsec->isec_head list. No reason to complain as these |
1477 | * will get fixed up the next time we go through |
1478 | * inode_doinit with a dentry, before these inodes could |
1479 | * be used again by userspace. |
1480 | */ |
1481 | goto out_invalid; |
1482 | } |
1483 | |
1484 | rc = inode_doinit_use_xattr(inode, dentry, def_sid: sbsec->def_sid, |
1485 | sid: &sid); |
1486 | dput(dentry); |
1487 | if (rc) |
1488 | goto out; |
1489 | break; |
1490 | case SECURITY_FS_USE_TASK: |
1491 | sid = task_sid; |
1492 | break; |
1493 | case SECURITY_FS_USE_TRANS: |
1494 | /* Default to the fs SID. */ |
1495 | sid = sbsec->sid; |
1496 | |
1497 | /* Try to obtain a transition SID. */ |
1498 | rc = security_transition_sid(task_sid, sid, |
1499 | sclass, NULL, &sid); |
1500 | if (rc) |
1501 | goto out; |
1502 | break; |
1503 | case SECURITY_FS_USE_MNTPOINT: |
1504 | sid = sbsec->mntpoint_sid; |
1505 | break; |
1506 | default: |
1507 | /* Default to the fs superblock SID. */ |
1508 | sid = sbsec->sid; |
1509 | |
1510 | if ((sbsec->flags & SE_SBGENFS) && |
1511 | (!S_ISLNK(inode->i_mode) || |
1512 | selinux_policycap_genfs_seclabel_symlinks())) { |
1513 | /* We must have a dentry to determine the label on |
1514 | * procfs inodes */ |
1515 | if (opt_dentry) { |
1516 | /* Called from d_instantiate or |
1517 | * d_splice_alias. */ |
1518 | dentry = dget(dentry: opt_dentry); |
1519 | } else { |
1520 | /* Called from selinux_complete_init, try to |
1521 | * find a dentry. Some filesystems really want |
1522 | * a connected one, so try that first. |
1523 | */ |
1524 | dentry = d_find_alias(inode); |
1525 | if (!dentry) |
1526 | dentry = d_find_any_alias(inode); |
1527 | } |
1528 | /* |
1529 | * This can be hit on boot when a file is accessed |
1530 | * before the policy is loaded. When we load policy we |
1531 | * may find inodes that have no dentry on the |
1532 | * sbsec->isec_head list. No reason to complain as |
1533 | * these will get fixed up the next time we go through |
1534 | * inode_doinit() with a dentry, before these inodes |
1535 | * could be used again by userspace. |
1536 | */ |
1537 | if (!dentry) |
1538 | goto out_invalid; |
1539 | rc = selinux_genfs_get_sid(dentry, tclass: sclass, |
1540 | flags: sbsec->flags, sid: &sid); |
1541 | if (rc) { |
1542 | dput(dentry); |
1543 | goto out; |
1544 | } |
1545 | |
1546 | if ((sbsec->flags & SE_SBGENFS_XATTR) && |
1547 | (inode->i_opflags & IOP_XATTR)) { |
1548 | rc = inode_doinit_use_xattr(inode, dentry, |
1549 | def_sid: sid, sid: &sid); |
1550 | if (rc) { |
1551 | dput(dentry); |
1552 | goto out; |
1553 | } |
1554 | } |
1555 | dput(dentry); |
1556 | } |
1557 | break; |
1558 | } |
1559 | |
1560 | out: |
1561 | spin_lock(lock: &isec->lock); |
1562 | if (isec->initialized == LABEL_PENDING) { |
1563 | if (rc) { |
1564 | isec->initialized = LABEL_INVALID; |
1565 | goto out_unlock; |
1566 | } |
1567 | isec->initialized = LABEL_INITIALIZED; |
1568 | isec->sid = sid; |
1569 | } |
1570 | |
1571 | out_unlock: |
1572 | spin_unlock(lock: &isec->lock); |
1573 | return rc; |
1574 | |
1575 | out_invalid: |
1576 | spin_lock(lock: &isec->lock); |
1577 | if (isec->initialized == LABEL_PENDING) { |
1578 | isec->initialized = LABEL_INVALID; |
1579 | isec->sid = sid; |
1580 | } |
1581 | spin_unlock(lock: &isec->lock); |
1582 | return 0; |
1583 | } |
1584 | |
1585 | /* Convert a Linux signal to an access vector. */ |
1586 | static inline u32 signal_to_av(int sig) |
1587 | { |
1588 | u32 perm = 0; |
1589 | |
1590 | switch (sig) { |
1591 | case SIGCHLD: |
1592 | /* Commonly granted from child to parent. */ |
1593 | perm = PROCESS__SIGCHLD; |
1594 | break; |
1595 | case SIGKILL: |
1596 | /* Cannot be caught or ignored */ |
1597 | perm = PROCESS__SIGKILL; |
1598 | break; |
1599 | case SIGSTOP: |
1600 | /* Cannot be caught or ignored */ |
1601 | perm = PROCESS__SIGSTOP; |
1602 | break; |
1603 | default: |
1604 | /* All other signals. */ |
1605 | perm = PROCESS__SIGNAL; |
1606 | break; |
1607 | } |
1608 | |
1609 | return perm; |
1610 | } |
1611 | |
1612 | #if CAP_LAST_CAP > 63 |
1613 | #error Fix SELinux to handle capabilities > 63. |
1614 | #endif |
1615 | |
1616 | /* Check whether a task is allowed to use a capability. */ |
1617 | static int cred_has_capability(const struct cred *cred, |
1618 | int cap, unsigned int opts, bool initns) |
1619 | { |
1620 | struct common_audit_data ad; |
1621 | struct av_decision avd; |
1622 | u16 sclass; |
1623 | u32 sid = cred_sid(cred); |
1624 | u32 av = CAP_TO_MASK(cap); |
1625 | int rc; |
1626 | |
1627 | ad.type = LSM_AUDIT_DATA_CAP; |
1628 | ad.u.cap = cap; |
1629 | |
1630 | switch (CAP_TO_INDEX(cap)) { |
1631 | case 0: |
1632 | sclass = initns ? SECCLASS_CAPABILITY : SECCLASS_CAP_USERNS; |
1633 | break; |
1634 | case 1: |
1635 | sclass = initns ? SECCLASS_CAPABILITY2 : SECCLASS_CAP2_USERNS; |
1636 | break; |
1637 | default: |
1638 | pr_err("SELinux: out of range capability %d\n" , cap); |
1639 | BUG(); |
1640 | return -EINVAL; |
1641 | } |
1642 | |
1643 | rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd); |
1644 | if (!(opts & CAP_OPT_NOAUDIT)) { |
1645 | int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad); |
1646 | if (rc2) |
1647 | return rc2; |
1648 | } |
1649 | return rc; |
1650 | } |
1651 | |
1652 | /* Check whether a task has a particular permission to an inode. |
1653 | The 'adp' parameter is optional and allows other audit |
1654 | data to be passed (e.g. the dentry). */ |
1655 | static int inode_has_perm(const struct cred *cred, |
1656 | struct inode *inode, |
1657 | u32 perms, |
1658 | struct common_audit_data *adp) |
1659 | { |
1660 | struct inode_security_struct *isec; |
1661 | u32 sid; |
1662 | |
1663 | validate_creds(cred); |
1664 | |
1665 | if (unlikely(IS_PRIVATE(inode))) |
1666 | return 0; |
1667 | |
1668 | sid = cred_sid(cred); |
1669 | isec = selinux_inode(inode); |
1670 | |
1671 | return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp); |
1672 | } |
1673 | |
1674 | /* Same as inode_has_perm, but pass explicit audit data containing |
1675 | the dentry to help the auditing code to more easily generate the |
1676 | pathname if needed. */ |
1677 | static inline int dentry_has_perm(const struct cred *cred, |
1678 | struct dentry *dentry, |
1679 | u32 av) |
1680 | { |
1681 | struct inode *inode = d_backing_inode(upper: dentry); |
1682 | struct common_audit_data ad; |
1683 | |
1684 | ad.type = LSM_AUDIT_DATA_DENTRY; |
1685 | ad.u.dentry = dentry; |
1686 | __inode_security_revalidate(inode, dentry, may_sleep: true); |
1687 | return inode_has_perm(cred, inode, perms: av, adp: &ad); |
1688 | } |
1689 | |
1690 | /* Same as inode_has_perm, but pass explicit audit data containing |
1691 | the path to help the auditing code to more easily generate the |
1692 | pathname if needed. */ |
1693 | static inline int path_has_perm(const struct cred *cred, |
1694 | const struct path *path, |
1695 | u32 av) |
1696 | { |
1697 | struct inode *inode = d_backing_inode(upper: path->dentry); |
1698 | struct common_audit_data ad; |
1699 | |
1700 | ad.type = LSM_AUDIT_DATA_PATH; |
1701 | ad.u.path = *path; |
1702 | __inode_security_revalidate(inode, dentry: path->dentry, may_sleep: true); |
1703 | return inode_has_perm(cred, inode, perms: av, adp: &ad); |
1704 | } |
1705 | |
1706 | /* Same as path_has_perm, but uses the inode from the file struct. */ |
1707 | static inline int file_path_has_perm(const struct cred *cred, |
1708 | struct file *file, |
1709 | u32 av) |
1710 | { |
1711 | struct common_audit_data ad; |
1712 | |
1713 | ad.type = LSM_AUDIT_DATA_FILE; |
1714 | ad.u.file = file; |
1715 | return inode_has_perm(cred, inode: file_inode(f: file), perms: av, adp: &ad); |
1716 | } |
1717 | |
1718 | #ifdef CONFIG_BPF_SYSCALL |
1719 | static int bpf_fd_pass(const struct file *file, u32 sid); |
1720 | #endif |
1721 | |
1722 | /* Check whether a task can use an open file descriptor to |
1723 | access an inode in a given way. Check access to the |
1724 | descriptor itself, and then use dentry_has_perm to |
1725 | check a particular permission to the file. |
1726 | Access to the descriptor is implicitly granted if it |
1727 | has the same SID as the process. If av is zero, then |
1728 | access to the file is not checked, e.g. for cases |
1729 | where only the descriptor is affected like seek. */ |
1730 | static int file_has_perm(const struct cred *cred, |
1731 | struct file *file, |
1732 | u32 av) |
1733 | { |
1734 | struct file_security_struct *fsec = selinux_file(file); |
1735 | struct inode *inode = file_inode(f: file); |
1736 | struct common_audit_data ad; |
1737 | u32 sid = cred_sid(cred); |
1738 | int rc; |
1739 | |
1740 | ad.type = LSM_AUDIT_DATA_FILE; |
1741 | ad.u.file = file; |
1742 | |
1743 | if (sid != fsec->sid) { |
1744 | rc = avc_has_perm(sid, fsec->sid, |
1745 | SECCLASS_FD, |
1746 | FD__USE, |
1747 | &ad); |
1748 | if (rc) |
1749 | goto out; |
1750 | } |
1751 | |
1752 | #ifdef CONFIG_BPF_SYSCALL |
1753 | rc = bpf_fd_pass(file, sid: cred_sid(cred)); |
1754 | if (rc) |
1755 | return rc; |
1756 | #endif |
1757 | |
1758 | /* av is zero if only checking access to the descriptor. */ |
1759 | rc = 0; |
1760 | if (av) |
1761 | rc = inode_has_perm(cred, inode, perms: av, adp: &ad); |
1762 | |
1763 | out: |
1764 | return rc; |
1765 | } |
1766 | |
1767 | /* |
1768 | * Determine the label for an inode that might be unioned. |
1769 | */ |
1770 | static int |
1771 | selinux_determine_inode_label(const struct task_security_struct *tsec, |
1772 | struct inode *dir, |
1773 | const struct qstr *name, u16 tclass, |
1774 | u32 *_new_isid) |
1775 | { |
1776 | const struct superblock_security_struct *sbsec = |
1777 | selinux_superblock(dir->i_sb); |
1778 | |
1779 | if ((sbsec->flags & SE_SBINITIALIZED) && |
1780 | (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) { |
1781 | *_new_isid = sbsec->mntpoint_sid; |
1782 | } else if ((sbsec->flags & SBLABEL_MNT) && |
1783 | tsec->create_sid) { |
1784 | *_new_isid = tsec->create_sid; |
1785 | } else { |
1786 | const struct inode_security_struct *dsec = inode_security(inode: dir); |
1787 | return security_transition_sid(tsec->sid, |
1788 | dsec->sid, tclass, |
1789 | name, _new_isid); |
1790 | } |
1791 | |
1792 | return 0; |
1793 | } |
1794 | |
1795 | /* Check whether a task can create a file. */ |
1796 | static int may_create(struct inode *dir, |
1797 | struct dentry *dentry, |
1798 | u16 tclass) |
1799 | { |
1800 | const struct task_security_struct *tsec = selinux_cred(current_cred()); |
1801 | struct inode_security_struct *dsec; |
1802 | struct superblock_security_struct *sbsec; |
1803 | u32 sid, newsid; |
1804 | struct common_audit_data ad; |
1805 | int rc; |
1806 | |
1807 | dsec = inode_security(inode: dir); |
1808 | sbsec = selinux_superblock(dir->i_sb); |
1809 | |
1810 | sid = tsec->sid; |
1811 | |
1812 | ad.type = LSM_AUDIT_DATA_DENTRY; |
1813 | ad.u.dentry = dentry; |
1814 | |
1815 | rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, |
1816 | DIR__ADD_NAME | DIR__SEARCH, |
1817 | &ad); |
1818 | if (rc) |
1819 | return rc; |
1820 | |
1821 | rc = selinux_determine_inode_label(tsec, dir, name: &dentry->d_name, tclass, |
1822 | new_isid: &newsid); |
1823 | if (rc) |
1824 | return rc; |
1825 | |
1826 | rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad); |
1827 | if (rc) |
1828 | return rc; |
1829 | |
1830 | return avc_has_perm(newsid, sbsec->sid, |
1831 | SECCLASS_FILESYSTEM, |
1832 | FILESYSTEM__ASSOCIATE, &ad); |
1833 | } |
1834 | |
1835 | #define MAY_LINK 0 |
1836 | #define MAY_UNLINK 1 |
1837 | #define MAY_RMDIR 2 |
1838 | |
1839 | /* Check whether a task can link, unlink, or rmdir a file/directory. */ |
1840 | static int may_link(struct inode *dir, |
1841 | struct dentry *dentry, |
1842 | int kind) |
1843 | |
1844 | { |
1845 | struct inode_security_struct *dsec, *isec; |
1846 | struct common_audit_data ad; |
1847 | u32 sid = current_sid(); |
1848 | u32 av; |
1849 | int rc; |
1850 | |
1851 | dsec = inode_security(inode: dir); |
1852 | isec = backing_inode_security(dentry); |
1853 | |
1854 | ad.type = LSM_AUDIT_DATA_DENTRY; |
1855 | ad.u.dentry = dentry; |
1856 | |
1857 | av = DIR__SEARCH; |
1858 | av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME); |
1859 | rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad); |
1860 | if (rc) |
1861 | return rc; |
1862 | |
1863 | switch (kind) { |
1864 | case MAY_LINK: |
1865 | av = FILE__LINK; |
1866 | break; |
1867 | case MAY_UNLINK: |
1868 | av = FILE__UNLINK; |
1869 | break; |
1870 | case MAY_RMDIR: |
1871 | av = DIR__RMDIR; |
1872 | break; |
1873 | default: |
1874 | pr_warn("SELinux: %s: unrecognized kind %d\n" , |
1875 | __func__, kind); |
1876 | return 0; |
1877 | } |
1878 | |
1879 | rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad); |
1880 | return rc; |
1881 | } |
1882 | |
1883 | static inline int may_rename(struct inode *old_dir, |
1884 | struct dentry *old_dentry, |
1885 | struct inode *new_dir, |
1886 | struct dentry *new_dentry) |
1887 | { |
1888 | struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec; |
1889 | struct common_audit_data ad; |
1890 | u32 sid = current_sid(); |
1891 | u32 av; |
1892 | int old_is_dir, new_is_dir; |
1893 | int rc; |
1894 | |
1895 | old_dsec = inode_security(inode: old_dir); |
1896 | old_isec = backing_inode_security(dentry: old_dentry); |
1897 | old_is_dir = d_is_dir(dentry: old_dentry); |
1898 | new_dsec = inode_security(inode: new_dir); |
1899 | |
1900 | ad.type = LSM_AUDIT_DATA_DENTRY; |
1901 | |
1902 | ad.u.dentry = old_dentry; |
1903 | rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR, |
1904 | DIR__REMOVE_NAME | DIR__SEARCH, &ad); |
1905 | if (rc) |
1906 | return rc; |
1907 | rc = avc_has_perm(sid, old_isec->sid, |
1908 | old_isec->sclass, FILE__RENAME, &ad); |
1909 | if (rc) |
1910 | return rc; |
1911 | if (old_is_dir && new_dir != old_dir) { |
1912 | rc = avc_has_perm(sid, old_isec->sid, |
1913 | old_isec->sclass, DIR__REPARENT, &ad); |
1914 | if (rc) |
1915 | return rc; |
1916 | } |
1917 | |
1918 | ad.u.dentry = new_dentry; |
1919 | av = DIR__ADD_NAME | DIR__SEARCH; |
1920 | if (d_is_positive(new_dentry)) |
1921 | av |= DIR__REMOVE_NAME; |
1922 | rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad); |
1923 | if (rc) |
1924 | return rc; |
1925 | if (d_is_positive(dentry: new_dentry)) { |
1926 | new_isec = backing_inode_security(dentry: new_dentry); |
1927 | new_is_dir = d_is_dir(dentry: new_dentry); |
1928 | rc = avc_has_perm(sid, new_isec->sid, |
1929 | new_isec->sclass, |
1930 | (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad); |
1931 | if (rc) |
1932 | return rc; |
1933 | } |
1934 | |
1935 | return 0; |
1936 | } |
1937 | |
1938 | /* Check whether a task can perform a filesystem operation. */ |
1939 | static int superblock_has_perm(const struct cred *cred, |
1940 | const struct super_block *sb, |
1941 | u32 perms, |
1942 | struct common_audit_data *ad) |
1943 | { |
1944 | struct superblock_security_struct *sbsec; |
1945 | u32 sid = cred_sid(cred); |
1946 | |
1947 | sbsec = selinux_superblock(sb); |
1948 | return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad); |
1949 | } |
1950 | |
1951 | /* Convert a Linux mode and permission mask to an access vector. */ |
1952 | static inline u32 file_mask_to_av(int mode, int mask) |
1953 | { |
1954 | u32 av = 0; |
1955 | |
1956 | if (!S_ISDIR(mode)) { |
1957 | if (mask & MAY_EXEC) |
1958 | av |= FILE__EXECUTE; |
1959 | if (mask & MAY_READ) |
1960 | av |= FILE__READ; |
1961 | |
1962 | if (mask & MAY_APPEND) |
1963 | av |= FILE__APPEND; |
1964 | else if (mask & MAY_WRITE) |
1965 | av |= FILE__WRITE; |
1966 | |
1967 | } else { |
1968 | if (mask & MAY_EXEC) |
1969 | av |= DIR__SEARCH; |
1970 | if (mask & MAY_WRITE) |
1971 | av |= DIR__WRITE; |
1972 | if (mask & MAY_READ) |
1973 | av |= DIR__READ; |
1974 | } |
1975 | |
1976 | return av; |
1977 | } |
1978 | |
1979 | /* Convert a Linux file to an access vector. */ |
1980 | static inline u32 file_to_av(const struct file *file) |
1981 | { |
1982 | u32 av = 0; |
1983 | |
1984 | if (file->f_mode & FMODE_READ) |
1985 | av |= FILE__READ; |
1986 | if (file->f_mode & FMODE_WRITE) { |
1987 | if (file->f_flags & O_APPEND) |
1988 | av |= FILE__APPEND; |
1989 | else |
1990 | av |= FILE__WRITE; |
1991 | } |
1992 | if (!av) { |
1993 | /* |
1994 | * Special file opened with flags 3 for ioctl-only use. |
1995 | */ |
1996 | av = FILE__IOCTL; |
1997 | } |
1998 | |
1999 | return av; |
2000 | } |
2001 | |
2002 | /* |
2003 | * Convert a file to an access vector and include the correct |
2004 | * open permission. |
2005 | */ |
2006 | static inline u32 open_file_to_av(struct file *file) |
2007 | { |
2008 | u32 av = file_to_av(file); |
2009 | struct inode *inode = file_inode(f: file); |
2010 | |
2011 | if (selinux_policycap_openperm() && |
2012 | inode->i_sb->s_magic != SOCKFS_MAGIC) |
2013 | av |= FILE__OPEN; |
2014 | |
2015 | return av; |
2016 | } |
2017 | |
2018 | /* Hook functions begin here. */ |
2019 | |
2020 | static int selinux_binder_set_context_mgr(const struct cred *mgr) |
2021 | { |
2022 | return avc_has_perm(current_sid(), cred_sid(mgr), SECCLASS_BINDER, |
2023 | BINDER__SET_CONTEXT_MGR, NULL); |
2024 | } |
2025 | |
2026 | static int selinux_binder_transaction(const struct cred *from, |
2027 | const struct cred *to) |
2028 | { |
2029 | u32 mysid = current_sid(); |
2030 | u32 fromsid = cred_sid(cred: from); |
2031 | u32 tosid = cred_sid(cred: to); |
2032 | int rc; |
2033 | |
2034 | if (mysid != fromsid) { |
2035 | rc = avc_has_perm(mysid, fromsid, SECCLASS_BINDER, |
2036 | BINDER__IMPERSONATE, NULL); |
2037 | if (rc) |
2038 | return rc; |
2039 | } |
2040 | |
2041 | return avc_has_perm(fromsid, tosid, |
2042 | SECCLASS_BINDER, BINDER__CALL, NULL); |
2043 | } |
2044 | |
2045 | static int selinux_binder_transfer_binder(const struct cred *from, |
2046 | const struct cred *to) |
2047 | { |
2048 | return avc_has_perm(cred_sid(from), cred_sid(to), |
2049 | SECCLASS_BINDER, BINDER__TRANSFER, |
2050 | NULL); |
2051 | } |
2052 | |
2053 | static int selinux_binder_transfer_file(const struct cred *from, |
2054 | const struct cred *to, |
2055 | const struct file *file) |
2056 | { |
2057 | u32 sid = cred_sid(cred: to); |
2058 | struct file_security_struct *fsec = selinux_file(file); |
2059 | struct dentry *dentry = file->f_path.dentry; |
2060 | struct inode_security_struct *isec; |
2061 | struct common_audit_data ad; |
2062 | int rc; |
2063 | |
2064 | ad.type = LSM_AUDIT_DATA_PATH; |
2065 | ad.u.path = file->f_path; |
2066 | |
2067 | if (sid != fsec->sid) { |
2068 | rc = avc_has_perm(sid, fsec->sid, |
2069 | SECCLASS_FD, |
2070 | FD__USE, |
2071 | &ad); |
2072 | if (rc) |
2073 | return rc; |
2074 | } |
2075 | |
2076 | #ifdef CONFIG_BPF_SYSCALL |
2077 | rc = bpf_fd_pass(file, sid); |
2078 | if (rc) |
2079 | return rc; |
2080 | #endif |
2081 | |
2082 | if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) |
2083 | return 0; |
2084 | |
2085 | isec = backing_inode_security(dentry); |
2086 | return avc_has_perm(sid, isec->sid, isec->sclass, file_to_av(file), |
2087 | &ad); |
2088 | } |
2089 | |
2090 | static int selinux_ptrace_access_check(struct task_struct *child, |
2091 | unsigned int mode) |
2092 | { |
2093 | u32 sid = current_sid(); |
2094 | u32 csid = task_sid_obj(task: child); |
2095 | |
2096 | if (mode & PTRACE_MODE_READ) |
2097 | return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, |
2098 | NULL); |
2099 | |
2100 | return avc_has_perm(sid, csid, SECCLASS_PROCESS, PROCESS__PTRACE, |
2101 | NULL); |
2102 | } |
2103 | |
2104 | static int selinux_ptrace_traceme(struct task_struct *parent) |
2105 | { |
2106 | return avc_has_perm(task_sid_obj(parent), task_sid_obj(current), |
2107 | SECCLASS_PROCESS, PROCESS__PTRACE, NULL); |
2108 | } |
2109 | |
2110 | static int selinux_capget(const struct task_struct *target, kernel_cap_t *effective, |
2111 | kernel_cap_t *inheritable, kernel_cap_t *permitted) |
2112 | { |
2113 | return avc_has_perm(current_sid(), task_sid_obj(target), |
2114 | SECCLASS_PROCESS, PROCESS__GETCAP, NULL); |
2115 | } |
2116 | |
2117 | static int selinux_capset(struct cred *new, const struct cred *old, |
2118 | const kernel_cap_t *effective, |
2119 | const kernel_cap_t *inheritable, |
2120 | const kernel_cap_t *permitted) |
2121 | { |
2122 | return avc_has_perm(cred_sid(old), cred_sid(new), SECCLASS_PROCESS, |
2123 | PROCESS__SETCAP, NULL); |
2124 | } |
2125 | |
2126 | /* |
2127 | * (This comment used to live with the selinux_task_setuid hook, |
2128 | * which was removed). |
2129 | * |
2130 | * Since setuid only affects the current process, and since the SELinux |
2131 | * controls are not based on the Linux identity attributes, SELinux does not |
2132 | * need to control this operation. However, SELinux does control the use of |
2133 | * the CAP_SETUID and CAP_SETGID capabilities using the capable hook. |
2134 | */ |
2135 | |
2136 | static int selinux_capable(const struct cred *cred, struct user_namespace *ns, |
2137 | int cap, unsigned int opts) |
2138 | { |
2139 | return cred_has_capability(cred, cap, opts, initns: ns == &init_user_ns); |
2140 | } |
2141 | |
2142 | static int selinux_quotactl(int cmds, int type, int id, const struct super_block *sb) |
2143 | { |
2144 | const struct cred *cred = current_cred(); |
2145 | int rc = 0; |
2146 | |
2147 | if (!sb) |
2148 | return 0; |
2149 | |
2150 | switch (cmds) { |
2151 | case Q_SYNC: |
2152 | case Q_QUOTAON: |
2153 | case Q_QUOTAOFF: |
2154 | case Q_SETINFO: |
2155 | case Q_SETQUOTA: |
2156 | case Q_XQUOTAOFF: |
2157 | case Q_XQUOTAON: |
2158 | case Q_XSETQLIM: |
2159 | rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL); |
2160 | break; |
2161 | case Q_GETFMT: |
2162 | case Q_GETINFO: |
2163 | case Q_GETQUOTA: |
2164 | case Q_XGETQUOTA: |
2165 | case Q_XGETQSTAT: |
2166 | case Q_XGETQSTATV: |
2167 | case Q_XGETNEXTQUOTA: |
2168 | rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL); |
2169 | break; |
2170 | default: |
2171 | rc = 0; /* let the kernel handle invalid cmds */ |
2172 | break; |
2173 | } |
2174 | return rc; |
2175 | } |
2176 | |
2177 | static int selinux_quota_on(struct dentry *dentry) |
2178 | { |
2179 | const struct cred *cred = current_cred(); |
2180 | |
2181 | return dentry_has_perm(cred, dentry, FILE__QUOTAON); |
2182 | } |
2183 | |
2184 | static int selinux_syslog(int type) |
2185 | { |
2186 | switch (type) { |
2187 | case SYSLOG_ACTION_READ_ALL: /* Read last kernel messages */ |
2188 | case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */ |
2189 | return avc_has_perm(current_sid(), SECINITSID_KERNEL, |
2190 | SECCLASS_SYSTEM, SYSTEM__SYSLOG_READ, NULL); |
2191 | case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */ |
2192 | case SYSLOG_ACTION_CONSOLE_ON: /* Enable logging to console */ |
2193 | /* Set level of messages printed to console */ |
2194 | case SYSLOG_ACTION_CONSOLE_LEVEL: |
2195 | return avc_has_perm(current_sid(), SECINITSID_KERNEL, |
2196 | SECCLASS_SYSTEM, SYSTEM__SYSLOG_CONSOLE, |
2197 | NULL); |
2198 | } |
2199 | /* All other syslog types */ |
2200 | return avc_has_perm(current_sid(), SECINITSID_KERNEL, |
2201 | SECCLASS_SYSTEM, SYSTEM__SYSLOG_MOD, NULL); |
2202 | } |
2203 | |
2204 | /* |
2205 | * Check that a process has enough memory to allocate a new virtual |
2206 | * mapping. 0 means there is enough memory for the allocation to |
2207 | * succeed and -ENOMEM implies there is not. |
2208 | * |
2209 | * Do not audit the selinux permission check, as this is applied to all |
2210 | * processes that allocate mappings. |
2211 | */ |
2212 | static int selinux_vm_enough_memory(struct mm_struct *mm, long pages) |
2213 | { |
2214 | int rc, cap_sys_admin = 0; |
2215 | |
2216 | rc = cred_has_capability(current_cred(), CAP_SYS_ADMIN, |
2217 | CAP_OPT_NOAUDIT, initns: true); |
2218 | if (rc == 0) |
2219 | cap_sys_admin = 1; |
2220 | |
2221 | return cap_sys_admin; |
2222 | } |
2223 | |
2224 | /* binprm security operations */ |
2225 | |
2226 | static u32 ptrace_parent_sid(void) |
2227 | { |
2228 | u32 sid = 0; |
2229 | struct task_struct *tracer; |
2230 | |
2231 | rcu_read_lock(); |
2232 | tracer = ptrace_parent(current); |
2233 | if (tracer) |
2234 | sid = task_sid_obj(task: tracer); |
2235 | rcu_read_unlock(); |
2236 | |
2237 | return sid; |
2238 | } |
2239 | |
2240 | static int check_nnp_nosuid(const struct linux_binprm *bprm, |
2241 | const struct task_security_struct *old_tsec, |
2242 | const struct task_security_struct *new_tsec) |
2243 | { |
2244 | int nnp = (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS); |
2245 | int nosuid = !mnt_may_suid(mnt: bprm->file->f_path.mnt); |
2246 | int rc; |
2247 | u32 av; |
2248 | |
2249 | if (!nnp && !nosuid) |
2250 | return 0; /* neither NNP nor nosuid */ |
2251 | |
2252 | if (new_tsec->sid == old_tsec->sid) |
2253 | return 0; /* No change in credentials */ |
2254 | |
2255 | /* |
2256 | * If the policy enables the nnp_nosuid_transition policy capability, |
2257 | * then we permit transitions under NNP or nosuid if the |
2258 | * policy allows the corresponding permission between |
2259 | * the old and new contexts. |
2260 | */ |
2261 | if (selinux_policycap_nnp_nosuid_transition()) { |
2262 | av = 0; |
2263 | if (nnp) |
2264 | av |= PROCESS2__NNP_TRANSITION; |
2265 | if (nosuid) |
2266 | av |= PROCESS2__NOSUID_TRANSITION; |
2267 | rc = avc_has_perm(old_tsec->sid, new_tsec->sid, |
2268 | SECCLASS_PROCESS2, av, NULL); |
2269 | if (!rc) |
2270 | return 0; |
2271 | } |
2272 | |
2273 | /* |
2274 | * We also permit NNP or nosuid transitions to bounded SIDs, |
2275 | * i.e. SIDs that are guaranteed to only be allowed a subset |
2276 | * of the permissions of the current SID. |
2277 | */ |
2278 | rc = security_bounded_transition(old_tsec->sid, |
2279 | new_tsec->sid); |
2280 | if (!rc) |
2281 | return 0; |
2282 | |
2283 | /* |
2284 | * On failure, preserve the errno values for NNP vs nosuid. |
2285 | * NNP: Operation not permitted for caller. |
2286 | * nosuid: Permission denied to file. |
2287 | */ |
2288 | if (nnp) |
2289 | return -EPERM; |
2290 | return -EACCES; |
2291 | } |
2292 | |
2293 | static int selinux_bprm_creds_for_exec(struct linux_binprm *bprm) |
2294 | { |
2295 | const struct task_security_struct *old_tsec; |
2296 | struct task_security_struct *new_tsec; |
2297 | struct inode_security_struct *isec; |
2298 | struct common_audit_data ad; |
2299 | struct inode *inode = file_inode(f: bprm->file); |
2300 | int rc; |
2301 | |
2302 | /* SELinux context only depends on initial program or script and not |
2303 | * the script interpreter */ |
2304 | |
2305 | old_tsec = selinux_cred(current_cred()); |
2306 | new_tsec = selinux_cred(bprm->cred); |
2307 | isec = inode_security(inode); |
2308 | |
2309 | /* Default to the current task SID. */ |
2310 | new_tsec->sid = old_tsec->sid; |
2311 | new_tsec->osid = old_tsec->sid; |
2312 | |
2313 | /* Reset fs, key, and sock SIDs on execve. */ |
2314 | new_tsec->create_sid = 0; |
2315 | new_tsec->keycreate_sid = 0; |
2316 | new_tsec->sockcreate_sid = 0; |
2317 | |
2318 | if (old_tsec->exec_sid) { |
2319 | new_tsec->sid = old_tsec->exec_sid; |
2320 | /* Reset exec SID on execve. */ |
2321 | new_tsec->exec_sid = 0; |
2322 | |
2323 | /* Fail on NNP or nosuid if not an allowed transition. */ |
2324 | rc = check_nnp_nosuid(bprm, old_tsec, new_tsec); |
2325 | if (rc) |
2326 | return rc; |
2327 | } else { |
2328 | /* Check for a default transition on this program. */ |
2329 | rc = security_transition_sid(old_tsec->sid, |
2330 | isec->sid, SECCLASS_PROCESS, NULL, |
2331 | &new_tsec->sid); |
2332 | if (rc) |
2333 | return rc; |
2334 | |
2335 | /* |
2336 | * Fallback to old SID on NNP or nosuid if not an allowed |
2337 | * transition. |
2338 | */ |
2339 | rc = check_nnp_nosuid(bprm, old_tsec, new_tsec); |
2340 | if (rc) |
2341 | new_tsec->sid = old_tsec->sid; |
2342 | } |
2343 | |
2344 | ad.type = LSM_AUDIT_DATA_FILE; |
2345 | ad.u.file = bprm->file; |
2346 | |
2347 | if (new_tsec->sid == old_tsec->sid) { |
2348 | rc = avc_has_perm(old_tsec->sid, isec->sid, |
2349 | SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad); |
2350 | if (rc) |
2351 | return rc; |
2352 | } else { |
2353 | /* Check permissions for the transition. */ |
2354 | rc = avc_has_perm(old_tsec->sid, new_tsec->sid, |
2355 | SECCLASS_PROCESS, PROCESS__TRANSITION, &ad); |
2356 | if (rc) |
2357 | return rc; |
2358 | |
2359 | rc = avc_has_perm(new_tsec->sid, isec->sid, |
2360 | SECCLASS_FILE, FILE__ENTRYPOINT, &ad); |
2361 | if (rc) |
2362 | return rc; |
2363 | |
2364 | /* Check for shared state */ |
2365 | if (bprm->unsafe & LSM_UNSAFE_SHARE) { |
2366 | rc = avc_has_perm(old_tsec->sid, new_tsec->sid, |
2367 | SECCLASS_PROCESS, PROCESS__SHARE, |
2368 | NULL); |
2369 | if (rc) |
2370 | return -EPERM; |
2371 | } |
2372 | |
2373 | /* Make sure that anyone attempting to ptrace over a task that |
2374 | * changes its SID has the appropriate permit */ |
2375 | if (bprm->unsafe & LSM_UNSAFE_PTRACE) { |
2376 | u32 ptsid = ptrace_parent_sid(); |
2377 | if (ptsid != 0) { |
2378 | rc = avc_has_perm(ptsid, new_tsec->sid, |
2379 | SECCLASS_PROCESS, |
2380 | PROCESS__PTRACE, NULL); |
2381 | if (rc) |
2382 | return -EPERM; |
2383 | } |
2384 | } |
2385 | |
2386 | /* Clear any possibly unsafe personality bits on exec: */ |
2387 | bprm->per_clear |= PER_CLEAR_ON_SETID; |
2388 | |
2389 | /* Enable secure mode for SIDs transitions unless |
2390 | the noatsecure permission is granted between |
2391 | the two SIDs, i.e. ahp returns 0. */ |
2392 | rc = avc_has_perm(old_tsec->sid, new_tsec->sid, |
2393 | SECCLASS_PROCESS, PROCESS__NOATSECURE, |
2394 | NULL); |
2395 | bprm->secureexec |= !!rc; |
2396 | } |
2397 | |
2398 | return 0; |
2399 | } |
2400 | |
2401 | static int match_file(const void *p, struct file *file, unsigned fd) |
2402 | { |
2403 | return file_has_perm(cred: p, file, av: file_to_av(file)) ? fd + 1 : 0; |
2404 | } |
2405 | |
2406 | /* Derived from fs/exec.c:flush_old_files. */ |
2407 | static inline void flush_unauthorized_files(const struct cred *cred, |
2408 | struct files_struct *files) |
2409 | { |
2410 | struct file *file, *devnull = NULL; |
2411 | struct tty_struct *tty; |
2412 | int drop_tty = 0; |
2413 | unsigned n; |
2414 | |
2415 | tty = get_current_tty(); |
2416 | if (tty) { |
2417 | spin_lock(lock: &tty->files_lock); |
2418 | if (!list_empty(head: &tty->tty_files)) { |
2419 | struct tty_file_private *file_priv; |
2420 | |
2421 | /* Revalidate access to controlling tty. |
2422 | Use file_path_has_perm on the tty path directly |
2423 | rather than using file_has_perm, as this particular |
2424 | open file may belong to another process and we are |
2425 | only interested in the inode-based check here. */ |
2426 | file_priv = list_first_entry(&tty->tty_files, |
2427 | struct tty_file_private, list); |
2428 | file = file_priv->file; |
2429 | if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE)) |
2430 | drop_tty = 1; |
2431 | } |
2432 | spin_unlock(lock: &tty->files_lock); |
2433 | tty_kref_put(tty); |
2434 | } |
2435 | /* Reset controlling tty. */ |
2436 | if (drop_tty) |
2437 | no_tty(); |
2438 | |
2439 | /* Revalidate access to inherited open files. */ |
2440 | n = iterate_fd(files, 0, match_file, cred); |
2441 | if (!n) /* none found? */ |
2442 | return; |
2443 | |
2444 | devnull = dentry_open(&selinux_null, O_RDWR, cred); |
2445 | if (IS_ERR(ptr: devnull)) |
2446 | devnull = NULL; |
2447 | /* replace all the matching ones with this */ |
2448 | do { |
2449 | replace_fd(fd: n - 1, file: devnull, flags: 0); |
2450 | } while ((n = iterate_fd(files, n, match_file, cred)) != 0); |
2451 | if (devnull) |
2452 | fput(devnull); |
2453 | } |
2454 | |
2455 | /* |
2456 | * Prepare a process for imminent new credential changes due to exec |
2457 | */ |
2458 | static void selinux_bprm_committing_creds(const struct linux_binprm *bprm) |
2459 | { |
2460 | struct task_security_struct *new_tsec; |
2461 | struct rlimit *rlim, *initrlim; |
2462 | int rc, i; |
2463 | |
2464 | new_tsec = selinux_cred(bprm->cred); |
2465 | if (new_tsec->sid == new_tsec->osid) |
2466 | return; |
2467 | |
2468 | /* Close files for which the new task SID is not authorized. */ |
2469 | flush_unauthorized_files(cred: bprm->cred, current->files); |
2470 | |
2471 | /* Always clear parent death signal on SID transitions. */ |
2472 | current->pdeath_signal = 0; |
2473 | |
2474 | /* Check whether the new SID can inherit resource limits from the old |
2475 | * SID. If not, reset all soft limits to the lower of the current |
2476 | * task's hard limit and the init task's soft limit. |
2477 | * |
2478 | * Note that the setting of hard limits (even to lower them) can be |
2479 | * controlled by the setrlimit check. The inclusion of the init task's |
2480 | * soft limit into the computation is to avoid resetting soft limits |
2481 | * higher than the default soft limit for cases where the default is |
2482 | * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK. |
2483 | */ |
2484 | rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS, |
2485 | PROCESS__RLIMITINH, NULL); |
2486 | if (rc) { |
2487 | /* protect against do_prlimit() */ |
2488 | task_lock(current); |
2489 | for (i = 0; i < RLIM_NLIMITS; i++) { |
2490 | rlim = current->signal->rlim + i; |
2491 | initrlim = init_task.signal->rlim + i; |
2492 | rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur); |
2493 | } |
2494 | task_unlock(current); |
2495 | if (IS_ENABLED(CONFIG_POSIX_TIMERS)) |
2496 | update_rlimit_cpu(current, rlim_new: rlimit(RLIMIT_CPU)); |
2497 | } |
2498 | } |
2499 | |
2500 | /* |
2501 | * Clean up the process immediately after the installation of new credentials |
2502 | * due to exec |
2503 | */ |
2504 | static void selinux_bprm_committed_creds(const struct linux_binprm *bprm) |
2505 | { |
2506 | const struct task_security_struct *tsec = selinux_cred(current_cred()); |
2507 | u32 osid, sid; |
2508 | int rc; |
2509 | |
2510 | osid = tsec->osid; |
2511 | sid = tsec->sid; |
2512 | |
2513 | if (sid == osid) |
2514 | return; |
2515 | |
2516 | /* Check whether the new SID can inherit signal state from the old SID. |
2517 | * If not, clear itimers to avoid subsequent signal generation and |
2518 | * flush and unblock signals. |
2519 | * |
2520 | * This must occur _after_ the task SID has been updated so that any |
2521 | * kill done after the flush will be checked against the new SID. |
2522 | */ |
2523 | rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL); |
2524 | if (rc) { |
2525 | clear_itimer(); |
2526 | |
2527 | spin_lock_irq(lock: &unrcu_pointer(current->sighand)->siglock); |
2528 | if (!fatal_signal_pending(current)) { |
2529 | flush_sigqueue(queue: ¤t->pending); |
2530 | flush_sigqueue(queue: ¤t->signal->shared_pending); |
2531 | flush_signal_handlers(current, force_default: 1); |
2532 | sigemptyset(set: ¤t->blocked); |
2533 | recalc_sigpending(); |
2534 | } |
2535 | spin_unlock_irq(lock: &unrcu_pointer(current->sighand)->siglock); |
2536 | } |
2537 | |
2538 | /* Wake up the parent if it is waiting so that it can recheck |
2539 | * wait permission to the new task SID. */ |
2540 | read_lock(&tasklist_lock); |
2541 | __wake_up_parent(current, unrcu_pointer(current->real_parent)); |
2542 | read_unlock(&tasklist_lock); |
2543 | } |
2544 | |
2545 | /* superblock security operations */ |
2546 | |
2547 | static int selinux_sb_alloc_security(struct super_block *sb) |
2548 | { |
2549 | struct superblock_security_struct *sbsec = selinux_superblock(sb); |
2550 | |
2551 | mutex_init(&sbsec->lock); |
2552 | INIT_LIST_HEAD(list: &sbsec->isec_head); |
2553 | spin_lock_init(&sbsec->isec_lock); |
2554 | sbsec->sid = SECINITSID_UNLABELED; |
2555 | sbsec->def_sid = SECINITSID_FILE; |
2556 | sbsec->mntpoint_sid = SECINITSID_UNLABELED; |
2557 | |
2558 | return 0; |
2559 | } |
2560 | |
2561 | static inline int opt_len(const char *s) |
2562 | { |
2563 | bool open_quote = false; |
2564 | int len; |
2565 | char c; |
2566 | |
2567 | for (len = 0; (c = s[len]) != '\0'; len++) { |
2568 | if (c == '"') |
2569 | open_quote = !open_quote; |
2570 | if (c == ',' && !open_quote) |
2571 | break; |
2572 | } |
2573 | return len; |
2574 | } |
2575 | |
2576 | static int selinux_sb_eat_lsm_opts(char *options, void **mnt_opts) |
2577 | { |
2578 | char *from = options; |
2579 | char *to = options; |
2580 | bool first = true; |
2581 | int rc; |
2582 | |
2583 | while (1) { |
2584 | int len = opt_len(s: from); |
2585 | int token; |
2586 | char *arg = NULL; |
2587 | |
2588 | token = match_opt_prefix(s: from, l: len, arg: &arg); |
2589 | |
2590 | if (token != Opt_error) { |
2591 | char *p, *q; |
2592 | |
2593 | /* strip quotes */ |
2594 | if (arg) { |
2595 | for (p = q = arg; p < from + len; p++) { |
2596 | char c = *p; |
2597 | if (c != '"') |
2598 | *q++ = c; |
2599 | } |
2600 | arg = kmemdup_nul(s: arg, len: q - arg, GFP_KERNEL); |
2601 | if (!arg) { |
2602 | rc = -ENOMEM; |
2603 | goto free_opt; |
2604 | } |
2605 | } |
2606 | rc = selinux_add_opt(token, s: arg, mnt_opts); |
2607 | kfree(objp: arg); |
2608 | arg = NULL; |
2609 | if (unlikely(rc)) { |
2610 | goto free_opt; |
2611 | } |
2612 | } else { |
2613 | if (!first) { // copy with preceding comma |
2614 | from--; |
2615 | len++; |
2616 | } |
2617 | if (to != from) |
2618 | memmove(to, from, len); |
2619 | to += len; |
2620 | first = false; |
2621 | } |
2622 | if (!from[len]) |
2623 | break; |
2624 | from += len + 1; |
2625 | } |
2626 | *to = '\0'; |
2627 | return 0; |
2628 | |
2629 | free_opt: |
2630 | if (*mnt_opts) { |
2631 | selinux_free_mnt_opts(mnt_opts: *mnt_opts); |
2632 | *mnt_opts = NULL; |
2633 | } |
2634 | return rc; |
2635 | } |
2636 | |
2637 | static int selinux_sb_mnt_opts_compat(struct super_block *sb, void *mnt_opts) |
2638 | { |
2639 | struct selinux_mnt_opts *opts = mnt_opts; |
2640 | struct superblock_security_struct *sbsec = selinux_superblock(sb); |
2641 | |
2642 | /* |
2643 | * Superblock not initialized (i.e. no options) - reject if any |
2644 | * options specified, otherwise accept. |
2645 | */ |
2646 | if (!(sbsec->flags & SE_SBINITIALIZED)) |
2647 | return opts ? 1 : 0; |
2648 | |
2649 | /* |
2650 | * Superblock initialized and no options specified - reject if |
2651 | * superblock has any options set, otherwise accept. |
2652 | */ |
2653 | if (!opts) |
2654 | return (sbsec->flags & SE_MNTMASK) ? 1 : 0; |
2655 | |
2656 | if (opts->fscontext_sid) { |
2657 | if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, |
2658 | opts->fscontext_sid)) |
2659 | return 1; |
2660 | } |
2661 | if (opts->context_sid) { |
2662 | if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, |
2663 | opts->context_sid)) |
2664 | return 1; |
2665 | } |
2666 | if (opts->rootcontext_sid) { |
2667 | struct inode_security_struct *root_isec; |
2668 | |
2669 | root_isec = backing_inode_security(dentry: sb->s_root); |
2670 | if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, |
2671 | opts->rootcontext_sid)) |
2672 | return 1; |
2673 | } |
2674 | if (opts->defcontext_sid) { |
2675 | if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, |
2676 | opts->defcontext_sid)) |
2677 | return 1; |
2678 | } |
2679 | return 0; |
2680 | } |
2681 | |
2682 | static int selinux_sb_remount(struct super_block *sb, void *mnt_opts) |
2683 | { |
2684 | struct selinux_mnt_opts *opts = mnt_opts; |
2685 | struct superblock_security_struct *sbsec = selinux_superblock(sb); |
2686 | |
2687 | if (!(sbsec->flags & SE_SBINITIALIZED)) |
2688 | return 0; |
2689 | |
2690 | if (!opts) |
2691 | return 0; |
2692 | |
2693 | if (opts->fscontext_sid) { |
2694 | if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, |
2695 | opts->fscontext_sid)) |
2696 | goto out_bad_option; |
2697 | } |
2698 | if (opts->context_sid) { |
2699 | if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, |
2700 | opts->context_sid)) |
2701 | goto out_bad_option; |
2702 | } |
2703 | if (opts->rootcontext_sid) { |
2704 | struct inode_security_struct *root_isec; |
2705 | root_isec = backing_inode_security(dentry: sb->s_root); |
2706 | if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, |
2707 | opts->rootcontext_sid)) |
2708 | goto out_bad_option; |
2709 | } |
2710 | if (opts->defcontext_sid) { |
2711 | if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, |
2712 | opts->defcontext_sid)) |
2713 | goto out_bad_option; |
2714 | } |
2715 | return 0; |
2716 | |
2717 | out_bad_option: |
2718 | pr_warn("SELinux: unable to change security options " |
2719 | "during remount (dev %s, type=%s)\n" , sb->s_id, |
2720 | sb->s_type->name); |
2721 | return -EINVAL; |
2722 | } |
2723 | |
2724 | static int selinux_sb_kern_mount(const struct super_block *sb) |
2725 | { |
2726 | const struct cred *cred = current_cred(); |
2727 | struct common_audit_data ad; |
2728 | |
2729 | ad.type = LSM_AUDIT_DATA_DENTRY; |
2730 | ad.u.dentry = sb->s_root; |
2731 | return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad); |
2732 | } |
2733 | |
2734 | static int selinux_sb_statfs(struct dentry *dentry) |
2735 | { |
2736 | const struct cred *cred = current_cred(); |
2737 | struct common_audit_data ad; |
2738 | |
2739 | ad.type = LSM_AUDIT_DATA_DENTRY; |
2740 | ad.u.dentry = dentry->d_sb->s_root; |
2741 | return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad); |
2742 | } |
2743 | |
2744 | static int selinux_mount(const char *dev_name, |
2745 | const struct path *path, |
2746 | const char *type, |
2747 | unsigned long flags, |
2748 | void *data) |
2749 | { |
2750 | const struct cred *cred = current_cred(); |
2751 | |
2752 | if (flags & MS_REMOUNT) |
2753 | return superblock_has_perm(cred, path->dentry->d_sb, |
2754 | FILESYSTEM__REMOUNT, NULL); |
2755 | else |
2756 | return path_has_perm(cred, path, FILE__MOUNTON); |
2757 | } |
2758 | |
2759 | static int selinux_move_mount(const struct path *from_path, |
2760 | const struct path *to_path) |
2761 | { |
2762 | const struct cred *cred = current_cred(); |
2763 | |
2764 | return path_has_perm(cred, to_path, FILE__MOUNTON); |
2765 | } |
2766 | |
2767 | static int selinux_umount(struct vfsmount *mnt, int flags) |
2768 | { |
2769 | const struct cred *cred = current_cred(); |
2770 | |
2771 | return superblock_has_perm(cred, mnt->mnt_sb, |
2772 | FILESYSTEM__UNMOUNT, NULL); |
2773 | } |
2774 | |
2775 | static int selinux_fs_context_submount(struct fs_context *fc, |
2776 | struct super_block *reference) |
2777 | { |
2778 | const struct superblock_security_struct *sbsec = selinux_superblock(reference); |
2779 | struct selinux_mnt_opts *opts; |
2780 | |
2781 | /* |
2782 | * Ensure that fc->security remains NULL when no options are set |
2783 | * as expected by selinux_set_mnt_opts(). |
2784 | */ |
2785 | if (!(sbsec->flags & (FSCONTEXT_MNT|CONTEXT_MNT|DEFCONTEXT_MNT))) |
2786 | return 0; |
2787 | |
2788 | opts = kzalloc(size: sizeof(*opts), GFP_KERNEL); |
2789 | if (!opts) |
2790 | return -ENOMEM; |
2791 | |
2792 | if (sbsec->flags & FSCONTEXT_MNT) |
2793 | opts->fscontext_sid = sbsec->sid; |
2794 | if (sbsec->flags & CONTEXT_MNT) |
2795 | opts->context_sid = sbsec->mntpoint_sid; |
2796 | if (sbsec->flags & DEFCONTEXT_MNT) |
2797 | opts->defcontext_sid = sbsec->def_sid; |
2798 | fc->security = opts; |
2799 | return 0; |
2800 | } |
2801 | |
2802 | static int selinux_fs_context_dup(struct fs_context *fc, |
2803 | struct fs_context *src_fc) |
2804 | { |
2805 | const struct selinux_mnt_opts *src = src_fc->security; |
2806 | |
2807 | if (!src) |
2808 | return 0; |
2809 | |
2810 | fc->security = kmemdup(p: src, size: sizeof(*src), GFP_KERNEL); |
2811 | return fc->security ? 0 : -ENOMEM; |
2812 | } |
2813 | |
2814 | static const struct fs_parameter_spec selinux_fs_parameters[] = { |
2815 | fsparam_string(CONTEXT_STR, Opt_context), |
2816 | fsparam_string(DEFCONTEXT_STR, Opt_defcontext), |
2817 | fsparam_string(FSCONTEXT_STR, Opt_fscontext), |
2818 | fsparam_string(ROOTCONTEXT_STR, Opt_rootcontext), |
2819 | fsparam_flag (SECLABEL_STR, Opt_seclabel), |
2820 | {} |
2821 | }; |
2822 | |
2823 | static int selinux_fs_context_parse_param(struct fs_context *fc, |
2824 | struct fs_parameter *param) |
2825 | { |
2826 | struct fs_parse_result result; |
2827 | int opt; |
2828 | |
2829 | opt = fs_parse(fc, desc: selinux_fs_parameters, param, result: &result); |
2830 | if (opt < 0) |
2831 | return opt; |
2832 | |
2833 | return selinux_add_opt(token: opt, s: param->string, mnt_opts: &fc->security); |
2834 | } |
2835 | |
2836 | /* inode security operations */ |
2837 | |
2838 | static int selinux_inode_alloc_security(struct inode *inode) |
2839 | { |
2840 | struct inode_security_struct *isec = selinux_inode(inode); |
2841 | u32 sid = current_sid(); |
2842 | |
2843 | spin_lock_init(&isec->lock); |
2844 | INIT_LIST_HEAD(list: &isec->list); |
2845 | isec->inode = inode; |
2846 | isec->sid = SECINITSID_UNLABELED; |
2847 | isec->sclass = SECCLASS_FILE; |
2848 | isec->task_sid = sid; |
2849 | isec->initialized = LABEL_INVALID; |
2850 | |
2851 | return 0; |
2852 | } |
2853 | |
2854 | static void selinux_inode_free_security(struct inode *inode) |
2855 | { |
2856 | inode_free_security(inode); |
2857 | } |
2858 | |
2859 | static int selinux_dentry_init_security(struct dentry *dentry, int mode, |
2860 | const struct qstr *name, |
2861 | const char **xattr_name, void **ctx, |
2862 | u32 *ctxlen) |
2863 | { |
2864 | u32 newsid; |
2865 | int rc; |
2866 | |
2867 | rc = selinux_determine_inode_label(tsec: selinux_cred(current_cred()), |
2868 | dir: d_inode(dentry: dentry->d_parent), name, |
2869 | tclass: inode_mode_to_security_class(mode), |
2870 | new_isid: &newsid); |
2871 | if (rc) |
2872 | return rc; |
2873 | |
2874 | if (xattr_name) |
2875 | *xattr_name = XATTR_NAME_SELINUX; |
2876 | |
2877 | return security_sid_to_context(newsid, (char **)ctx, |
2878 | ctxlen); |
2879 | } |
2880 | |
2881 | static int selinux_dentry_create_files_as(struct dentry *dentry, int mode, |
2882 | struct qstr *name, |
2883 | const struct cred *old, |
2884 | struct cred *new) |
2885 | { |
2886 | u32 newsid; |
2887 | int rc; |
2888 | struct task_security_struct *tsec; |
2889 | |
2890 | rc = selinux_determine_inode_label(tsec: selinux_cred(old), |
2891 | dir: d_inode(dentry: dentry->d_parent), name, |
2892 | tclass: inode_mode_to_security_class(mode), |
2893 | new_isid: &newsid); |
2894 | if (rc) |
2895 | return rc; |
2896 | |
2897 | tsec = selinux_cred(new); |
2898 | tsec->create_sid = newsid; |
2899 | return 0; |
2900 | } |
2901 | |
2902 | static int selinux_inode_init_security(struct inode *inode, struct inode *dir, |
2903 | const struct qstr *qstr, |
2904 | struct xattr *xattrs, int *xattr_count) |
2905 | { |
2906 | const struct task_security_struct *tsec = selinux_cred(current_cred()); |
2907 | struct superblock_security_struct *sbsec; |
2908 | struct xattr *xattr = lsm_get_xattr_slot(xattrs, xattr_count); |
2909 | u32 newsid, clen; |
2910 | int rc; |
2911 | char *context; |
2912 | |
2913 | sbsec = selinux_superblock(dir->i_sb); |
2914 | |
2915 | newsid = tsec->create_sid; |
2916 | |
2917 | rc = selinux_determine_inode_label(tsec, dir, name: qstr, |
2918 | tclass: inode_mode_to_security_class(mode: inode->i_mode), |
2919 | new_isid: &newsid); |
2920 | if (rc) |
2921 | return rc; |
2922 | |
2923 | /* Possibly defer initialization to selinux_complete_init. */ |
2924 | if (sbsec->flags & SE_SBINITIALIZED) { |
2925 | struct inode_security_struct *isec = selinux_inode(inode); |
2926 | isec->sclass = inode_mode_to_security_class(mode: inode->i_mode); |
2927 | isec->sid = newsid; |
2928 | isec->initialized = LABEL_INITIALIZED; |
2929 | } |
2930 | |
2931 | if (!selinux_initialized() || |
2932 | !(sbsec->flags & SBLABEL_MNT)) |
2933 | return -EOPNOTSUPP; |
2934 | |
2935 | if (xattr) { |
2936 | rc = security_sid_to_context_force(newsid, |
2937 | &context, &clen); |
2938 | if (rc) |
2939 | return rc; |
2940 | xattr->value = context; |
2941 | xattr->value_len = clen; |
2942 | xattr->name = XATTR_SELINUX_SUFFIX; |
2943 | } |
2944 | |
2945 | return 0; |
2946 | } |
2947 | |
2948 | static int selinux_inode_init_security_anon(struct inode *inode, |
2949 | const struct qstr *name, |
2950 | const struct inode *context_inode) |
2951 | { |
2952 | const struct task_security_struct *tsec = selinux_cred(current_cred()); |
2953 | struct common_audit_data ad; |
2954 | struct inode_security_struct *isec; |
2955 | int rc; |
2956 | |
2957 | if (unlikely(!selinux_initialized())) |
2958 | return 0; |
2959 | |
2960 | isec = selinux_inode(inode); |
2961 | |
2962 | /* |
2963 | * We only get here once per ephemeral inode. The inode has |
2964 | * been initialized via inode_alloc_security but is otherwise |
2965 | * untouched. |
2966 | */ |
2967 | |
2968 | if (context_inode) { |
2969 | struct inode_security_struct *context_isec = |
2970 | selinux_inode(context_inode); |
2971 | if (context_isec->initialized != LABEL_INITIALIZED) { |
2972 | pr_err("SELinux: context_inode is not initialized\n" ); |
2973 | return -EACCES; |
2974 | } |
2975 | |
2976 | isec->sclass = context_isec->sclass; |
2977 | isec->sid = context_isec->sid; |
2978 | } else { |
2979 | isec->sclass = SECCLASS_ANON_INODE; |
2980 | rc = security_transition_sid( |
2981 | tsec->sid, tsec->sid, |
2982 | isec->sclass, name, &isec->sid); |
2983 | if (rc) |
2984 | return rc; |
2985 | } |
2986 | |
2987 | isec->initialized = LABEL_INITIALIZED; |
2988 | /* |
2989 | * Now that we've initialized security, check whether we're |
2990 | * allowed to actually create this type of anonymous inode. |
2991 | */ |
2992 | |
2993 | ad.type = LSM_AUDIT_DATA_ANONINODE; |
2994 | ad.u.anonclass = name ? (const char *)name->name : "?" ; |
2995 | |
2996 | return avc_has_perm(tsec->sid, |
2997 | isec->sid, |
2998 | isec->sclass, |
2999 | FILE__CREATE, |
3000 | &ad); |
3001 | } |
3002 | |
3003 | static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode) |
3004 | { |
3005 | return may_create(dir, dentry, SECCLASS_FILE); |
3006 | } |
3007 | |
3008 | static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry) |
3009 | { |
3010 | return may_link(dir, dentry: old_dentry, MAY_LINK); |
3011 | } |
3012 | |
3013 | static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry) |
3014 | { |
3015 | return may_link(dir, dentry, MAY_UNLINK); |
3016 | } |
3017 | |
3018 | static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name) |
3019 | { |
3020 | return may_create(dir, dentry, SECCLASS_LNK_FILE); |
3021 | } |
3022 | |
3023 | static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask) |
3024 | { |
3025 | return may_create(dir, dentry, SECCLASS_DIR); |
3026 | } |
3027 | |
3028 | static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry) |
3029 | { |
3030 | return may_link(dir, dentry, MAY_RMDIR); |
3031 | } |
3032 | |
3033 | static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev) |
3034 | { |
3035 | return may_create(dir, dentry, tclass: inode_mode_to_security_class(mode)); |
3036 | } |
3037 | |
3038 | static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry, |
3039 | struct inode *new_inode, struct dentry *new_dentry) |
3040 | { |
3041 | return may_rename(old_dir: old_inode, old_dentry, new_dir: new_inode, new_dentry); |
3042 | } |
3043 | |
3044 | static int selinux_inode_readlink(struct dentry *dentry) |
3045 | { |
3046 | const struct cred *cred = current_cred(); |
3047 | |
3048 | return dentry_has_perm(cred, dentry, FILE__READ); |
3049 | } |
3050 | |
3051 | static int selinux_inode_follow_link(struct dentry *dentry, struct inode *inode, |
3052 | bool rcu) |
3053 | { |
3054 | const struct cred *cred = current_cred(); |
3055 | struct common_audit_data ad; |
3056 | struct inode_security_struct *isec; |
3057 | u32 sid; |
3058 | |
3059 | validate_creds(cred); |
3060 | |
3061 | ad.type = LSM_AUDIT_DATA_DENTRY; |
3062 | ad.u.dentry = dentry; |
3063 | sid = cred_sid(cred); |
3064 | isec = inode_security_rcu(inode, rcu); |
3065 | if (IS_ERR(ptr: isec)) |
3066 | return PTR_ERR(ptr: isec); |
3067 | |
3068 | return avc_has_perm(sid, isec->sid, isec->sclass, FILE__READ, &ad); |
3069 | } |
3070 | |
3071 | static noinline int audit_inode_permission(struct inode *inode, |
3072 | u32 perms, u32 audited, u32 denied, |
3073 | int result) |
3074 | { |
3075 | struct common_audit_data ad; |
3076 | struct inode_security_struct *isec = selinux_inode(inode); |
3077 | |
3078 | ad.type = LSM_AUDIT_DATA_INODE; |
3079 | ad.u.inode = inode; |
3080 | |
3081 | return slow_avc_audit(current_sid(), isec->sid, isec->sclass, perms, |
3082 | audited, denied, result, &ad); |
3083 | } |
3084 | |
3085 | static int selinux_inode_permission(struct inode *inode, int mask) |
3086 | { |
3087 | const struct cred *cred = current_cred(); |
3088 | u32 perms; |
3089 | bool from_access; |
3090 | bool no_block = mask & MAY_NOT_BLOCK; |
3091 | struct inode_security_struct *isec; |
3092 | u32 sid; |
3093 | struct av_decision avd; |
3094 | int rc, rc2; |
3095 | u32 audited, denied; |
3096 | |
3097 | from_access = mask & MAY_ACCESS; |
3098 | mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND); |
3099 | |
3100 | /* No permission to check. Existence test. */ |
3101 | if (!mask) |
3102 | return 0; |
3103 | |
3104 | validate_creds(cred); |
3105 | |
3106 | if (unlikely(IS_PRIVATE(inode))) |
3107 | return 0; |
3108 | |
3109 | perms = file_mask_to_av(mode: inode->i_mode, mask); |
3110 | |
3111 | sid = cred_sid(cred); |
3112 | isec = inode_security_rcu(inode, rcu: no_block); |
3113 | if (IS_ERR(ptr: isec)) |
3114 | return PTR_ERR(ptr: isec); |
3115 | |
3116 | rc = avc_has_perm_noaudit(sid, isec->sid, isec->sclass, perms, 0, |
3117 | &avd); |
3118 | audited = avc_audit_required(perms, &avd, rc, |
3119 | from_access ? FILE__AUDIT_ACCESS : 0, |
3120 | &denied); |
3121 | if (likely(!audited)) |
3122 | return rc; |
3123 | |
3124 | rc2 = audit_inode_permission(inode, perms, audited, denied, result: rc); |
3125 | if (rc2) |
3126 | return rc2; |
3127 | return rc; |
3128 | } |
3129 | |
3130 | static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr) |
3131 | { |
3132 | const struct cred *cred = current_cred(); |
3133 | struct inode *inode = d_backing_inode(upper: dentry); |
3134 | unsigned int ia_valid = iattr->ia_valid; |
3135 | __u32 av = FILE__WRITE; |
3136 | |
3137 | /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */ |
3138 | if (ia_valid & ATTR_FORCE) { |
3139 | ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE | |
3140 | ATTR_FORCE); |
3141 | if (!ia_valid) |
3142 | return 0; |
3143 | } |
3144 | |
3145 | if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID | |
3146 | ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET)) |
3147 | return dentry_has_perm(cred, dentry, FILE__SETATTR); |
3148 | |
3149 | if (selinux_policycap_openperm() && |
3150 | inode->i_sb->s_magic != SOCKFS_MAGIC && |
3151 | (ia_valid & ATTR_SIZE) && |
3152 | !(ia_valid & ATTR_FILE)) |
3153 | av |= FILE__OPEN; |
3154 | |
3155 | return dentry_has_perm(cred, dentry, av); |
3156 | } |
3157 | |
3158 | static int selinux_inode_getattr(const struct path *path) |
3159 | { |
3160 | return path_has_perm(current_cred(), path, FILE__GETATTR); |
3161 | } |
3162 | |
3163 | static bool has_cap_mac_admin(bool audit) |
3164 | { |
3165 | const struct cred *cred = current_cred(); |
3166 | unsigned int opts = audit ? CAP_OPT_NONE : CAP_OPT_NOAUDIT; |
3167 | |
3168 | if (cap_capable(cred, ns: &init_user_ns, CAP_MAC_ADMIN, opts)) |
3169 | return false; |
3170 | if (cred_has_capability(cred, CAP_MAC_ADMIN, opts, initns: true)) |
3171 | return false; |
3172 | return true; |
3173 | } |
3174 | |
3175 | static int selinux_inode_setxattr(struct mnt_idmap *idmap, |
3176 | struct dentry *dentry, const char *name, |
3177 | const void *value, size_t size, int flags) |
3178 | { |
3179 | struct inode *inode = d_backing_inode(upper: dentry); |
3180 | struct inode_security_struct *isec; |
3181 | struct superblock_security_struct *sbsec; |
3182 | struct common_audit_data ad; |
3183 | u32 newsid, sid = current_sid(); |
3184 | int rc = 0; |
3185 | |
3186 | if (strcmp(name, XATTR_NAME_SELINUX)) { |
3187 | rc = cap_inode_setxattr(dentry, name, value, size, flags); |
3188 | if (rc) |
3189 | return rc; |
3190 | |
3191 | /* Not an attribute we recognize, so just check the |
3192 | ordinary setattr permission. */ |
3193 | return dentry_has_perm(current_cred(), dentry, FILE__SETATTR); |
3194 | } |
3195 | |
3196 | if (!selinux_initialized()) |
3197 | return (inode_owner_or_capable(idmap, inode) ? 0 : -EPERM); |
3198 | |
3199 | sbsec = selinux_superblock(inode->i_sb); |
3200 | if (!(sbsec->flags & SBLABEL_MNT)) |
3201 | return -EOPNOTSUPP; |
3202 | |
3203 | if (!inode_owner_or_capable(idmap, inode)) |
3204 | return -EPERM; |
3205 | |
3206 | ad.type = LSM_AUDIT_DATA_DENTRY; |
3207 | ad.u.dentry = dentry; |
3208 | |
3209 | isec = backing_inode_security(dentry); |
3210 | rc = avc_has_perm(sid, isec->sid, isec->sclass, |
3211 | FILE__RELABELFROM, &ad); |
3212 | if (rc) |
3213 | return rc; |
3214 | |
3215 | rc = security_context_to_sid(value, size, &newsid, |
3216 | GFP_KERNEL); |
3217 | if (rc == -EINVAL) { |
3218 | if (!has_cap_mac_admin(audit: true)) { |
3219 | struct audit_buffer *ab; |
3220 | size_t audit_size; |
3221 | |
3222 | /* We strip a nul only if it is at the end, otherwise the |
3223 | * context contains a nul and we should audit that */ |
3224 | if (value) { |
3225 | const char *str = value; |
3226 | |
3227 | if (str[size - 1] == '\0') |
3228 | audit_size = size - 1; |
3229 | else |
3230 | audit_size = size; |
3231 | } else { |
3232 | audit_size = 0; |
3233 | } |
3234 | ab = audit_log_start(ctx: audit_context(), |
3235 | GFP_ATOMIC, AUDIT_SELINUX_ERR); |
3236 | if (!ab) |
3237 | return rc; |
3238 | audit_log_format(ab, fmt: "op=setxattr invalid_context=" ); |
3239 | audit_log_n_untrustedstring(ab, string: value, n: audit_size); |
3240 | audit_log_end(ab); |
3241 | |
3242 | return rc; |
3243 | } |
3244 | rc = security_context_to_sid_force(value, |
3245 | size, &newsid); |
3246 | } |
3247 | if (rc) |
3248 | return rc; |
3249 | |
3250 | rc = avc_has_perm(sid, newsid, isec->sclass, |
3251 | FILE__RELABELTO, &ad); |
3252 | if (rc) |
3253 | return rc; |
3254 | |
3255 | rc = security_validate_transition(isec->sid, newsid, |
3256 | sid, isec->sclass); |
3257 | if (rc) |
3258 | return rc; |
3259 | |
3260 | return avc_has_perm(newsid, |
3261 | sbsec->sid, |
3262 | SECCLASS_FILESYSTEM, |
3263 | FILESYSTEM__ASSOCIATE, |
3264 | &ad); |
3265 | } |
3266 | |
3267 | static int selinux_inode_set_acl(struct mnt_idmap *idmap, |
3268 | struct dentry *dentry, const char *acl_name, |
3269 | struct posix_acl *kacl) |
3270 | { |
3271 | return dentry_has_perm(current_cred(), dentry, FILE__SETATTR); |
3272 | } |
3273 | |
3274 | static int selinux_inode_get_acl(struct mnt_idmap *idmap, |
3275 | struct dentry *dentry, const char *acl_name) |
3276 | { |
3277 | return dentry_has_perm(current_cred(), dentry, FILE__GETATTR); |
3278 | } |
3279 | |
3280 | static int selinux_inode_remove_acl(struct mnt_idmap *idmap, |
3281 | struct dentry *dentry, const char *acl_name) |
3282 | { |
3283 | return dentry_has_perm(current_cred(), dentry, FILE__SETATTR); |
3284 | } |
3285 | |
3286 | static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name, |
3287 | const void *value, size_t size, |
3288 | int flags) |
3289 | { |
3290 | struct inode *inode = d_backing_inode(upper: dentry); |
3291 | struct inode_security_struct *isec; |
3292 | u32 newsid; |
3293 | int rc; |
3294 | |
3295 | if (strcmp(name, XATTR_NAME_SELINUX)) { |
3296 | /* Not an attribute we recognize, so nothing to do. */ |
3297 | return; |
3298 | } |
3299 | |
3300 | if (!selinux_initialized()) { |
3301 | /* If we haven't even been initialized, then we can't validate |
3302 | * against a policy, so leave the label as invalid. It may |
3303 | * resolve to a valid label on the next revalidation try if |
3304 | * we've since initialized. |
3305 | */ |
3306 | return; |
3307 | } |
3308 | |
3309 | rc = security_context_to_sid_force(value, size, |
3310 | &newsid); |
3311 | if (rc) { |
3312 | pr_err("SELinux: unable to map context to SID" |
3313 | "for (%s, %lu), rc=%d\n" , |
3314 | inode->i_sb->s_id, inode->i_ino, -rc); |
3315 | return; |
3316 | } |
3317 | |
3318 | isec = backing_inode_security(dentry); |
3319 | spin_lock(lock: &isec->lock); |
3320 | isec->sclass = inode_mode_to_security_class(mode: inode->i_mode); |
3321 | isec->sid = newsid; |
3322 | isec->initialized = LABEL_INITIALIZED; |
3323 | spin_unlock(lock: &isec->lock); |
3324 | } |
3325 | |
3326 | static int selinux_inode_getxattr(struct dentry *dentry, const char *name) |
3327 | { |
3328 | const struct cred *cred = current_cred(); |
3329 | |
3330 | return dentry_has_perm(cred, dentry, FILE__GETATTR); |
3331 | } |
3332 | |
3333 | static int selinux_inode_listxattr(struct dentry *dentry) |
3334 | { |
3335 | const struct cred *cred = current_cred(); |
3336 | |
3337 | return dentry_has_perm(cred, dentry, FILE__GETATTR); |
3338 | } |
3339 | |
3340 | static int selinux_inode_removexattr(struct mnt_idmap *idmap, |
3341 | struct dentry *dentry, const char *name) |
3342 | { |
3343 | if (strcmp(name, XATTR_NAME_SELINUX)) { |
3344 | int rc = cap_inode_removexattr(idmap, dentry, name); |
3345 | if (rc) |
3346 | return rc; |
3347 | |
3348 | /* Not an attribute we recognize, so just check the |
3349 | ordinary setattr permission. */ |
3350 | return dentry_has_perm(current_cred(), dentry, FILE__SETATTR); |
3351 | } |
3352 | |
3353 | if (!selinux_initialized()) |
3354 | return 0; |
3355 | |
3356 | /* No one is allowed to remove a SELinux security label. |
3357 | You can change the label, but all data must be labeled. */ |
3358 | return -EACCES; |
3359 | } |
3360 | |
3361 | static int selinux_path_notify(const struct path *path, u64 mask, |
3362 | unsigned int obj_type) |
3363 | { |
3364 | int ret; |
3365 | u32 perm; |
3366 | |
3367 | struct common_audit_data ad; |
3368 | |
3369 | ad.type = LSM_AUDIT_DATA_PATH; |
3370 | ad.u.path = *path; |
3371 | |
3372 | /* |
3373 | * Set permission needed based on the type of mark being set. |
3374 | * Performs an additional check for sb watches. |
3375 | */ |
3376 | switch (obj_type) { |
3377 | case FSNOTIFY_OBJ_TYPE_VFSMOUNT: |
3378 | perm = FILE__WATCH_MOUNT; |
3379 | break; |
3380 | case FSNOTIFY_OBJ_TYPE_SB: |
3381 | perm = FILE__WATCH_SB; |
3382 | ret = superblock_has_perm(current_cred(), path->dentry->d_sb, |
3383 | FILESYSTEM__WATCH, &ad); |
3384 | if (ret) |
3385 | return ret; |
3386 | break; |
3387 | case FSNOTIFY_OBJ_TYPE_INODE: |
3388 | perm = FILE__WATCH; |
3389 | break; |
3390 | default: |
3391 | return -EINVAL; |
3392 | } |
3393 | |
3394 | /* blocking watches require the file:watch_with_perm permission */ |
3395 | if (mask & (ALL_FSNOTIFY_PERM_EVENTS)) |
3396 | perm |= FILE__WATCH_WITH_PERM; |
3397 | |
3398 | /* watches on read-like events need the file:watch_reads permission */ |
3399 | if (mask & (FS_ACCESS | FS_ACCESS_PERM | FS_CLOSE_NOWRITE)) |
3400 | perm |= FILE__WATCH_READS; |
3401 | |
3402 | return path_has_perm(current_cred(), path, av: perm); |
3403 | } |
3404 | |
3405 | /* |
3406 | * Copy the inode security context value to the user. |
3407 | * |
3408 | * Permission check is handled by selinux_inode_getxattr hook. |
3409 | */ |
3410 | static int selinux_inode_getsecurity(struct mnt_idmap *idmap, |
3411 | struct inode *inode, const char *name, |
3412 | void **buffer, bool alloc) |
3413 | { |
3414 | u32 size; |
3415 | int error; |
3416 | char *context = NULL; |
3417 | struct inode_security_struct *isec; |
3418 | |
3419 | /* |
3420 | * If we're not initialized yet, then we can't validate contexts, so |
3421 | * just let vfs_getxattr fall back to using the on-disk xattr. |
3422 | */ |
3423 | if (!selinux_initialized() || |
3424 | strcmp(name, XATTR_SELINUX_SUFFIX)) |
3425 | return -EOPNOTSUPP; |
3426 | |
3427 | /* |
3428 | * If the caller has CAP_MAC_ADMIN, then get the raw context |
3429 | * value even if it is not defined by current policy; otherwise, |
3430 | * use the in-core value under current policy. |
3431 | * Use the non-auditing forms of the permission checks since |
3432 | * getxattr may be called by unprivileged processes commonly |
3433 | * and lack of permission just means that we fall back to the |
3434 | * in-core context value, not a denial. |
3435 | */ |
3436 | isec = inode_security(inode); |
3437 | if (has_cap_mac_admin(audit: false)) |
3438 | error = security_sid_to_context_force(isec->sid, &context, |
3439 | &size); |
3440 | else |
3441 | error = security_sid_to_context(isec->sid, |
3442 | &context, &size); |
3443 | if (error) |
3444 | return error; |
3445 | error = size; |
3446 | if (alloc) { |
3447 | *buffer = context; |
3448 | goto out_nofree; |
3449 | } |
3450 | kfree(objp: context); |
3451 | out_nofree: |
3452 | return error; |
3453 | } |
3454 | |
3455 | static int selinux_inode_setsecurity(struct inode *inode, const char *name, |
3456 | const void *value, size_t size, int flags) |
3457 | { |
3458 | struct inode_security_struct *isec = inode_security_novalidate(inode); |
3459 | struct superblock_security_struct *sbsec; |
3460 | u32 newsid; |
3461 | int rc; |
3462 | |
3463 | if (strcmp(name, XATTR_SELINUX_SUFFIX)) |
3464 | return -EOPNOTSUPP; |
3465 | |
3466 | sbsec = selinux_superblock(inode->i_sb); |
3467 | if (!(sbsec->flags & SBLABEL_MNT)) |
3468 | return -EOPNOTSUPP; |
3469 | |
3470 | if (!value || !size) |
3471 | return -EACCES; |
3472 | |
3473 | rc = security_context_to_sid(value, size, &newsid, |
3474 | GFP_KERNEL); |
3475 | if (rc) |
3476 | return rc; |
3477 | |
3478 | spin_lock(lock: &isec->lock); |
3479 | isec->sclass = inode_mode_to_security_class(mode: inode->i_mode); |
3480 | isec->sid = newsid; |
3481 | isec->initialized = LABEL_INITIALIZED; |
3482 | spin_unlock(lock: &isec->lock); |
3483 | return 0; |
3484 | } |
3485 | |
3486 | static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size) |
3487 | { |
3488 | const int len = sizeof(XATTR_NAME_SELINUX); |
3489 | |
3490 | if (!selinux_initialized()) |
3491 | return 0; |
3492 | |
3493 | if (buffer && len <= buffer_size) |
3494 | memcpy(buffer, XATTR_NAME_SELINUX, len); |
3495 | return len; |
3496 | } |
3497 | |
3498 | static void selinux_inode_getsecid(struct inode *inode, u32 *secid) |
3499 | { |
3500 | struct inode_security_struct *isec = inode_security_novalidate(inode); |
3501 | *secid = isec->sid; |
3502 | } |
3503 | |
3504 | static int selinux_inode_copy_up(struct dentry *src, struct cred **new) |
3505 | { |
3506 | u32 sid; |
3507 | struct task_security_struct *tsec; |
3508 | struct cred *new_creds = *new; |
3509 | |
3510 | if (new_creds == NULL) { |
3511 | new_creds = prepare_creds(); |
3512 | if (!new_creds) |
3513 | return -ENOMEM; |
3514 | } |
3515 | |
3516 | tsec = selinux_cred(new_creds); |
3517 | /* Get label from overlay inode and set it in create_sid */ |
3518 | selinux_inode_getsecid(inode: d_inode(dentry: src), secid: &sid); |
3519 | tsec->create_sid = sid; |
3520 | *new = new_creds; |
3521 | return 0; |
3522 | } |
3523 | |
3524 | static int selinux_inode_copy_up_xattr(const char *name) |
3525 | { |
3526 | /* The copy_up hook above sets the initial context on an inode, but we |
3527 | * don't then want to overwrite it by blindly copying all the lower |
3528 | * xattrs up. Instead, we have to filter out SELinux-related xattrs. |
3529 | */ |
3530 | if (strcmp(name, XATTR_NAME_SELINUX) == 0) |
3531 | return 1; /* Discard */ |
3532 | /* |
3533 | * Any other attribute apart from SELINUX is not claimed, supported |
3534 | * by selinux. |
3535 | */ |
3536 | return -EOPNOTSUPP; |
3537 | } |
3538 | |
3539 | /* kernfs node operations */ |
3540 | |
3541 | static int selinux_kernfs_init_security(struct kernfs_node *kn_dir, |
3542 | struct kernfs_node *kn) |
3543 | { |
3544 | const struct task_security_struct *tsec = selinux_cred(current_cred()); |
3545 | u32 parent_sid, newsid, clen; |
3546 | int rc; |
3547 | char *context; |
3548 | |
3549 | rc = kernfs_xattr_get(kn: kn_dir, XATTR_NAME_SELINUX, NULL, size: 0); |
3550 | if (rc == -ENODATA) |
3551 | return 0; |
3552 | else if (rc < 0) |
3553 | return rc; |
3554 | |
3555 | clen = (u32)rc; |
3556 | context = kmalloc(size: clen, GFP_KERNEL); |
3557 | if (!context) |
3558 | return -ENOMEM; |
3559 | |
3560 | rc = kernfs_xattr_get(kn: kn_dir, XATTR_NAME_SELINUX, value: context, size: clen); |
3561 | if (rc < 0) { |
3562 | kfree(objp: context); |
3563 | return rc; |
3564 | } |
3565 | |
3566 | rc = security_context_to_sid(context, clen, &parent_sid, |
3567 | GFP_KERNEL); |
3568 | kfree(objp: context); |
3569 | if (rc) |
3570 | return rc; |
3571 | |
3572 | if (tsec->create_sid) { |
3573 | newsid = tsec->create_sid; |
3574 | } else { |
3575 | u16 secclass = inode_mode_to_security_class(mode: kn->mode); |
3576 | struct qstr q; |
3577 | |
3578 | q.name = kn->name; |
3579 | q.hash_len = hashlen_string(salt: kn_dir, name: kn->name); |
3580 | |
3581 | rc = security_transition_sid(tsec->sid, |
3582 | parent_sid, secclass, &q, |
3583 | &newsid); |
3584 | if (rc) |
3585 | return rc; |
3586 | } |
3587 | |
3588 | rc = security_sid_to_context_force(newsid, |
3589 | &context, &clen); |
3590 | if (rc) |
3591 | return rc; |
3592 | |
3593 | rc = kernfs_xattr_set(kn, XATTR_NAME_SELINUX, value: context, size: clen, |
3594 | XATTR_CREATE); |
3595 | kfree(objp: context); |
3596 | return rc; |
3597 | } |
3598 | |
3599 | |
3600 | /* file security operations */ |
3601 | |
3602 | static int selinux_revalidate_file_permission(struct file *file, int mask) |
3603 | { |
3604 | const struct cred *cred = current_cred(); |
3605 | struct inode *inode = file_inode(f: file); |
3606 | |
3607 | /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */ |
3608 | if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE)) |
3609 | mask |= MAY_APPEND; |
3610 | |
3611 | return file_has_perm(cred, file, |
3612 | av: file_mask_to_av(mode: inode->i_mode, mask)); |
3613 | } |
3614 | |
3615 | static int selinux_file_permission(struct file *file, int mask) |
3616 | { |
3617 | struct inode *inode = file_inode(f: file); |
3618 | struct file_security_struct *fsec = selinux_file(file); |
3619 | struct inode_security_struct *isec; |
3620 | u32 sid = current_sid(); |
3621 | |
3622 | if (!mask) |
3623 | /* No permission to check. Existence test. */ |
3624 | return 0; |
3625 | |
3626 | isec = inode_security(inode); |
3627 | if (sid == fsec->sid && fsec->isid == isec->sid && |
3628 | fsec->pseqno == avc_policy_seqno()) |
3629 | /* No change since file_open check. */ |
3630 | return 0; |
3631 | |
3632 | return selinux_revalidate_file_permission(file, mask); |
3633 | } |
3634 | |
3635 | static int selinux_file_alloc_security(struct file *file) |
3636 | { |
3637 | struct file_security_struct *fsec = selinux_file(file); |
3638 | u32 sid = current_sid(); |
3639 | |
3640 | fsec->sid = sid; |
3641 | fsec->fown_sid = sid; |
3642 | |
3643 | return 0; |
3644 | } |
3645 | |
3646 | /* |
3647 | * Check whether a task has the ioctl permission and cmd |
3648 | * operation to an inode. |
3649 | */ |
3650 | static int ioctl_has_perm(const struct cred *cred, struct file *file, |
3651 | u32 requested, u16 cmd) |
3652 | { |
3653 | struct common_audit_data ad; |
3654 | struct file_security_struct *fsec = selinux_file(file); |
3655 | struct inode *inode = file_inode(f: file); |
3656 | struct inode_security_struct *isec; |
3657 | struct lsm_ioctlop_audit ioctl; |
3658 | u32 ssid = cred_sid(cred); |
3659 | int rc; |
3660 | u8 driver = cmd >> 8; |
3661 | u8 xperm = cmd & 0xff; |
3662 | |
3663 | ad.type = LSM_AUDIT_DATA_IOCTL_OP; |
3664 | ad.u.op = &ioctl; |
3665 | ad.u.op->cmd = cmd; |
3666 | ad.u.op->path = file->f_path; |
3667 | |
3668 | if (ssid != fsec->sid) { |
3669 | rc = avc_has_perm(ssid, fsec->sid, |
3670 | SECCLASS_FD, |
3671 | FD__USE, |
3672 | &ad); |
3673 | if (rc) |
3674 | goto out; |
3675 | } |
3676 | |
3677 | if (unlikely(IS_PRIVATE(inode))) |
3678 | return 0; |
3679 | |
3680 | isec = inode_security(inode); |
3681 | rc = avc_has_extended_perms(ssid, isec->sid, isec->sclass, |
3682 | requested, driver, xperm, &ad); |
3683 | out: |
3684 | return rc; |
3685 | } |
3686 | |
3687 | static int selinux_file_ioctl(struct file *file, unsigned int cmd, |
3688 | unsigned long arg) |
3689 | { |
3690 | const struct cred *cred = current_cred(); |
3691 | int error = 0; |
3692 | |
3693 | switch (cmd) { |
3694 | case FIONREAD: |
3695 | case FIBMAP: |
3696 | case FIGETBSZ: |
3697 | case FS_IOC_GETFLAGS: |
3698 | case FS_IOC_GETVERSION: |
3699 | error = file_has_perm(cred, file, FILE__GETATTR); |
3700 | break; |
3701 | |
3702 | case FS_IOC_SETFLAGS: |
3703 | case FS_IOC_SETVERSION: |
3704 | error = file_has_perm(cred, file, FILE__SETATTR); |
3705 | break; |
3706 | |
3707 | /* sys_ioctl() checks */ |
3708 | case FIONBIO: |
3709 | case FIOASYNC: |
3710 | error = file_has_perm(cred, file, av: 0); |
3711 | break; |
3712 | |
3713 | case KDSKBENT: |
3714 | case KDSKBSENT: |
3715 | error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG, |
3716 | CAP_OPT_NONE, initns: true); |
3717 | break; |
3718 | |
3719 | case FIOCLEX: |
3720 | case FIONCLEX: |
3721 | if (!selinux_policycap_ioctl_skip_cloexec()) |
3722 | error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd); |
3723 | break; |
3724 | |
3725 | /* default case assumes that the command will go |
3726 | * to the file's ioctl() function. |
3727 | */ |
3728 | default: |
3729 | error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd); |
3730 | } |
3731 | return error; |
3732 | } |
3733 | |
3734 | static int default_noexec __ro_after_init; |
3735 | |
3736 | static int file_map_prot_check(struct file *file, unsigned long prot, int shared) |
3737 | { |
3738 | const struct cred *cred = current_cred(); |
3739 | u32 sid = cred_sid(cred); |
3740 | int rc = 0; |
3741 | |
3742 | if (default_noexec && |
3743 | (prot & PROT_EXEC) && (!file || IS_PRIVATE(file_inode(file)) || |
3744 | (!shared && (prot & PROT_WRITE)))) { |
3745 | /* |
3746 | * We are making executable an anonymous mapping or a |
3747 | * private file mapping that will also be writable. |
3748 | * This has an additional check. |
3749 | */ |
3750 | rc = avc_has_perm(sid, sid, SECCLASS_PROCESS, |
3751 | PROCESS__EXECMEM, NULL); |
3752 | if (rc) |
3753 | goto error; |
3754 | } |
3755 | |
3756 | if (file) { |
3757 | /* read access is always possible with a mapping */ |
3758 | u32 av = FILE__READ; |
3759 | |
3760 | /* write access only matters if the mapping is shared */ |
3761 | if (shared && (prot & PROT_WRITE)) |
3762 | av |= FILE__WRITE; |
3763 | |
3764 | if (prot & PROT_EXEC) |
3765 | av |= FILE__EXECUTE; |
3766 | |
3767 | return file_has_perm(cred, file, av); |
3768 | } |
3769 | |
3770 | error: |
3771 | return rc; |
3772 | } |
3773 | |
3774 | static int selinux_mmap_addr(unsigned long addr) |
3775 | { |
3776 | int rc = 0; |
3777 | |
3778 | if (addr < CONFIG_LSM_MMAP_MIN_ADDR) { |
3779 | u32 sid = current_sid(); |
3780 | rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT, |
3781 | MEMPROTECT__MMAP_ZERO, NULL); |
3782 | } |
3783 | |
3784 | return rc; |
3785 | } |
3786 | |
3787 | static int selinux_mmap_file(struct file *file, |
3788 | unsigned long reqprot __always_unused, |
3789 | unsigned long prot, unsigned long flags) |
3790 | { |
3791 | struct common_audit_data ad; |
3792 | int rc; |
3793 | |
3794 | if (file) { |
3795 | ad.type = LSM_AUDIT_DATA_FILE; |
3796 | ad.u.file = file; |
3797 | rc = inode_has_perm(current_cred(), file_inode(file), |
3798 | FILE__MAP, &ad); |
3799 | if (rc) |
3800 | return rc; |
3801 | } |
3802 | |
3803 | return file_map_prot_check(file, prot, |
3804 | shared: (flags & MAP_TYPE) == MAP_SHARED); |
3805 | } |
3806 | |
3807 | static int selinux_file_mprotect(struct vm_area_struct *vma, |
3808 | unsigned long reqprot __always_unused, |
3809 | unsigned long prot) |
3810 | { |
3811 | const struct cred *cred = current_cred(); |
3812 | u32 sid = cred_sid(cred); |
3813 | |
3814 | if (default_noexec && |
3815 | (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) { |
3816 | int rc = 0; |
3817 | if (vma_is_initial_heap(vma)) { |
3818 | rc = avc_has_perm(sid, sid, SECCLASS_PROCESS, |
3819 | PROCESS__EXECHEAP, NULL); |
3820 | } else if (!vma->vm_file && (vma_is_initial_stack(vma) || |
3821 | vma_is_stack_for_current(vma))) { |
3822 | rc = avc_has_perm(sid, sid, SECCLASS_PROCESS, |
3823 | PROCESS__EXECSTACK, NULL); |
3824 | } else if (vma->vm_file && vma->anon_vma) { |
3825 | /* |
3826 | * We are making executable a file mapping that has |
3827 | * had some COW done. Since pages might have been |
3828 | * written, check ability to execute the possibly |
3829 | * modified content. This typically should only |
3830 | * occur for text relocations. |
3831 | */ |
3832 | rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD); |
3833 | } |
3834 | if (rc) |
3835 | return rc; |
3836 | } |
3837 | |
3838 | return file_map_prot_check(file: vma->vm_file, prot, shared: vma->vm_flags&VM_SHARED); |
3839 | } |
3840 | |
3841 | static int selinux_file_lock(struct file *file, unsigned int cmd) |
3842 | { |
3843 | const struct cred *cred = current_cred(); |
3844 | |
3845 | return file_has_perm(cred, file, FILE__LOCK); |
3846 | } |
3847 | |
3848 | static int selinux_file_fcntl(struct file *file, unsigned int cmd, |
3849 | unsigned long arg) |
3850 | { |
3851 | const struct cred *cred = current_cred(); |
3852 | int err = 0; |
3853 | |
3854 | switch (cmd) { |
3855 | case F_SETFL: |
3856 | if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) { |
3857 | err = file_has_perm(cred, file, FILE__WRITE); |
3858 | break; |
3859 | } |
3860 | fallthrough; |
3861 | case F_SETOWN: |
3862 | case F_SETSIG: |
3863 | case F_GETFL: |
3864 | case F_GETOWN: |
3865 | case F_GETSIG: |
3866 | case F_GETOWNER_UIDS: |
3867 | /* Just check FD__USE permission */ |
3868 | err = file_has_perm(cred, file, av: 0); |
3869 | break; |
3870 | case F_GETLK: |
3871 | case F_SETLK: |
3872 | case F_SETLKW: |
3873 | case F_OFD_GETLK: |
3874 | case F_OFD_SETLK: |
3875 | case F_OFD_SETLKW: |
3876 | #if BITS_PER_LONG == 32 |
3877 | case F_GETLK64: |
3878 | case F_SETLK64: |
3879 | case F_SETLKW64: |
3880 | #endif |
3881 | err = file_has_perm(cred, file, FILE__LOCK); |
3882 | break; |
3883 | } |
3884 | |
3885 | return err; |
3886 | } |
3887 | |
3888 | static void selinux_file_set_fowner(struct file *file) |
3889 | { |
3890 | struct file_security_struct *fsec; |
3891 | |
3892 | fsec = selinux_file(file); |
3893 | fsec->fown_sid = current_sid(); |
3894 | } |
3895 | |
3896 | static int selinux_file_send_sigiotask(struct task_struct *tsk, |
3897 | struct fown_struct *fown, int signum) |
3898 | { |
3899 | struct file *file; |
3900 | u32 sid = task_sid_obj(task: tsk); |
3901 | u32 perm; |
3902 | struct file_security_struct *fsec; |
3903 | |
3904 | /* struct fown_struct is never outside the context of a struct file */ |
3905 | file = container_of(fown, struct file, f_owner); |
3906 | |
3907 | fsec = selinux_file(file); |
3908 | |
3909 | if (!signum) |
3910 | perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */ |
3911 | else |
3912 | perm = signal_to_av(sig: signum); |
3913 | |
3914 | return avc_has_perm(fsec->fown_sid, sid, |
3915 | SECCLASS_PROCESS, perm, NULL); |
3916 | } |
3917 | |
3918 | static int selinux_file_receive(struct file *file) |
3919 | { |
3920 | const struct cred *cred = current_cred(); |
3921 | |
3922 | return file_has_perm(cred, file, av: file_to_av(file)); |
3923 | } |
3924 | |
3925 | static int selinux_file_open(struct file *file) |
3926 | { |
3927 | struct file_security_struct *fsec; |
3928 | struct inode_security_struct *isec; |
3929 | |
3930 | fsec = selinux_file(file); |
3931 | isec = inode_security(inode: file_inode(f: file)); |
3932 | /* |
3933 | * Save inode label and policy sequence number |
3934 | * at open-time so that selinux_file_permission |
3935 | * can determine whether revalidation is necessary. |
3936 | * Task label is already saved in the file security |
3937 | * struct as its SID. |
3938 | */ |
3939 | fsec->isid = isec->sid; |
3940 | fsec->pseqno = avc_policy_seqno(); |
3941 | /* |
3942 | * Since the inode label or policy seqno may have changed |
3943 | * between the selinux_inode_permission check and the saving |
3944 | * of state above, recheck that access is still permitted. |
3945 | * Otherwise, access might never be revalidated against the |
3946 | * new inode label or new policy. |
3947 | * This check is not redundant - do not remove. |
3948 | */ |
3949 | return file_path_has_perm(cred: file->f_cred, file, av: open_file_to_av(file)); |
3950 | } |
3951 | |
3952 | /* task security operations */ |
3953 | |
3954 | static int selinux_task_alloc(struct task_struct *task, |
3955 | unsigned long clone_flags) |
3956 | { |
3957 | u32 sid = current_sid(); |
3958 | |
3959 | return avc_has_perm(sid, sid, SECCLASS_PROCESS, PROCESS__FORK, NULL); |
3960 | } |
3961 | |
3962 | /* |
3963 | * prepare a new set of credentials for modification |
3964 | */ |
3965 | static int selinux_cred_prepare(struct cred *new, const struct cred *old, |
3966 | gfp_t gfp) |
3967 | { |
3968 | const struct task_security_struct *old_tsec = selinux_cred(old); |
3969 | struct task_security_struct *tsec = selinux_cred(new); |
3970 | |
3971 | *tsec = *old_tsec; |
3972 | return 0; |
3973 | } |
3974 | |
3975 | /* |
3976 | * transfer the SELinux data to a blank set of creds |
3977 | */ |
3978 | static void selinux_cred_transfer(struct cred *new, const struct cred *old) |
3979 | { |
3980 | const struct task_security_struct *old_tsec = selinux_cred(old); |
3981 | struct task_security_struct *tsec = selinux_cred(new); |
3982 | |
3983 | *tsec = *old_tsec; |
3984 | } |
3985 | |
3986 | static void selinux_cred_getsecid(const struct cred *c, u32 *secid) |
3987 | { |
3988 | *secid = cred_sid(cred: c); |
3989 | } |
3990 | |
3991 | /* |
3992 | * set the security data for a kernel service |
3993 | * - all the creation contexts are set to unlabelled |
3994 | */ |
3995 | static int selinux_kernel_act_as(struct cred *new, u32 secid) |
3996 | { |
3997 | struct task_security_struct *tsec = selinux_cred(new); |
3998 | u32 sid = current_sid(); |
3999 | int ret; |
4000 | |
4001 | ret = avc_has_perm(sid, secid, |
4002 | SECCLASS_KERNEL_SERVICE, |
4003 | KERNEL_SERVICE__USE_AS_OVERRIDE, |
4004 | NULL); |
4005 | if (ret == 0) { |
4006 | tsec->sid = secid; |
4007 | tsec->create_sid = 0; |
4008 | tsec->keycreate_sid = 0; |
4009 | tsec->sockcreate_sid = 0; |
4010 | } |
4011 | return ret; |
4012 | } |
4013 | |
4014 | /* |
4015 | * set the file creation context in a security record to the same as the |
4016 | * objective context of the specified inode |
4017 | */ |
4018 | static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode) |
4019 | { |
4020 | struct inode_security_struct *isec = inode_security(inode); |
4021 | struct task_security_struct *tsec = selinux_cred(new); |
4022 | u32 sid = current_sid(); |
4023 | int ret; |
4024 | |
4025 | ret = avc_has_perm(sid, isec->sid, |
4026 | SECCLASS_KERNEL_SERVICE, |
4027 | KERNEL_SERVICE__CREATE_FILES_AS, |
4028 | NULL); |
4029 | |
4030 | if (ret == 0) |
4031 | tsec->create_sid = isec->sid; |
4032 | return ret; |
4033 | } |
4034 | |
4035 | static int selinux_kernel_module_request(char *kmod_name) |
4036 | { |
4037 | struct common_audit_data ad; |
4038 | |
4039 | ad.type = LSM_AUDIT_DATA_KMOD; |
4040 | ad.u.kmod_name = kmod_name; |
4041 | |
4042 | return avc_has_perm(current_sid(), SECINITSID_KERNEL, SECCLASS_SYSTEM, |
4043 | SYSTEM__MODULE_REQUEST, &ad); |
4044 | } |
4045 | |
4046 | static int selinux_kernel_module_from_file(struct file *file) |
4047 | { |
4048 | struct common_audit_data ad; |
4049 | struct inode_security_struct *isec; |
4050 | struct file_security_struct *fsec; |
4051 | u32 sid = current_sid(); |
4052 | int rc; |
4053 | |
4054 | /* init_module */ |
4055 | if (file == NULL) |
4056 | return avc_has_perm(sid, sid, SECCLASS_SYSTEM, |
4057 | SYSTEM__MODULE_LOAD, NULL); |
4058 | |
4059 | /* finit_module */ |
4060 | |
4061 | ad.type = LSM_AUDIT_DATA_FILE; |
4062 | ad.u.file = file; |
4063 | |
4064 | fsec = selinux_file(file); |
4065 | if (sid != fsec->sid) { |
4066 | rc = avc_has_perm(sid, fsec->sid, SECCLASS_FD, FD__USE, &ad); |
4067 | if (rc) |
4068 | return rc; |
4069 | } |
4070 | |
4071 | isec = inode_security(inode: file_inode(f: file)); |
4072 | return avc_has_perm(sid, isec->sid, SECCLASS_SYSTEM, |
4073 | SYSTEM__MODULE_LOAD, &ad); |
4074 | } |
4075 | |
4076 | static int selinux_kernel_read_file(struct file *file, |
4077 | enum kernel_read_file_id id, |
4078 | bool contents) |
4079 | { |
4080 | int rc = 0; |
4081 | |
4082 | switch (id) { |
4083 | case READING_MODULE: |
4084 | rc = selinux_kernel_module_from_file(file: contents ? file : NULL); |
4085 | break; |
4086 | default: |
4087 | break; |
4088 | } |
4089 | |
4090 | return rc; |
4091 | } |
4092 | |
4093 | static int selinux_kernel_load_data(enum kernel_load_data_id id, bool contents) |
4094 | { |
4095 | int rc = 0; |
4096 | |
4097 | switch (id) { |
4098 | case LOADING_MODULE: |
4099 | rc = selinux_kernel_module_from_file(NULL); |
4100 | break; |
4101 | default: |
4102 | break; |
4103 | } |
4104 | |
4105 | return rc; |
4106 | } |
4107 | |
4108 | static int selinux_task_setpgid(struct task_struct *p, pid_t pgid) |
4109 | { |
4110 | return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, |
4111 | PROCESS__SETPGID, NULL); |
4112 | } |
4113 | |
4114 | static int selinux_task_getpgid(struct task_struct *p) |
4115 | { |
4116 | return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, |
4117 | PROCESS__GETPGID, NULL); |
4118 | } |
4119 | |
4120 | static int selinux_task_getsid(struct task_struct *p) |
4121 | { |
4122 | return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, |
4123 | PROCESS__GETSESSION, NULL); |
4124 | } |
4125 | |
4126 | static void selinux_current_getsecid_subj(u32 *secid) |
4127 | { |
4128 | *secid = current_sid(); |
4129 | } |
4130 | |
4131 | static void selinux_task_getsecid_obj(struct task_struct *p, u32 *secid) |
4132 | { |
4133 | *secid = task_sid_obj(task: p); |
4134 | } |
4135 | |
4136 | static int selinux_task_setnice(struct task_struct *p, int nice) |
4137 | { |
4138 | return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, |
4139 | PROCESS__SETSCHED, NULL); |
4140 | } |
4141 | |
4142 | static int selinux_task_setioprio(struct task_struct *p, int ioprio) |
4143 | { |
4144 | return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, |
4145 | PROCESS__SETSCHED, NULL); |
4146 | } |
4147 | |
4148 | static int selinux_task_getioprio(struct task_struct *p) |
4149 | { |
4150 | return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, |
4151 | PROCESS__GETSCHED, NULL); |
4152 | } |
4153 | |
4154 | static int selinux_task_prlimit(const struct cred *cred, const struct cred *tcred, |
4155 | unsigned int flags) |
4156 | { |
4157 | u32 av = 0; |
4158 | |
4159 | if (!flags) |
4160 | return 0; |
4161 | if (flags & LSM_PRLIMIT_WRITE) |
4162 | av |= PROCESS__SETRLIMIT; |
4163 | if (flags & LSM_PRLIMIT_READ) |
4164 | av |= PROCESS__GETRLIMIT; |
4165 | return avc_has_perm(cred_sid(cred), cred_sid(tcred), |
4166 | SECCLASS_PROCESS, av, NULL); |
4167 | } |
4168 | |
4169 | static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource, |
4170 | struct rlimit *new_rlim) |
4171 | { |
4172 | struct rlimit *old_rlim = p->signal->rlim + resource; |
4173 | |
4174 | /* Control the ability to change the hard limit (whether |
4175 | lowering or raising it), so that the hard limit can |
4176 | later be used as a safe reset point for the soft limit |
4177 | upon context transitions. See selinux_bprm_committing_creds. */ |
4178 | if (old_rlim->rlim_max != new_rlim->rlim_max) |
4179 | return avc_has_perm(current_sid(), task_sid_obj(p), |
4180 | SECCLASS_PROCESS, PROCESS__SETRLIMIT, NULL); |
4181 | |
4182 | return 0; |
4183 | } |
4184 | |
4185 | static int selinux_task_setscheduler(struct task_struct *p) |
4186 | { |
4187 | return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, |
4188 | PROCESS__SETSCHED, NULL); |
4189 | } |
4190 | |
4191 | static int selinux_task_getscheduler(struct task_struct *p) |
4192 | { |
4193 | return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, |
4194 | PROCESS__GETSCHED, NULL); |
4195 | } |
4196 | |
4197 | static int selinux_task_movememory(struct task_struct *p) |
4198 | { |
4199 | return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS, |
4200 | PROCESS__SETSCHED, NULL); |
4201 | } |
4202 | |
4203 | static int selinux_task_kill(struct task_struct *p, struct kernel_siginfo *info, |
4204 | int sig, const struct cred *cred) |
4205 | { |
4206 | u32 secid; |
4207 | u32 perm; |
4208 | |
4209 | if (!sig) |
4210 | perm = PROCESS__SIGNULL; /* null signal; existence test */ |
4211 | else |
4212 | perm = signal_to_av(sig); |
4213 | if (!cred) |
4214 | secid = current_sid(); |
4215 | else |
4216 | secid = cred_sid(cred); |
4217 | return avc_has_perm(secid, task_sid_obj(p), SECCLASS_PROCESS, perm, NULL); |
4218 | } |
4219 | |
4220 | static void selinux_task_to_inode(struct task_struct *p, |
4221 | struct inode *inode) |
4222 | { |
4223 | struct inode_security_struct *isec = selinux_inode(inode); |
4224 | u32 sid = task_sid_obj(task: p); |
4225 | |
4226 | spin_lock(lock: &isec->lock); |
4227 | isec->sclass = inode_mode_to_security_class(mode: inode->i_mode); |
4228 | isec->sid = sid; |
4229 | isec->initialized = LABEL_INITIALIZED; |
4230 | spin_unlock(lock: &isec->lock); |
4231 | } |
4232 | |
4233 | static int selinux_userns_create(const struct cred *cred) |
4234 | { |
4235 | u32 sid = current_sid(); |
4236 | |
4237 | return avc_has_perm(sid, sid, SECCLASS_USER_NAMESPACE, |
4238 | USER_NAMESPACE__CREATE, NULL); |
4239 | } |
4240 | |
4241 | /* Returns error only if unable to parse addresses */ |
4242 | static int selinux_parse_skb_ipv4(struct sk_buff *skb, |
4243 | struct common_audit_data *ad, u8 *proto) |
4244 | { |
4245 | int offset, ihlen, ret = -EINVAL; |
4246 | struct iphdr _iph, *ih; |
4247 | |
4248 | offset = skb_network_offset(skb); |
4249 | ih = skb_header_pointer(skb, offset, len: sizeof(_iph), buffer: &_iph); |
4250 | if (ih == NULL) |
4251 | goto out; |
4252 | |
4253 | ihlen = ih->ihl * 4; |
4254 | if (ihlen < sizeof(_iph)) |
4255 | goto out; |
4256 | |
4257 | ad->u.net->v4info.saddr = ih->saddr; |
4258 | ad->u.net->v4info.daddr = ih->daddr; |
4259 | ret = 0; |
4260 | |
4261 | if (proto) |
4262 | *proto = ih->protocol; |
4263 | |
4264 | switch (ih->protocol) { |
4265 | case IPPROTO_TCP: { |
4266 | struct tcphdr _tcph, *th; |
4267 | |
4268 | if (ntohs(ih->frag_off) & IP_OFFSET) |
4269 | break; |
4270 | |
4271 | offset += ihlen; |
4272 | th = skb_header_pointer(skb, offset, len: sizeof(_tcph), buffer: &_tcph); |
4273 | if (th == NULL) |
4274 | break; |
4275 | |
4276 | ad->u.net->sport = th->source; |
4277 | ad->u.net->dport = th->dest; |
4278 | break; |
4279 | } |
4280 | |
4281 | case IPPROTO_UDP: { |
4282 | struct udphdr _udph, *uh; |
4283 | |
4284 | if (ntohs(ih->frag_off) & IP_OFFSET) |
4285 | break; |
4286 | |
4287 | offset += ihlen; |
4288 | uh = skb_header_pointer(skb, offset, len: sizeof(_udph), buffer: &_udph); |
4289 | if (uh == NULL) |
4290 | break; |
4291 | |
4292 | ad->u.net->sport = uh->source; |
4293 | ad->u.net->dport = uh->dest; |
4294 | break; |
4295 | } |
4296 | |
4297 | case IPPROTO_DCCP: { |
4298 | struct dccp_hdr _dccph, *dh; |
4299 | |
4300 | if (ntohs(ih->frag_off) & IP_OFFSET) |
4301 | break; |
4302 | |
4303 | offset += ihlen; |
4304 | dh = skb_header_pointer(skb, offset, len: sizeof(_dccph), buffer: &_dccph); |
4305 | if (dh == NULL) |
4306 | break; |
4307 | |
4308 | ad->u.net->sport = dh->dccph_sport; |
4309 | ad->u.net->dport = dh->dccph_dport; |
4310 | break; |
4311 | } |
4312 | |
4313 | #if IS_ENABLED(CONFIG_IP_SCTP) |
4314 | case IPPROTO_SCTP: { |
4315 | struct sctphdr _sctph, *sh; |
4316 | |
4317 | if (ntohs(ih->frag_off) & IP_OFFSET) |
4318 | break; |
4319 | |
4320 | offset += ihlen; |
4321 | sh = skb_header_pointer(skb, offset, len: sizeof(_sctph), buffer: &_sctph); |
4322 | if (sh == NULL) |
4323 | break; |
4324 | |
4325 | ad->u.net->sport = sh->source; |
4326 | ad->u.net->dport = sh->dest; |
4327 | break; |
4328 | } |
4329 | #endif |
4330 | default: |
4331 | break; |
4332 | } |
4333 | out: |
4334 | return ret; |
4335 | } |
4336 | |
4337 | #if IS_ENABLED(CONFIG_IPV6) |
4338 | |
4339 | /* Returns error only if unable to parse addresses */ |
4340 | static int selinux_parse_skb_ipv6(struct sk_buff *skb, |
4341 | struct common_audit_data *ad, u8 *proto) |
4342 | { |
4343 | u8 nexthdr; |
4344 | int ret = -EINVAL, offset; |
4345 | struct ipv6hdr _ipv6h, *ip6; |
4346 | __be16 frag_off; |
4347 | |
4348 | offset = skb_network_offset(skb); |
4349 | ip6 = skb_header_pointer(skb, offset, len: sizeof(_ipv6h), buffer: &_ipv6h); |
4350 | if (ip6 == NULL) |
4351 | goto out; |
4352 | |
4353 | ad->u.net->v6info.saddr = ip6->saddr; |
4354 | ad->u.net->v6info.daddr = ip6->daddr; |
4355 | ret = 0; |
4356 | |
4357 | nexthdr = ip6->nexthdr; |
4358 | offset += sizeof(_ipv6h); |
4359 | offset = ipv6_skip_exthdr(skb, start: offset, nexthdrp: &nexthdr, frag_offp: &frag_off); |
4360 | if (offset < 0) |
4361 | goto out; |
4362 | |
4363 | if (proto) |
4364 | *proto = nexthdr; |
4365 | |
4366 | switch (nexthdr) { |
4367 | case IPPROTO_TCP: { |
4368 | struct tcphdr _tcph, *th; |
4369 | |
4370 | th = skb_header_pointer(skb, offset, len: sizeof(_tcph), buffer: &_tcph); |
4371 | if (th == NULL) |
4372 | break; |
4373 | |
4374 | ad->u.net->sport = th->source; |
4375 | ad->u.net->dport = th->dest; |
4376 | break; |
4377 | } |
4378 | |
4379 | case IPPROTO_UDP: { |
4380 | struct udphdr _udph, *uh; |
4381 | |
4382 | uh = skb_header_pointer(skb, offset, len: sizeof(_udph), buffer: &_udph); |
4383 | if (uh == NULL) |
4384 | break; |
4385 | |
4386 | ad->u.net->sport = uh->source; |
4387 | ad->u.net->dport = uh->dest; |
4388 | break; |
4389 | } |
4390 | |
4391 | case IPPROTO_DCCP: { |
4392 | struct dccp_hdr _dccph, *dh; |
4393 | |
4394 | dh = skb_header_pointer(skb, offset, len: sizeof(_dccph), buffer: &_dccph); |
4395 | if (dh == NULL) |
4396 | break; |
4397 | |
4398 | ad->u.net->sport = dh->dccph_sport; |
4399 | ad->u.net->dport = dh->dccph_dport; |
4400 | break; |
4401 | } |
4402 | |
4403 | #if IS_ENABLED(CONFIG_IP_SCTP) |
4404 | case IPPROTO_SCTP: { |
4405 | struct sctphdr _sctph, *sh; |
4406 | |
4407 | sh = skb_header_pointer(skb, offset, len: sizeof(_sctph), buffer: &_sctph); |
4408 | if (sh == NULL) |
4409 | break; |
4410 | |
4411 | ad->u.net->sport = sh->source; |
4412 | ad->u.net->dport = sh->dest; |
4413 | break; |
4414 | } |
4415 | #endif |
4416 | /* includes fragments */ |
4417 | default: |
4418 | break; |
4419 | } |
4420 | out: |
4421 | return ret; |
4422 | } |
4423 | |
4424 | #endif /* IPV6 */ |
4425 | |
4426 | static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad, |
4427 | char **_addrp, int src, u8 *proto) |
4428 | { |
4429 | char *addrp; |
4430 | int ret; |
4431 | |
4432 | switch (ad->u.net->family) { |
4433 | case PF_INET: |
4434 | ret = selinux_parse_skb_ipv4(skb, ad, proto); |
4435 | if (ret) |
4436 | goto parse_error; |
4437 | addrp = (char *)(src ? &ad->u.net->v4info.saddr : |
4438 | &ad->u.net->v4info.daddr); |
4439 | goto okay; |
4440 | |
4441 | #if IS_ENABLED(CONFIG_IPV6) |
4442 | case PF_INET6: |
4443 | ret = selinux_parse_skb_ipv6(skb, ad, proto); |
4444 | if (ret) |
4445 | goto parse_error; |
4446 | addrp = (char *)(src ? &ad->u.net->v6info.saddr : |
4447 | &ad->u.net->v6info.daddr); |
4448 | goto okay; |
4449 | #endif /* IPV6 */ |
4450 | default: |
4451 | addrp = NULL; |
4452 | goto okay; |
4453 | } |
4454 | |
4455 | parse_error: |
4456 | pr_warn( |
4457 | "SELinux: failure in selinux_parse_skb()," |
4458 | " unable to parse packet\n" ); |
4459 | return ret; |
4460 | |
4461 | okay: |
4462 | if (_addrp) |
4463 | *_addrp = addrp; |
4464 | return 0; |
4465 | } |
4466 | |
4467 | /** |
4468 | * selinux_skb_peerlbl_sid - Determine the peer label of a packet |
4469 | * @skb: the packet |
4470 | * @family: protocol family |
4471 | * @sid: the packet's peer label SID |
4472 | * |
4473 | * Description: |
4474 | * Check the various different forms of network peer labeling and determine |
4475 | * the peer label/SID for the packet; most of the magic actually occurs in |
4476 | * the security server function security_net_peersid_cmp(). The function |
4477 | * returns zero if the value in @sid is valid (although it may be SECSID_NULL) |
4478 | * or -EACCES if @sid is invalid due to inconsistencies with the different |
4479 | * peer labels. |
4480 | * |
4481 | */ |
4482 | static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid) |
4483 | { |
4484 | int err; |
4485 | u32 xfrm_sid; |
4486 | u32 nlbl_sid; |
4487 | u32 nlbl_type; |
4488 | |
4489 | err = selinux_xfrm_skb_sid(skb, &xfrm_sid); |
4490 | if (unlikely(err)) |
4491 | return -EACCES; |
4492 | err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid); |
4493 | if (unlikely(err)) |
4494 | return -EACCES; |
4495 | |
4496 | err = security_net_peersid_resolve(nlbl_sid, |
4497 | nlbl_type, xfrm_sid, sid); |
4498 | if (unlikely(err)) { |
4499 | pr_warn( |
4500 | "SELinux: failure in selinux_skb_peerlbl_sid()," |
4501 | " unable to determine packet's peer label\n" ); |
4502 | return -EACCES; |
4503 | } |
4504 | |
4505 | return 0; |
4506 | } |
4507 | |
4508 | /** |
4509 | * selinux_conn_sid - Determine the child socket label for a connection |
4510 | * @sk_sid: the parent socket's SID |
4511 | * @skb_sid: the packet's SID |
4512 | * @conn_sid: the resulting connection SID |
4513 | * |
4514 | * If @skb_sid is valid then the user:role:type information from @sk_sid is |
4515 | * combined with the MLS information from @skb_sid in order to create |
4516 | * @conn_sid. If @skb_sid is not valid then @conn_sid is simply a copy |
4517 | * of @sk_sid. Returns zero on success, negative values on failure. |
4518 | * |
4519 | */ |
4520 | static int selinux_conn_sid(u32 sk_sid, u32 skb_sid, u32 *conn_sid) |
4521 | { |
4522 | int err = 0; |
4523 | |
4524 | if (skb_sid != SECSID_NULL) |
4525 | err = security_sid_mls_copy(sk_sid, skb_sid, |
4526 | conn_sid); |
4527 | else |
4528 | *conn_sid = sk_sid; |
4529 | |
4530 | return err; |
4531 | } |
4532 | |
4533 | /* socket security operations */ |
4534 | |
4535 | static int socket_sockcreate_sid(const struct task_security_struct *tsec, |
4536 | u16 secclass, u32 *socksid) |
4537 | { |
4538 | if (tsec->sockcreate_sid > SECSID_NULL) { |
4539 | *socksid = tsec->sockcreate_sid; |
4540 | return 0; |
4541 | } |
4542 | |
4543 | return security_transition_sid(tsec->sid, tsec->sid, |
4544 | secclass, NULL, socksid); |
4545 | } |
4546 | |
4547 | static int sock_has_perm(struct sock *sk, u32 perms) |
4548 | { |
4549 | struct sk_security_struct *sksec = sk->sk_security; |
4550 | struct common_audit_data ad; |
4551 | struct lsm_network_audit net; |
4552 | |
4553 | if (sksec->sid == SECINITSID_KERNEL) |
4554 | return 0; |
4555 | |
4556 | ad_net_init_from_sk(ad: &ad, net: &net, sk); |
4557 | |
4558 | return avc_has_perm(current_sid(), sksec->sid, sksec->sclass, perms, |
4559 | &ad); |
4560 | } |
4561 | |
4562 | static int selinux_socket_create(int family, int type, |
4563 | int protocol, int kern) |
4564 | { |
4565 | const struct task_security_struct *tsec = selinux_cred(current_cred()); |
4566 | u32 newsid; |
4567 | u16 secclass; |
4568 | int rc; |
4569 | |
4570 | if (kern) |
4571 | return 0; |
4572 | |
4573 | secclass = socket_type_to_security_class(family, type, protocol); |
4574 | rc = socket_sockcreate_sid(tsec, secclass, socksid: &newsid); |
4575 | if (rc) |
4576 | return rc; |
4577 | |
4578 | return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL); |
4579 | } |
4580 | |
4581 | static int selinux_socket_post_create(struct socket *sock, int family, |
4582 | int type, int protocol, int kern) |
4583 | { |
4584 | const struct task_security_struct *tsec = selinux_cred(current_cred()); |
4585 | struct inode_security_struct *isec = inode_security_novalidate(inode: SOCK_INODE(socket: sock)); |
4586 | struct sk_security_struct *sksec; |
4587 | u16 sclass = socket_type_to_security_class(family, type, protocol); |
4588 | u32 sid = SECINITSID_KERNEL; |
4589 | int err = 0; |
4590 | |
4591 | if (!kern) { |
4592 | err = socket_sockcreate_sid(tsec, secclass: sclass, socksid: &sid); |
4593 | if (err) |
4594 | return err; |
4595 | } |
4596 | |
4597 | isec->sclass = sclass; |
4598 | isec->sid = sid; |
4599 | isec->initialized = LABEL_INITIALIZED; |
4600 | |
4601 | if (sock->sk) { |
4602 | sksec = sock->sk->sk_security; |
4603 | sksec->sclass = sclass; |
4604 | sksec->sid = sid; |
4605 | /* Allows detection of the first association on this socket */ |
4606 | if (sksec->sclass == SECCLASS_SCTP_SOCKET) |
4607 | sksec->sctp_assoc_state = SCTP_ASSOC_UNSET; |
4608 | |
4609 | err = selinux_netlbl_socket_post_create(sock->sk, family); |
4610 | } |
4611 | |
4612 | return err; |
4613 | } |
4614 | |
4615 | static int selinux_socket_socketpair(struct socket *socka, |
4616 | struct socket *sockb) |
4617 | { |
4618 | struct sk_security_struct *sksec_a = socka->sk->sk_security; |
4619 | struct sk_security_struct *sksec_b = sockb->sk->sk_security; |
4620 | |
4621 | sksec_a->peer_sid = sksec_b->sid; |
4622 | sksec_b->peer_sid = sksec_a->sid; |
4623 | |
4624 | return 0; |
4625 | } |
4626 | |
4627 | /* Range of port numbers used to automatically bind. |
4628 | Need to determine whether we should perform a name_bind |
4629 | permission check between the socket and the port number. */ |
4630 | |
4631 | static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen) |
4632 | { |
4633 | struct sock *sk = sock->sk; |
4634 | struct sk_security_struct *sksec = sk->sk_security; |
4635 | u16 family; |
4636 | int err; |
4637 | |
4638 | err = sock_has_perm(sk, SOCKET__BIND); |
4639 | if (err) |
4640 | goto out; |
4641 | |
4642 | /* If PF_INET or PF_INET6, check name_bind permission for the port. */ |
4643 | family = sk->sk_family; |
4644 | if (family == PF_INET || family == PF_INET6) { |
4645 | char *addrp; |
4646 | struct common_audit_data ad; |
4647 | struct lsm_network_audit net = {0,}; |
4648 | struct sockaddr_in *addr4 = NULL; |
4649 | struct sockaddr_in6 *addr6 = NULL; |
4650 | u16 family_sa; |
4651 | unsigned short snum; |
4652 | u32 sid, node_perm; |
4653 | |
4654 | /* |
4655 | * sctp_bindx(3) calls via selinux_sctp_bind_connect() |
4656 | * that validates multiple binding addresses. Because of this |
4657 | * need to check address->sa_family as it is possible to have |
4658 | * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET. |
4659 | */ |
4660 | if (addrlen < offsetofend(struct sockaddr, sa_family)) |
4661 | return -EINVAL; |
4662 | family_sa = address->sa_family; |
4663 | switch (family_sa) { |
4664 | case AF_UNSPEC: |
4665 | case AF_INET: |
4666 | if (addrlen < sizeof(struct sockaddr_in)) |
4667 | return -EINVAL; |
4668 | addr4 = (struct sockaddr_in *)address; |
4669 | if (family_sa == AF_UNSPEC) { |
4670 | /* see __inet_bind(), we only want to allow |
4671 | * AF_UNSPEC if the address is INADDR_ANY |
4672 | */ |
4673 | if (addr4->sin_addr.s_addr != htonl(INADDR_ANY)) |
4674 | goto err_af; |
4675 | family_sa = AF_INET; |
4676 | } |
4677 | snum = ntohs(addr4->sin_port); |
4678 | addrp = (char *)&addr4->sin_addr.s_addr; |
4679 | break; |
4680 | case AF_INET6: |
4681 | if (addrlen < SIN6_LEN_RFC2133) |
4682 | return -EINVAL; |
4683 | addr6 = (struct sockaddr_in6 *)address; |
4684 | snum = ntohs(addr6->sin6_port); |
4685 | addrp = (char *)&addr6->sin6_addr.s6_addr; |
4686 | break; |
4687 | default: |
4688 | goto err_af; |
4689 | } |
4690 | |
4691 | ad.type = LSM_AUDIT_DATA_NET; |
4692 | ad.u.net = &net; |
4693 | ad.u.net->sport = htons(snum); |
4694 | ad.u.net->family = family_sa; |
4695 | |
4696 | if (snum) { |
4697 | int low, high; |
4698 | |
4699 | inet_get_local_port_range(net: sock_net(sk), low: &low, high: &high); |
4700 | |
4701 | if (inet_port_requires_bind_service(net: sock_net(sk), port: snum) || |
4702 | snum < low || snum > high) { |
4703 | err = sel_netport_sid(sk->sk_protocol, |
4704 | snum, &sid); |
4705 | if (err) |
4706 | goto out; |
4707 | err = avc_has_perm(sksec->sid, sid, |
4708 | sksec->sclass, |
4709 | SOCKET__NAME_BIND, &ad); |
4710 | if (err) |
4711 | goto out; |
4712 | } |
4713 | } |
4714 | |
4715 | switch (sksec->sclass) { |
4716 | case SECCLASS_TCP_SOCKET: |
4717 | node_perm = TCP_SOCKET__NODE_BIND; |
4718 | break; |
4719 | |
4720 | case SECCLASS_UDP_SOCKET: |
4721 | node_perm = UDP_SOCKET__NODE_BIND; |
4722 | break; |
4723 | |
4724 | case SECCLASS_DCCP_SOCKET: |
4725 | node_perm = DCCP_SOCKET__NODE_BIND; |
4726 | break; |
4727 | |
4728 | case SECCLASS_SCTP_SOCKET: |
4729 | node_perm = SCTP_SOCKET__NODE_BIND; |
4730 | break; |
4731 | |
4732 | default: |
4733 | node_perm = RAWIP_SOCKET__NODE_BIND; |
4734 | break; |
4735 | } |
4736 | |
4737 | err = sel_netnode_sid(addrp, family_sa, &sid); |
4738 | if (err) |
4739 | goto out; |
4740 | |
4741 | if (family_sa == AF_INET) |
4742 | ad.u.net->v4info.saddr = addr4->sin_addr.s_addr; |
4743 | else |
4744 | ad.u.net->v6info.saddr = addr6->sin6_addr; |
4745 | |
4746 | err = avc_has_perm(sksec->sid, sid, |
4747 | sksec->sclass, node_perm, &ad); |
4748 | if (err) |
4749 | goto out; |
4750 | } |
4751 | out: |
4752 | return err; |
4753 | err_af: |
4754 | /* Note that SCTP services expect -EINVAL, others -EAFNOSUPPORT. */ |
4755 | if (sksec->sclass == SECCLASS_SCTP_SOCKET) |
4756 | return -EINVAL; |
4757 | return -EAFNOSUPPORT; |
4758 | } |
4759 | |
4760 | /* This supports connect(2) and SCTP connect services such as sctp_connectx(3) |
4761 | * and sctp_sendmsg(3) as described in Documentation/security/SCTP.rst |
4762 | */ |
4763 | static int selinux_socket_connect_helper(struct socket *sock, |
4764 | struct sockaddr *address, int addrlen) |
4765 | { |
4766 | struct sock *sk = sock->sk; |
4767 | struct sk_security_struct *sksec = sk->sk_security; |
4768 | int err; |
4769 | |
4770 | err = sock_has_perm(sk, SOCKET__CONNECT); |
4771 | if (err) |
4772 | return err; |
4773 | if (addrlen < offsetofend(struct sockaddr, sa_family)) |
4774 | return -EINVAL; |
4775 | |
4776 | /* connect(AF_UNSPEC) has special handling, as it is a documented |
4777 | * way to disconnect the socket |
4778 | */ |
4779 | if (address->sa_family == AF_UNSPEC) |
4780 | return 0; |
4781 | |
4782 | /* |
4783 | * If a TCP, DCCP or SCTP socket, check name_connect permission |
4784 | * for the port. |
4785 | */ |
4786 | if (sksec->sclass == SECCLASS_TCP_SOCKET || |
4787 | sksec->sclass == SECCLASS_DCCP_SOCKET || |
4788 | sksec->sclass == SECCLASS_SCTP_SOCKET) { |
4789 | struct common_audit_data ad; |
4790 | struct lsm_network_audit net = {0,}; |
4791 | struct sockaddr_in *addr4 = NULL; |
4792 | struct sockaddr_in6 *addr6 = NULL; |
4793 | unsigned short snum; |
4794 | u32 sid, perm; |
4795 | |
4796 | /* sctp_connectx(3) calls via selinux_sctp_bind_connect() |
4797 | * that validates multiple connect addresses. Because of this |
4798 | * need to check address->sa_family as it is possible to have |
4799 | * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET. |
4800 | */ |
4801 | switch (address->sa_family) { |
4802 | case AF_INET: |
4803 | addr4 = (struct sockaddr_in *)address; |
4804 | if (addrlen < sizeof(struct sockaddr_in)) |
4805 | return -EINVAL; |
4806 | snum = ntohs(addr4->sin_port); |
4807 | break; |
4808 | case AF_INET6: |
4809 | addr6 = (struct sockaddr_in6 *)address; |
4810 | if (addrlen < SIN6_LEN_RFC2133) |
4811 | return -EINVAL; |
4812 | snum = ntohs(addr6->sin6_port); |
4813 | break; |
4814 | default: |
4815 | /* Note that SCTP services expect -EINVAL, whereas |
4816 | * others expect -EAFNOSUPPORT. |
4817 | */ |
4818 | if (sksec->sclass == SECCLASS_SCTP_SOCKET) |
4819 | return -EINVAL; |
4820 | else |
4821 | return -EAFNOSUPPORT; |
4822 | } |
4823 | |
4824 | err = sel_netport_sid(sk->sk_protocol, snum, &sid); |
4825 | if (err) |
4826 | return err; |
4827 | |
4828 | switch (sksec->sclass) { |
4829 | case SECCLASS_TCP_SOCKET: |
4830 | perm = TCP_SOCKET__NAME_CONNECT; |
4831 | break; |
4832 | case SECCLASS_DCCP_SOCKET: |
4833 | perm = DCCP_SOCKET__NAME_CONNECT; |
4834 | break; |
4835 | case SECCLASS_SCTP_SOCKET: |
4836 | perm = SCTP_SOCKET__NAME_CONNECT; |
4837 | break; |
4838 | } |
4839 | |
4840 | ad.type = LSM_AUDIT_DATA_NET; |
4841 | ad.u.net = &net; |
4842 | ad.u.net->dport = htons(snum); |
4843 | ad.u.net->family = address->sa_family; |
4844 | err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad); |
4845 | if (err) |
4846 | return err; |
4847 | } |
4848 | |
4849 | return 0; |
4850 | } |
4851 | |
4852 | /* Supports connect(2), see comments in selinux_socket_connect_helper() */ |
4853 | static int selinux_socket_connect(struct socket *sock, |
4854 | struct sockaddr *address, int addrlen) |
4855 | { |
4856 | int err; |
4857 | struct sock *sk = sock->sk; |
4858 | |
4859 | err = selinux_socket_connect_helper(sock, address, addrlen); |
4860 | if (err) |
4861 | return err; |
4862 | |
4863 | return selinux_netlbl_socket_connect(sk, address); |
4864 | } |
4865 | |
4866 | static int selinux_socket_listen(struct socket *sock, int backlog) |
4867 | { |
4868 | return sock_has_perm(sock->sk, SOCKET__LISTEN); |
4869 | } |
4870 | |
4871 | static int selinux_socket_accept(struct socket *sock, struct socket *newsock) |
4872 | { |
4873 | int err; |
4874 | struct inode_security_struct *isec; |
4875 | struct inode_security_struct *newisec; |
4876 | u16 sclass; |
4877 | u32 sid; |
4878 | |
4879 | err = sock_has_perm(sock->sk, SOCKET__ACCEPT); |
4880 | if (err) |
4881 | return err; |
4882 | |
4883 | isec = inode_security_novalidate(inode: SOCK_INODE(socket: sock)); |
4884 | spin_lock(lock: &isec->lock); |
4885 | sclass = isec->sclass; |
4886 | sid = isec->sid; |
4887 | spin_unlock(lock: &isec->lock); |
4888 | |
4889 | newisec = inode_security_novalidate(inode: SOCK_INODE(socket: newsock)); |
4890 | newisec->sclass = sclass; |
4891 | newisec->sid = sid; |
4892 | newisec->initialized = LABEL_INITIALIZED; |
4893 | |
4894 | return 0; |
4895 | } |
4896 | |
4897 | static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg, |
4898 | int size) |
4899 | { |
4900 | return sock_has_perm(sock->sk, SOCKET__WRITE); |
4901 | } |
4902 | |
4903 | static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg, |
4904 | int size, int flags) |
4905 | { |
4906 | return sock_has_perm(sock->sk, SOCKET__READ); |
4907 | } |
4908 | |
4909 | static int selinux_socket_getsockname(struct socket *sock) |
4910 | { |
4911 | return sock_has_perm(sock->sk, SOCKET__GETATTR); |
4912 | } |
4913 | |
4914 | static int selinux_socket_getpeername(struct socket *sock) |
4915 | { |
4916 | return sock_has_perm(sock->sk, SOCKET__GETATTR); |
4917 | } |
4918 | |
4919 | static int selinux_socket_setsockopt(struct socket *sock, int level, int optname) |
4920 | { |
4921 | int err; |
4922 | |
4923 | err = sock_has_perm(sock->sk, SOCKET__SETOPT); |
4924 | if (err) |
4925 | return err; |
4926 | |
4927 | return selinux_netlbl_socket_setsockopt(sock, level, optname); |
4928 | } |
4929 | |
4930 | static int selinux_socket_getsockopt(struct socket *sock, int level, |
4931 | int optname) |
4932 | { |
4933 | return sock_has_perm(sock->sk, SOCKET__GETOPT); |
4934 | } |
4935 | |
4936 | static int selinux_socket_shutdown(struct socket *sock, int how) |
4937 | { |
4938 | return sock_has_perm(sock->sk, SOCKET__SHUTDOWN); |
4939 | } |
4940 | |
4941 | static int selinux_socket_unix_stream_connect(struct sock *sock, |
4942 | struct sock *other, |
4943 | struct sock *newsk) |
4944 | { |
4945 | struct sk_security_struct *sksec_sock = sock->sk_security; |
4946 | struct sk_security_struct *sksec_other = other->sk_security; |
4947 | struct sk_security_struct *sksec_new = newsk->sk_security; |
4948 | struct common_audit_data ad; |
4949 | struct lsm_network_audit net; |
4950 | int err; |
4951 | |
4952 | ad_net_init_from_sk(ad: &ad, net: &net, sk: other); |
4953 | |
4954 | err = avc_has_perm(sksec_sock->sid, sksec_other->sid, |
4955 | sksec_other->sclass, |
4956 | UNIX_STREAM_SOCKET__CONNECTTO, &ad); |
4957 | if (err) |
4958 | return err; |
4959 | |
4960 | /* server child socket */ |
4961 | sksec_new->peer_sid = sksec_sock->sid; |
4962 | err = security_sid_mls_copy(sksec_other->sid, |
4963 | sksec_sock->sid, &sksec_new->sid); |
4964 | if (err) |
4965 | return err; |
4966 | |
4967 | /* connecting socket */ |
4968 | sksec_sock->peer_sid = sksec_new->sid; |
4969 | |
4970 | return 0; |
4971 | } |
4972 | |
4973 | static int selinux_socket_unix_may_send(struct socket *sock, |
4974 | struct socket *other) |
4975 | { |
4976 | struct sk_security_struct *ssec = sock->sk->sk_security; |
4977 | struct sk_security_struct *osec = other->sk->sk_security; |
4978 | struct common_audit_data ad; |
4979 | struct lsm_network_audit net; |
4980 | |
4981 | ad_net_init_from_sk(ad: &ad, net: &net, sk: other->sk); |
4982 | |
4983 | return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO, |
4984 | &ad); |
4985 | } |
4986 | |
4987 | static int selinux_inet_sys_rcv_skb(struct net *ns, int ifindex, |
4988 | char *addrp, u16 family, u32 peer_sid, |
4989 | struct common_audit_data *ad) |
4990 | { |
4991 | int err; |
4992 | u32 if_sid; |
4993 | u32 node_sid; |
4994 | |
4995 | err = sel_netif_sid(ns, ifindex, &if_sid); |
4996 | if (err) |
4997 | return err; |
4998 | err = avc_has_perm(peer_sid, if_sid, |
4999 | SECCLASS_NETIF, NETIF__INGRESS, ad); |
5000 | if (err) |
5001 | return err; |
5002 | |
5003 | err = sel_netnode_sid(addrp, family, &node_sid); |
5004 | if (err) |
5005 | return err; |
5006 | return avc_has_perm(peer_sid, node_sid, |
5007 | SECCLASS_NODE, NODE__RECVFROM, ad); |
5008 | } |
5009 | |
5010 | static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb, |
5011 | u16 family) |
5012 | { |
5013 | int err = 0; |
5014 | struct sk_security_struct *sksec = sk->sk_security; |
5015 | u32 sk_sid = sksec->sid; |
5016 | struct common_audit_data ad; |
5017 | struct lsm_network_audit net; |
5018 | char *addrp; |
5019 | |
5020 | ad_net_init_from_iif(ad: &ad, net: &net, ifindex: skb->skb_iif, family); |
5021 | err = selinux_parse_skb(skb, ad: &ad, addrp: &addrp, src: 1, NULL); |
5022 | if (err) |
5023 | return err; |
5024 | |
5025 | if (selinux_secmark_enabled()) { |
5026 | err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET, |
5027 | PACKET__RECV, &ad); |
5028 | if (err) |
5029 | return err; |
5030 | } |
5031 | |
5032 | err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad); |
5033 | if (err) |
5034 | return err; |
5035 | err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad); |
5036 | |
5037 | return err; |
5038 | } |
5039 | |
5040 | static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb) |
5041 | { |
5042 | int err, peerlbl_active, secmark_active; |
5043 | struct sk_security_struct *sksec = sk->sk_security; |
5044 | u16 family = sk->sk_family; |
5045 | u32 sk_sid = sksec->sid; |
5046 | struct common_audit_data ad; |
5047 | struct lsm_network_audit net; |
5048 | char *addrp; |
5049 | |
5050 | if (family != PF_INET && family != PF_INET6) |
5051 | return 0; |
5052 | |
5053 | /* Handle mapped IPv4 packets arriving via IPv6 sockets */ |
5054 | if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) |
5055 | family = PF_INET; |
5056 | |
5057 | /* If any sort of compatibility mode is enabled then handoff processing |
5058 | * to the selinux_sock_rcv_skb_compat() function to deal with the |
5059 | * special handling. We do this in an attempt to keep this function |
5060 | * as fast and as clean as possible. */ |
5061 | if (!selinux_policycap_netpeer()) |
5062 | return selinux_sock_rcv_skb_compat(sk, skb, family); |
5063 | |
5064 | secmark_active = selinux_secmark_enabled(); |
5065 | peerlbl_active = selinux_peerlbl_enabled(); |
5066 | if (!secmark_active && !peerlbl_active) |
5067 | return 0; |
5068 | |
5069 | ad_net_init_from_iif(ad: &ad, net: &net, ifindex: skb->skb_iif, family); |
5070 | err = selinux_parse_skb(skb, ad: &ad, addrp: &addrp, src: 1, NULL); |
5071 | if (err) |
5072 | return err; |
5073 | |
5074 | if (peerlbl_active) { |
5075 | u32 peer_sid; |
5076 | |
5077 | err = selinux_skb_peerlbl_sid(skb, family, sid: &peer_sid); |
5078 | if (err) |
5079 | return err; |
5080 | err = selinux_inet_sys_rcv_skb(ns: sock_net(sk), ifindex: skb->skb_iif, |
5081 | addrp, family, peer_sid, ad: &ad); |
5082 | if (err) { |
5083 | selinux_netlbl_err(skb, family, err, 0); |
5084 | return err; |
5085 | } |
5086 | err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER, |
5087 | PEER__RECV, &ad); |
5088 | if (err) { |
5089 | selinux_netlbl_err(skb, family, err, 0); |
5090 | return err; |
5091 | } |
5092 | } |
5093 | |
5094 | if (secmark_active) { |
5095 | err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET, |
5096 | PACKET__RECV, &ad); |
5097 | if (err) |
5098 | return err; |
5099 | } |
5100 | |
5101 | return err; |
5102 | } |
5103 | |
5104 | static int selinux_socket_getpeersec_stream(struct socket *sock, |
5105 | sockptr_t optval, sockptr_t optlen, |
5106 | unsigned int len) |
5107 | { |
5108 | int err = 0; |
5109 | char *scontext = NULL; |
5110 | u32 scontext_len; |
5111 | struct sk_security_struct *sksec = sock->sk->sk_security; |
5112 | u32 peer_sid = SECSID_NULL; |
5113 | |
5114 | if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET || |
5115 | sksec->sclass == SECCLASS_TCP_SOCKET || |
5116 | sksec->sclass == SECCLASS_SCTP_SOCKET) |
5117 | peer_sid = sksec->peer_sid; |
5118 | if (peer_sid == SECSID_NULL) |
5119 | return -ENOPROTOOPT; |
5120 | |
5121 | err = security_sid_to_context(peer_sid, &scontext, |
5122 | &scontext_len); |
5123 | if (err) |
5124 | return err; |
5125 | if (scontext_len > len) { |
5126 | err = -ERANGE; |
5127 | goto out_len; |
5128 | } |
5129 | |
5130 | if (copy_to_sockptr(dst: optval, src: scontext, size: scontext_len)) |
5131 | err = -EFAULT; |
5132 | out_len: |
5133 | if (copy_to_sockptr(dst: optlen, src: &scontext_len, size: sizeof(scontext_len))) |
5134 | err = -EFAULT; |
5135 | kfree(objp: scontext); |
5136 | return err; |
5137 | } |
5138 | |
5139 | static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid) |
5140 | { |
5141 | u32 peer_secid = SECSID_NULL; |
5142 | u16 family; |
5143 | struct inode_security_struct *isec; |
5144 | |
5145 | if (skb && skb->protocol == htons(ETH_P_IP)) |
5146 | family = PF_INET; |
5147 | else if (skb && skb->protocol == htons(ETH_P_IPV6)) |
5148 | family = PF_INET6; |
5149 | else if (sock) |
5150 | family = sock->sk->sk_family; |
5151 | else |
5152 | goto out; |
5153 | |
5154 | if (sock && family == PF_UNIX) { |
5155 | isec = inode_security_novalidate(inode: SOCK_INODE(socket: sock)); |
5156 | peer_secid = isec->sid; |
5157 | } else if (skb) |
5158 | selinux_skb_peerlbl_sid(skb, family, sid: &peer_secid); |
5159 | |
5160 | out: |
5161 | *secid = peer_secid; |
5162 | if (peer_secid == SECSID_NULL) |
5163 | return -EINVAL; |
5164 | return 0; |
5165 | } |
5166 | |
5167 | static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority) |
5168 | { |
5169 | struct sk_security_struct *sksec; |
5170 | |
5171 | sksec = kzalloc(sizeof(*sksec), priority); |
5172 | if (!sksec) |
5173 | return -ENOMEM; |
5174 | |
5175 | sksec->peer_sid = SECINITSID_UNLABELED; |
5176 | sksec->sid = SECINITSID_UNLABELED; |
5177 | sksec->sclass = SECCLASS_SOCKET; |
5178 | selinux_netlbl_sk_security_reset(sksec); |
5179 | sk->sk_security = sksec; |
5180 | |
5181 | return 0; |
5182 | } |
5183 | |
5184 | static void selinux_sk_free_security(struct sock *sk) |
5185 | { |
5186 | struct sk_security_struct *sksec = sk->sk_security; |
5187 | |
5188 | sk->sk_security = NULL; |
5189 | selinux_netlbl_sk_security_free(sksec); |
5190 | kfree(objp: sksec); |
5191 | } |
5192 | |
5193 | static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk) |
5194 | { |
5195 | struct sk_security_struct *sksec = sk->sk_security; |
5196 | struct sk_security_struct *newsksec = newsk->sk_security; |
5197 | |
5198 | newsksec->sid = sksec->sid; |
5199 | newsksec->peer_sid = sksec->peer_sid; |
5200 | newsksec->sclass = sksec->sclass; |
5201 | |
5202 | selinux_netlbl_sk_security_reset(newsksec); |
5203 | } |
5204 | |
5205 | static void selinux_sk_getsecid(const struct sock *sk, u32 *secid) |
5206 | { |
5207 | if (!sk) |
5208 | *secid = SECINITSID_ANY_SOCKET; |
5209 | else { |
5210 | const struct sk_security_struct *sksec = sk->sk_security; |
5211 | |
5212 | *secid = sksec->sid; |
5213 | } |
5214 | } |
5215 | |
5216 | static void selinux_sock_graft(struct sock *sk, struct socket *parent) |
5217 | { |
5218 | struct inode_security_struct *isec = |
5219 | inode_security_novalidate(inode: SOCK_INODE(socket: parent)); |
5220 | struct sk_security_struct *sksec = sk->sk_security; |
5221 | |
5222 | if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 || |
5223 | sk->sk_family == PF_UNIX) |
5224 | isec->sid = sksec->sid; |
5225 | sksec->sclass = isec->sclass; |
5226 | } |
5227 | |
5228 | /* |
5229 | * Determines peer_secid for the asoc and updates socket's peer label |
5230 | * if it's the first association on the socket. |
5231 | */ |
5232 | static int selinux_sctp_process_new_assoc(struct sctp_association *asoc, |
5233 | struct sk_buff *skb) |
5234 | { |
5235 | struct sock *sk = asoc->base.sk; |
5236 | u16 family = sk->sk_family; |
5237 | struct sk_security_struct *sksec = sk->sk_security; |
5238 | struct common_audit_data ad; |
5239 | struct lsm_network_audit net; |
5240 | int err; |
5241 | |
5242 | /* handle mapped IPv4 packets arriving via IPv6 sockets */ |
5243 | if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) |
5244 | family = PF_INET; |
5245 | |
5246 | if (selinux_peerlbl_enabled()) { |
5247 | asoc->peer_secid = SECSID_NULL; |
5248 | |
5249 | /* This will return peer_sid = SECSID_NULL if there are |
5250 | * no peer labels, see security_net_peersid_resolve(). |
5251 | */ |
5252 | err = selinux_skb_peerlbl_sid(skb, family, sid: &asoc->peer_secid); |
5253 | if (err) |
5254 | return err; |
5255 | |
5256 | if (asoc->peer_secid == SECSID_NULL) |
5257 | asoc->peer_secid = SECINITSID_UNLABELED; |
5258 | } else { |
5259 | asoc->peer_secid = SECINITSID_UNLABELED; |
5260 | } |
5261 | |
5262 | if (sksec->sctp_assoc_state == SCTP_ASSOC_UNSET) { |
5263 | sksec->sctp_assoc_state = SCTP_ASSOC_SET; |
5264 | |
5265 | /* Here as first association on socket. As the peer SID |
5266 | * was allowed by peer recv (and the netif/node checks), |
5267 | * then it is approved by policy and used as the primary |
5268 | * peer SID for getpeercon(3). |
5269 | */ |
5270 | sksec->peer_sid = asoc->peer_secid; |
5271 | } else if (sksec->peer_sid != asoc->peer_secid) { |
5272 | /* Other association peer SIDs are checked to enforce |
5273 | * consistency among the peer SIDs. |
5274 | */ |
5275 | ad_net_init_from_sk(ad: &ad, net: &net, sk: asoc->base.sk); |
5276 | err = avc_has_perm(sksec->peer_sid, asoc->peer_secid, |
5277 | sksec->sclass, SCTP_SOCKET__ASSOCIATION, |
5278 | &ad); |
5279 | if (err) |
5280 | return err; |
5281 | } |
5282 | return 0; |
5283 | } |
5284 | |
5285 | /* Called whenever SCTP receives an INIT or COOKIE ECHO chunk. This |
5286 | * happens on an incoming connect(2), sctp_connectx(3) or |
5287 | * sctp_sendmsg(3) (with no association already present). |
5288 | */ |
5289 | static int selinux_sctp_assoc_request(struct sctp_association *asoc, |
5290 | struct sk_buff *skb) |
5291 | { |
5292 | struct sk_security_struct *sksec = asoc->base.sk->sk_security; |
5293 | u32 conn_sid; |
5294 | int err; |
5295 | |
5296 | if (!selinux_policycap_extsockclass()) |
5297 | return 0; |
5298 | |
5299 | err = selinux_sctp_process_new_assoc(asoc, skb); |
5300 | if (err) |
5301 | return err; |
5302 | |
5303 | /* Compute the MLS component for the connection and store |
5304 | * the information in asoc. This will be used by SCTP TCP type |
5305 | * sockets and peeled off connections as they cause a new |
5306 | * socket to be generated. selinux_sctp_sk_clone() will then |
5307 | * plug this into the new socket. |
5308 | */ |
5309 | err = selinux_conn_sid(sk_sid: sksec->sid, skb_sid: asoc->peer_secid, conn_sid: &conn_sid); |
5310 | if (err) |
5311 | return err; |
5312 | |
5313 | asoc->secid = conn_sid; |
5314 | |
5315 | /* Set any NetLabel labels including CIPSO/CALIPSO options. */ |
5316 | return selinux_netlbl_sctp_assoc_request(asoc, skb); |
5317 | } |
5318 | |
5319 | /* Called when SCTP receives a COOKIE ACK chunk as the final |
5320 | * response to an association request (initited by us). |
5321 | */ |
5322 | static int selinux_sctp_assoc_established(struct sctp_association *asoc, |
5323 | struct sk_buff *skb) |
5324 | { |
5325 | struct sk_security_struct *sksec = asoc->base.sk->sk_security; |
5326 | |
5327 | if (!selinux_policycap_extsockclass()) |
5328 | return 0; |
5329 | |
5330 | /* Inherit secid from the parent socket - this will be picked up |
5331 | * by selinux_sctp_sk_clone() if the association gets peeled off |
5332 | * into a new socket. |
5333 | */ |
5334 | asoc->secid = sksec->sid; |
5335 | |
5336 | return selinux_sctp_process_new_assoc(asoc, skb); |
5337 | } |
5338 | |
5339 | /* Check if sctp IPv4/IPv6 addresses are valid for binding or connecting |
5340 | * based on their @optname. |
5341 | */ |
5342 | static int selinux_sctp_bind_connect(struct sock *sk, int optname, |
5343 | struct sockaddr *address, |
5344 | int addrlen) |
5345 | { |
5346 | int len, err = 0, walk_size = 0; |
5347 | void *addr_buf; |
5348 | struct sockaddr *addr; |
5349 | struct socket *sock; |
5350 | |
5351 | if (!selinux_policycap_extsockclass()) |
5352 | return 0; |
5353 | |
5354 | /* Process one or more addresses that may be IPv4 or IPv6 */ |
5355 | sock = sk->sk_socket; |
5356 | addr_buf = address; |
5357 | |
5358 | while (walk_size < addrlen) { |
5359 | if (walk_size + sizeof(sa_family_t) > addrlen) |
5360 | return -EINVAL; |
5361 | |
5362 | addr = addr_buf; |
5363 | switch (addr->sa_family) { |
5364 | case AF_UNSPEC: |
5365 | case AF_INET: |
5366 | len = sizeof(struct sockaddr_in); |
5367 | break; |
5368 | case AF_INET6: |
5369 | len = sizeof(struct sockaddr_in6); |
5370 | break; |
5371 | default: |
5372 | return -EINVAL; |
5373 | } |
5374 | |
5375 | if (walk_size + len > addrlen) |
5376 | return -EINVAL; |
5377 | |
5378 | err = -EINVAL; |
5379 | switch (optname) { |
5380 | /* Bind checks */ |
5381 | case SCTP_PRIMARY_ADDR: |
5382 | case SCTP_SET_PEER_PRIMARY_ADDR: |
5383 | case SCTP_SOCKOPT_BINDX_ADD: |
5384 | err = selinux_socket_bind(sock, address: addr, addrlen: len); |
5385 | break; |
5386 | /* Connect checks */ |
5387 | case SCTP_SOCKOPT_CONNECTX: |
5388 | case SCTP_PARAM_SET_PRIMARY: |
5389 | case SCTP_PARAM_ADD_IP: |
5390 | case SCTP_SENDMSG_CONNECT: |
5391 | err = selinux_socket_connect_helper(sock, address: addr, addrlen: len); |
5392 | if (err) |
5393 | return err; |
5394 | |
5395 | /* As selinux_sctp_bind_connect() is called by the |
5396 | * SCTP protocol layer, the socket is already locked, |
5397 | * therefore selinux_netlbl_socket_connect_locked() |
5398 | * is called here. The situations handled are: |
5399 | * sctp_connectx(3), sctp_sendmsg(3), sendmsg(2), |
5400 | * whenever a new IP address is added or when a new |
5401 | * primary address is selected. |
5402 | * Note that an SCTP connect(2) call happens before |
5403 | * the SCTP protocol layer and is handled via |
5404 | * selinux_socket_connect(). |
5405 | */ |
5406 | err = selinux_netlbl_socket_connect_locked(sk, addr); |
5407 | break; |
5408 | } |
5409 | |
5410 | if (err) |
5411 | return err; |
5412 | |
5413 | addr_buf += len; |
5414 | walk_size += len; |
5415 | } |
5416 | |
5417 | return 0; |
5418 | } |
5419 | |
5420 | /* Called whenever a new socket is created by accept(2) or sctp_peeloff(3). */ |
5421 | static void selinux_sctp_sk_clone(struct sctp_association *asoc, struct sock *sk, |
5422 | struct sock *newsk) |
5423 | { |
5424 | struct sk_security_struct *sksec = sk->sk_security; |
5425 | struct sk_security_struct *newsksec = newsk->sk_security; |
5426 | |
5427 | /* If policy does not support SECCLASS_SCTP_SOCKET then call |
5428 | * the non-sctp clone version. |
5429 | */ |
5430 | if (!selinux_policycap_extsockclass()) |
5431 | return selinux_sk_clone_security(sk, newsk); |
5432 | |
5433 | newsksec->sid = asoc->secid; |
5434 | newsksec->peer_sid = asoc->peer_secid; |
5435 | newsksec->sclass = sksec->sclass; |
5436 | selinux_netlbl_sctp_sk_clone(sk, newsk); |
5437 | } |
5438 | |
5439 | static int selinux_mptcp_add_subflow(struct sock *sk, struct sock *ssk) |
5440 | { |
5441 | struct sk_security_struct *ssksec = ssk->sk_security; |
5442 | struct sk_security_struct *sksec = sk->sk_security; |
5443 | |
5444 | ssksec->sclass = sksec->sclass; |
5445 | ssksec->sid = sksec->sid; |
5446 | |
5447 | /* replace the existing subflow label deleting the existing one |
5448 | * and re-recreating a new label using the updated context |
5449 | */ |
5450 | selinux_netlbl_sk_security_free(ssksec); |
5451 | return selinux_netlbl_socket_post_create(ssk, ssk->sk_family); |
5452 | } |
5453 | |
5454 | static int selinux_inet_conn_request(const struct sock *sk, struct sk_buff *skb, |
5455 | struct request_sock *req) |
5456 | { |
5457 | struct sk_security_struct *sksec = sk->sk_security; |
5458 | int err; |
5459 | u16 family = req->rsk_ops->family; |
5460 | u32 connsid; |
5461 | u32 peersid; |
5462 | |
5463 | err = selinux_skb_peerlbl_sid(skb, family, sid: &peersid); |
5464 | if (err) |
5465 | return err; |
5466 | err = selinux_conn_sid(sk_sid: sksec->sid, skb_sid: peersid, conn_sid: &connsid); |
5467 | if (err) |
5468 | return err; |
5469 | req->secid = connsid; |
5470 | req->peer_secid = peersid; |
5471 | |
5472 | return selinux_netlbl_inet_conn_request(req, family); |
5473 | } |
5474 | |
5475 | static void selinux_inet_csk_clone(struct sock *newsk, |
5476 | const struct request_sock *req) |
5477 | { |
5478 | struct sk_security_struct *newsksec = newsk->sk_security; |
5479 | |
5480 | newsksec->sid = req->secid; |
5481 | newsksec->peer_sid = req->peer_secid; |
5482 | /* NOTE: Ideally, we should also get the isec->sid for the |
5483 | new socket in sync, but we don't have the isec available yet. |
5484 | So we will wait until sock_graft to do it, by which |
5485 | time it will have been created and available. */ |
5486 | |
5487 | /* We don't need to take any sort of lock here as we are the only |
5488 | * thread with access to newsksec */ |
5489 | selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family); |
5490 | } |
5491 | |
5492 | static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb) |
5493 | { |
5494 | u16 family = sk->sk_family; |
5495 | struct sk_security_struct *sksec = sk->sk_security; |
5496 | |
5497 | /* handle mapped IPv4 packets arriving via IPv6 sockets */ |
5498 | if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) |
5499 | family = PF_INET; |
5500 | |
5501 | selinux_skb_peerlbl_sid(skb, family, sid: &sksec->peer_sid); |
5502 | } |
5503 | |
5504 | static int selinux_secmark_relabel_packet(u32 sid) |
5505 | { |
5506 | const struct task_security_struct *tsec; |
5507 | u32 tsid; |
5508 | |
5509 | tsec = selinux_cred(current_cred()); |
5510 | tsid = tsec->sid; |
5511 | |
5512 | return avc_has_perm(tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO, |
5513 | NULL); |
5514 | } |
5515 | |
5516 | static void selinux_secmark_refcount_inc(void) |
5517 | { |
5518 | atomic_inc(v: &selinux_secmark_refcount); |
5519 | } |
5520 | |
5521 | static void selinux_secmark_refcount_dec(void) |
5522 | { |
5523 | atomic_dec(v: &selinux_secmark_refcount); |
5524 | } |
5525 | |
5526 | static void selinux_req_classify_flow(const struct request_sock *req, |
5527 | struct flowi_common *flic) |
5528 | { |
5529 | flic->flowic_secid = req->secid; |
5530 | } |
5531 | |
5532 | static int selinux_tun_dev_alloc_security(void **security) |
5533 | { |
5534 | struct tun_security_struct *tunsec; |
5535 | |
5536 | tunsec = kzalloc(sizeof(*tunsec), GFP_KERNEL); |
5537 | if (!tunsec) |
5538 | return -ENOMEM; |
5539 | tunsec->sid = current_sid(); |
5540 | |
5541 | *security = tunsec; |
5542 | return 0; |
5543 | } |
5544 | |
5545 | static void selinux_tun_dev_free_security(void *security) |
5546 | { |
5547 | kfree(objp: security); |
5548 | } |
5549 | |
5550 | static int selinux_tun_dev_create(void) |
5551 | { |
5552 | u32 sid = current_sid(); |
5553 | |
5554 | /* we aren't taking into account the "sockcreate" SID since the socket |
5555 | * that is being created here is not a socket in the traditional sense, |
5556 | * instead it is a private sock, accessible only to the kernel, and |
5557 | * representing a wide range of network traffic spanning multiple |
5558 | * connections unlike traditional sockets - check the TUN driver to |
5559 | * get a better understanding of why this socket is special */ |
5560 | |
5561 | return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE, |
5562 | NULL); |
5563 | } |
5564 | |
5565 | static int selinux_tun_dev_attach_queue(void *security) |
5566 | { |
5567 | struct tun_security_struct *tunsec = security; |
5568 | |
5569 | return avc_has_perm(current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET, |
5570 | TUN_SOCKET__ATTACH_QUEUE, NULL); |
5571 | } |
5572 | |
5573 | static int selinux_tun_dev_attach(struct sock *sk, void *security) |
5574 | { |
5575 | struct tun_security_struct *tunsec = security; |
5576 | struct sk_security_struct *sksec = sk->sk_security; |
5577 | |
5578 | /* we don't currently perform any NetLabel based labeling here and it |
5579 | * isn't clear that we would want to do so anyway; while we could apply |
5580 | * labeling without the support of the TUN user the resulting labeled |
5581 | * traffic from the other end of the connection would almost certainly |
5582 | * cause confusion to the TUN user that had no idea network labeling |
5583 | * protocols were being used */ |
5584 | |
5585 | sksec->sid = tunsec->sid; |
5586 | sksec->sclass = SECCLASS_TUN_SOCKET; |
5587 | |
5588 | return 0; |
5589 | } |
5590 | |
5591 | static int selinux_tun_dev_open(void *security) |
5592 | { |
5593 | struct tun_security_struct *tunsec = security; |
5594 | u32 sid = current_sid(); |
5595 | int err; |
5596 | |
5597 | err = avc_has_perm(sid, tunsec->sid, SECCLASS_TUN_SOCKET, |
5598 | TUN_SOCKET__RELABELFROM, NULL); |
5599 | if (err) |
5600 | return err; |
5601 | err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, |
5602 | TUN_SOCKET__RELABELTO, NULL); |
5603 | if (err) |
5604 | return err; |
5605 | tunsec->sid = sid; |
5606 | |
5607 | return 0; |
5608 | } |
5609 | |
5610 | #ifdef CONFIG_NETFILTER |
5611 | |
5612 | static unsigned int selinux_ip_forward(void *priv, struct sk_buff *skb, |
5613 | const struct nf_hook_state *state) |
5614 | { |
5615 | int ifindex; |
5616 | u16 family; |
5617 | char *addrp; |
5618 | u32 peer_sid; |
5619 | struct common_audit_data ad; |
5620 | struct lsm_network_audit net; |
5621 | int secmark_active, peerlbl_active; |
5622 | |
5623 | if (!selinux_policycap_netpeer()) |
5624 | return NF_ACCEPT; |
5625 | |
5626 | secmark_active = selinux_secmark_enabled(); |
5627 | peerlbl_active = selinux_peerlbl_enabled(); |
5628 | if (!secmark_active && !peerlbl_active) |
5629 | return NF_ACCEPT; |
5630 | |
5631 | family = state->pf; |
5632 | if (selinux_skb_peerlbl_sid(skb, family, sid: &peer_sid) != 0) |
5633 | return NF_DROP; |
5634 | |
5635 | ifindex = state->in->ifindex; |
5636 | ad_net_init_from_iif(ad: &ad, net: &net, ifindex, family); |
5637 | if (selinux_parse_skb(skb, ad: &ad, addrp: &addrp, src: 1, NULL) != 0) |
5638 | return NF_DROP; |
5639 | |
5640 | if (peerlbl_active) { |
5641 | int err; |
5642 | |
5643 | err = selinux_inet_sys_rcv_skb(ns: state->net, ifindex, |
5644 | addrp, family, peer_sid, ad: &ad); |
5645 | if (err) { |
5646 | selinux_netlbl_err(skb, family, err, 1); |
5647 | return NF_DROP; |
5648 | } |
5649 | } |
5650 | |
5651 | if (secmark_active) |
5652 | if (avc_has_perm(peer_sid, skb->secmark, |
5653 | SECCLASS_PACKET, PACKET__FORWARD_IN, &ad)) |
5654 | return NF_DROP; |
5655 | |
5656 | if (netlbl_enabled()) |
5657 | /* we do this in the FORWARD path and not the POST_ROUTING |
5658 | * path because we want to make sure we apply the necessary |
5659 | * labeling before IPsec is applied so we can leverage AH |
5660 | * protection */ |
5661 | if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0) |
5662 | return NF_DROP; |
5663 | |
5664 | return NF_ACCEPT; |
5665 | } |
5666 | |
5667 | static unsigned int selinux_ip_output(void *priv, struct sk_buff *skb, |
5668 | const struct nf_hook_state *state) |
5669 | { |
5670 | struct sock *sk; |
5671 | u32 sid; |
5672 | |
5673 | if (!netlbl_enabled()) |
5674 | return NF_ACCEPT; |
5675 | |
5676 | /* we do this in the LOCAL_OUT path and not the POST_ROUTING path |
5677 | * because we want to make sure we apply the necessary labeling |
5678 | * before IPsec is applied so we can leverage AH protection */ |
5679 | sk = skb->sk; |
5680 | if (sk) { |
5681 | struct sk_security_struct *sksec; |
5682 | |
5683 | if (sk_listener(sk)) |
5684 | /* if the socket is the listening state then this |
5685 | * packet is a SYN-ACK packet which means it needs to |
5686 | * be labeled based on the connection/request_sock and |
5687 | * not the parent socket. unfortunately, we can't |
5688 | * lookup the request_sock yet as it isn't queued on |
5689 | * the parent socket until after the SYN-ACK is sent. |
5690 | * the "solution" is to simply pass the packet as-is |
5691 | * as any IP option based labeling should be copied |
5692 | * from the initial connection request (in the IP |
5693 | * layer). it is far from ideal, but until we get a |
5694 | * security label in the packet itself this is the |
5695 | * best we can do. */ |
5696 | return NF_ACCEPT; |
5697 | |
5698 | /* standard practice, label using the parent socket */ |
5699 | sksec = sk->sk_security; |
5700 | sid = sksec->sid; |
5701 | } else |
5702 | sid = SECINITSID_KERNEL; |
5703 | if (selinux_netlbl_skbuff_setsid(skb, state->pf, sid) != 0) |
5704 | return NF_DROP; |
5705 | |
5706 | return NF_ACCEPT; |
5707 | } |
5708 | |
5709 | |
5710 | static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb, |
5711 | const struct nf_hook_state *state) |
5712 | { |
5713 | struct sock *sk; |
5714 | struct sk_security_struct *sksec; |
5715 | struct common_audit_data ad; |
5716 | struct lsm_network_audit net; |
5717 | u8 proto = 0; |
5718 | |
5719 | sk = skb_to_full_sk(skb); |
5720 | if (sk == NULL) |
5721 | return NF_ACCEPT; |
5722 | sksec = sk->sk_security; |
5723 | |
5724 | ad_net_init_from_iif(ad: &ad, net: &net, ifindex: state->out->ifindex, family: state->pf); |
5725 | if (selinux_parse_skb(skb, ad: &ad, NULL, src: 0, proto: &proto)) |
5726 | return NF_DROP; |
5727 | |
5728 | if (selinux_secmark_enabled()) |
5729 | if (avc_has_perm(sksec->sid, skb->secmark, |
5730 | SECCLASS_PACKET, PACKET__SEND, &ad)) |
5731 | return NF_DROP_ERR(-ECONNREFUSED); |
5732 | |
5733 | if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto)) |
5734 | return NF_DROP_ERR(-ECONNREFUSED); |
5735 | |
5736 | return NF_ACCEPT; |
5737 | } |
5738 | |
5739 | static unsigned int selinux_ip_postroute(void *priv, |
5740 | struct sk_buff *skb, |
5741 | const struct nf_hook_state *state) |
5742 | { |
5743 | u16 family; |
5744 | u32 secmark_perm; |
5745 | u32 peer_sid; |
5746 | int ifindex; |
5747 | struct sock *sk; |
5748 | struct common_audit_data ad; |
5749 | struct lsm_network_audit net; |
5750 | char *addrp; |
5751 | int secmark_active, peerlbl_active; |
5752 | |
5753 | /* If any sort of compatibility mode is enabled then handoff processing |
5754 | * to the selinux_ip_postroute_compat() function to deal with the |
5755 | * special handling. We do this in an attempt to keep this function |
5756 | * as fast and as clean as possible. */ |
5757 | if (!selinux_policycap_netpeer()) |
5758 | return selinux_ip_postroute_compat(skb, state); |
5759 | |
5760 | secmark_active = selinux_secmark_enabled(); |
5761 | peerlbl_active = selinux_peerlbl_enabled(); |
5762 | if (!secmark_active && !peerlbl_active) |
5763 | return NF_ACCEPT; |
5764 | |
5765 | sk = skb_to_full_sk(skb); |
5766 | |
5767 | #ifdef CONFIG_XFRM |
5768 | /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec |
5769 | * packet transformation so allow the packet to pass without any checks |
5770 | * since we'll have another chance to perform access control checks |
5771 | * when the packet is on it's final way out. |
5772 | * NOTE: there appear to be some IPv6 multicast cases where skb->dst |
5773 | * is NULL, in this case go ahead and apply access control. |
5774 | * NOTE: if this is a local socket (skb->sk != NULL) that is in the |
5775 | * TCP listening state we cannot wait until the XFRM processing |
5776 | * is done as we will miss out on the SA label if we do; |
5777 | * unfortunately, this means more work, but it is only once per |
5778 | * connection. */ |
5779 | if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL && |
5780 | !(sk && sk_listener(sk))) |
5781 | return NF_ACCEPT; |
5782 | #endif |
5783 | |
5784 | family = state->pf; |
5785 | if (sk == NULL) { |
5786 | /* Without an associated socket the packet is either coming |
5787 | * from the kernel or it is being forwarded; check the packet |
5788 | * to determine which and if the packet is being forwarded |
5789 | * query the packet directly to determine the security label. */ |
5790 | if (skb->skb_iif) { |
5791 | secmark_perm = PACKET__FORWARD_OUT; |
5792 | if (selinux_skb_peerlbl_sid(skb, family, sid: &peer_sid)) |
5793 | return NF_DROP; |
5794 | } else { |
5795 | secmark_perm = PACKET__SEND; |
5796 | peer_sid = SECINITSID_KERNEL; |
5797 | } |
5798 | } else if (sk_listener(sk)) { |
5799 | /* Locally generated packet but the associated socket is in the |
5800 | * listening state which means this is a SYN-ACK packet. In |
5801 | * this particular case the correct security label is assigned |
5802 | * to the connection/request_sock but unfortunately we can't |
5803 | * query the request_sock as it isn't queued on the parent |
5804 | * socket until after the SYN-ACK packet is sent; the only |
5805 | * viable choice is to regenerate the label like we do in |
5806 | * selinux_inet_conn_request(). See also selinux_ip_output() |
5807 | * for similar problems. */ |
5808 | u32 skb_sid; |
5809 | struct sk_security_struct *sksec; |
5810 | |
5811 | sksec = sk->sk_security; |
5812 | if (selinux_skb_peerlbl_sid(skb, family, sid: &skb_sid)) |
5813 | return NF_DROP; |
5814 | /* At this point, if the returned skb peerlbl is SECSID_NULL |
5815 | * and the packet has been through at least one XFRM |
5816 | * transformation then we must be dealing with the "final" |
5817 | * form of labeled IPsec packet; since we've already applied |
5818 | * all of our access controls on this packet we can safely |
5819 | * pass the packet. */ |
5820 | if (skb_sid == SECSID_NULL) { |
5821 | switch (family) { |
5822 | case PF_INET: |
5823 | if (IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED) |
5824 | return NF_ACCEPT; |
5825 | break; |
5826 | case PF_INET6: |
5827 | if (IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED) |
5828 | return NF_ACCEPT; |
5829 | break; |
5830 | default: |
5831 | return NF_DROP_ERR(-ECONNREFUSED); |
5832 | } |
5833 | } |
5834 | if (selinux_conn_sid(sk_sid: sksec->sid, skb_sid, conn_sid: &peer_sid)) |
5835 | return NF_DROP; |
5836 | secmark_perm = PACKET__SEND; |
5837 | } else { |
5838 | /* Locally generated packet, fetch the security label from the |
5839 | * associated socket. */ |
5840 | struct sk_security_struct *sksec = sk->sk_security; |
5841 | peer_sid = sksec->sid; |
5842 | secmark_perm = PACKET__SEND; |
5843 | } |
5844 | |
5845 | ifindex = state->out->ifindex; |
5846 | ad_net_init_from_iif(ad: &ad, net: &net, ifindex, family); |
5847 | if (selinux_parse_skb(skb, ad: &ad, addrp: &addrp, src: 0, NULL)) |
5848 | return NF_DROP; |
5849 | |
5850 | if (secmark_active) |
5851 | if (avc_has_perm(peer_sid, skb->secmark, |
5852 | SECCLASS_PACKET, secmark_perm, &ad)) |
5853 | return NF_DROP_ERR(-ECONNREFUSED); |
5854 | |
5855 | if (peerlbl_active) { |
5856 | u32 if_sid; |
5857 | u32 node_sid; |
5858 | |
5859 | if (sel_netif_sid(state->net, ifindex, &if_sid)) |
5860 | return NF_DROP; |
5861 | if (avc_has_perm(peer_sid, if_sid, |
5862 | SECCLASS_NETIF, NETIF__EGRESS, &ad)) |
5863 | return NF_DROP_ERR(-ECONNREFUSED); |
5864 | |
5865 | if (sel_netnode_sid(addrp, family, &node_sid)) |
5866 | return NF_DROP; |
5867 | if (avc_has_perm(peer_sid, node_sid, |
5868 | SECCLASS_NODE, NODE__SENDTO, &ad)) |
5869 | return NF_DROP_ERR(-ECONNREFUSED); |
5870 | } |
5871 | |
5872 | return NF_ACCEPT; |
5873 | } |
5874 | #endif /* CONFIG_NETFILTER */ |
5875 | |
5876 | static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb) |
5877 | { |
5878 | int rc = 0; |
5879 | unsigned int msg_len; |
5880 | unsigned int data_len = skb->len; |
5881 | unsigned char *data = skb->data; |
5882 | struct nlmsghdr *nlh; |
5883 | struct sk_security_struct *sksec = sk->sk_security; |
5884 | u16 sclass = sksec->sclass; |
5885 | u32 perm; |
5886 | |
5887 | while (data_len >= nlmsg_total_size(payload: 0)) { |
5888 | nlh = (struct nlmsghdr *)data; |
5889 | |
5890 | /* NOTE: the nlmsg_len field isn't reliably set by some netlink |
5891 | * users which means we can't reject skb's with bogus |
5892 | * length fields; our solution is to follow what |
5893 | * netlink_rcv_skb() does and simply skip processing at |
5894 | * messages with length fields that are clearly junk |
5895 | */ |
5896 | if (nlh->nlmsg_len < NLMSG_HDRLEN || nlh->nlmsg_len > data_len) |
5897 | return 0; |
5898 | |
5899 | rc = selinux_nlmsg_lookup(sclass, nlh->nlmsg_type, &perm); |
5900 | if (rc == 0) { |
5901 | rc = sock_has_perm(sk, perms: perm); |
5902 | if (rc) |
5903 | return rc; |
5904 | } else if (rc == -EINVAL) { |
5905 | /* -EINVAL is a missing msg/perm mapping */ |
5906 | pr_warn_ratelimited("SELinux: unrecognized netlink" |
5907 | " message: protocol=%hu nlmsg_type=%hu sclass=%s" |
5908 | " pid=%d comm=%s\n" , |
5909 | sk->sk_protocol, nlh->nlmsg_type, |
5910 | secclass_map[sclass - 1].name, |
5911 | task_pid_nr(current), current->comm); |
5912 | if (enforcing_enabled() && |
5913 | !security_get_allow_unknown()) |
5914 | return rc; |
5915 | rc = 0; |
5916 | } else if (rc == -ENOENT) { |
5917 | /* -ENOENT is a missing socket/class mapping, ignore */ |
5918 | rc = 0; |
5919 | } else { |
5920 | return rc; |
5921 | } |
5922 | |
5923 | /* move to the next message after applying netlink padding */ |
5924 | msg_len = NLMSG_ALIGN(nlh->nlmsg_len); |
5925 | if (msg_len >= data_len) |
5926 | return 0; |
5927 | data_len -= msg_len; |
5928 | data += msg_len; |
5929 | } |
5930 | |
5931 | return rc; |
5932 | } |
5933 | |
5934 | static void ipc_init_security(struct ipc_security_struct *isec, u16 sclass) |
5935 | { |
5936 | isec->sclass = sclass; |
5937 | isec->sid = current_sid(); |
5938 | } |
5939 | |
5940 | static int ipc_has_perm(struct kern_ipc_perm *ipc_perms, |
5941 | u32 perms) |
5942 | { |
5943 | struct ipc_security_struct *isec; |
5944 | struct common_audit_data ad; |
5945 | u32 sid = current_sid(); |
5946 | |
5947 | isec = selinux_ipc(ipc_perms); |
5948 | |
5949 | ad.type = LSM_AUDIT_DATA_IPC; |
5950 | ad.u.ipc_id = ipc_perms->key; |
5951 | |
5952 | return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad); |
5953 | } |
5954 | |
5955 | static int selinux_msg_msg_alloc_security(struct msg_msg *msg) |
5956 | { |
5957 | struct msg_security_struct *msec; |
5958 | |
5959 | msec = selinux_msg_msg(msg); |
5960 | msec->sid = SECINITSID_UNLABELED; |
5961 | |
5962 | return 0; |
5963 | } |
5964 | |
5965 | /* message queue security operations */ |
5966 | static int selinux_msg_queue_alloc_security(struct kern_ipc_perm *msq) |
5967 | { |
5968 | struct ipc_security_struct *isec; |
5969 | struct common_audit_data ad; |
5970 | u32 sid = current_sid(); |
5971 | |
5972 | isec = selinux_ipc(msq); |
5973 | ipc_init_security(isec, SECCLASS_MSGQ); |
5974 | |
5975 | ad.type = LSM_AUDIT_DATA_IPC; |
5976 | ad.u.ipc_id = msq->key; |
5977 | |
5978 | return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ, |
5979 | MSGQ__CREATE, &ad); |
5980 | } |
5981 | |
5982 | static int selinux_msg_queue_associate(struct kern_ipc_perm *msq, int msqflg) |
5983 | { |
5984 | struct ipc_security_struct *isec; |
5985 | struct common_audit_data ad; |
5986 | u32 sid = current_sid(); |
5987 | |
5988 | isec = selinux_ipc(msq); |
5989 | |
5990 | ad.type = LSM_AUDIT_DATA_IPC; |
5991 | ad.u.ipc_id = msq->key; |
5992 | |
5993 | return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ, |
5994 | MSGQ__ASSOCIATE, &ad); |
5995 | } |
5996 | |
5997 | static int selinux_msg_queue_msgctl(struct kern_ipc_perm *msq, int cmd) |
5998 | { |
5999 | u32 perms; |
6000 | |
6001 | switch (cmd) { |
6002 | case IPC_INFO: |
6003 | case MSG_INFO: |
6004 | /* No specific object, just general system-wide information. */ |
6005 | return avc_has_perm(current_sid(), SECINITSID_KERNEL, |
6006 | SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL); |
6007 | case IPC_STAT: |
6008 | case MSG_STAT: |
6009 | case MSG_STAT_ANY: |
6010 | perms = MSGQ__GETATTR | MSGQ__ASSOCIATE; |
6011 | break; |
6012 | case IPC_SET: |
6013 | perms = MSGQ__SETATTR; |
6014 | break; |
6015 | case IPC_RMID: |
6016 | perms = MSGQ__DESTROY; |
6017 | break; |
6018 | default: |
6019 | return 0; |
6020 | } |
6021 | |
6022 | return ipc_has_perm(ipc_perms: msq, perms); |
6023 | } |
6024 | |
6025 | static int selinux_msg_queue_msgsnd(struct kern_ipc_perm *msq, struct msg_msg *msg, int msqflg) |
6026 | { |
6027 | struct ipc_security_struct *isec; |
6028 | struct msg_security_struct *msec; |
6029 | struct common_audit_data ad; |
6030 | u32 sid = current_sid(); |
6031 | int rc; |
6032 | |
6033 | isec = selinux_ipc(msq); |
6034 | msec = selinux_msg_msg(msg); |
6035 | |
6036 | /* |
6037 | * First time through, need to assign label to the message |
6038 | */ |
6039 | if (msec->sid == SECINITSID_UNLABELED) { |
6040 | /* |
6041 | * Compute new sid based on current process and |
6042 | * message queue this message will be stored in |
6043 | */ |
6044 | rc = security_transition_sid(sid, isec->sid, |
6045 | SECCLASS_MSG, NULL, &msec->sid); |
6046 | if (rc) |
6047 | return rc; |
6048 | } |
6049 | |
6050 | ad.type = LSM_AUDIT_DATA_IPC; |
6051 | ad.u.ipc_id = msq->key; |
6052 | |
6053 | /* Can this process write to the queue? */ |
6054 | rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ, |
6055 | MSGQ__WRITE, &ad); |
6056 | if (!rc) |
6057 | /* Can this process send the message */ |
6058 | rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG, |
6059 | MSG__SEND, &ad); |
6060 | if (!rc) |
6061 | /* Can the message be put in the queue? */ |
6062 | rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ, |
6063 | MSGQ__ENQUEUE, &ad); |
6064 | |
6065 | return rc; |
6066 | } |
6067 | |
6068 | static int selinux_msg_queue_msgrcv(struct kern_ipc_perm *msq, struct msg_msg *msg, |
6069 | struct task_struct *target, |
6070 | long type, int mode) |
6071 | { |
6072 | struct ipc_security_struct *isec; |
6073 | struct msg_security_struct *msec; |
6074 | struct common_audit_data ad; |
6075 | u32 sid = task_sid_obj(task: target); |
6076 | int rc; |
6077 | |
6078 | isec = selinux_ipc(msq); |
6079 | msec = selinux_msg_msg(msg); |
6080 | |
6081 | ad.type = LSM_AUDIT_DATA_IPC; |
6082 | ad.u.ipc_id = msq->key; |
6083 | |
6084 | rc = avc_has_perm(sid, isec->sid, |
6085 | SECCLASS_MSGQ, MSGQ__READ, &ad); |
6086 | if (!rc) |
6087 | rc = avc_has_perm(sid, msec->sid, |
6088 | SECCLASS_MSG, MSG__RECEIVE, &ad); |
6089 | return rc; |
6090 | } |
6091 | |
6092 | /* Shared Memory security operations */ |
6093 | static int selinux_shm_alloc_security(struct kern_ipc_perm *shp) |
6094 | { |
6095 | struct ipc_security_struct *isec; |
6096 | struct common_audit_data ad; |
6097 | u32 sid = current_sid(); |
6098 | |
6099 | isec = selinux_ipc(shp); |
6100 | ipc_init_security(isec, SECCLASS_SHM); |
6101 | |
6102 | ad.type = LSM_AUDIT_DATA_IPC; |
6103 | ad.u.ipc_id = shp->key; |
6104 | |
6105 | return avc_has_perm(sid, isec->sid, SECCLASS_SHM, |
6106 | SHM__CREATE, &ad); |
6107 | } |
6108 | |
6109 | static int selinux_shm_associate(struct kern_ipc_perm *shp, int shmflg) |
6110 | { |
6111 | struct ipc_security_struct *isec; |
6112 | struct common_audit_data ad; |
6113 | u32 sid = current_sid(); |
6114 | |
6115 | isec = selinux_ipc(shp); |
6116 | |
6117 | ad.type = LSM_AUDIT_DATA_IPC; |
6118 | ad.u.ipc_id = shp->key; |
6119 | |
6120 | return avc_has_perm(sid, isec->sid, SECCLASS_SHM, |
6121 | SHM__ASSOCIATE, &ad); |
6122 | } |
6123 | |
6124 | /* Note, at this point, shp is locked down */ |
6125 | static int selinux_shm_shmctl(struct kern_ipc_perm *shp, int cmd) |
6126 | { |
6127 | u32 perms; |
6128 | |
6129 | switch (cmd) { |
6130 | case IPC_INFO: |
6131 | case SHM_INFO: |
6132 | /* No specific object, just general system-wide information. */ |
6133 | return avc_has_perm(current_sid(), SECINITSID_KERNEL, |
6134 | SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL); |
6135 | case IPC_STAT: |
6136 | case SHM_STAT: |
6137 | case SHM_STAT_ANY: |
6138 | perms = SHM__GETATTR | SHM__ASSOCIATE; |
6139 | break; |
6140 | case IPC_SET: |
6141 | perms = SHM__SETATTR; |
6142 | break; |
6143 | case SHM_LOCK: |
6144 | case SHM_UNLOCK: |
6145 | perms = SHM__LOCK; |
6146 | break; |
6147 | case IPC_RMID: |
6148 | perms = SHM__DESTROY; |
6149 | break; |
6150 | default: |
6151 | return 0; |
6152 | } |
6153 | |
6154 | return ipc_has_perm(ipc_perms: shp, perms); |
6155 | } |
6156 | |
6157 | static int selinux_shm_shmat(struct kern_ipc_perm *shp, |
6158 | char __user *shmaddr, int shmflg) |
6159 | { |
6160 | u32 perms; |
6161 | |
6162 | if (shmflg & SHM_RDONLY) |
6163 | perms = SHM__READ; |
6164 | else |
6165 | perms = SHM__READ | SHM__WRITE; |
6166 | |
6167 | return ipc_has_perm(ipc_perms: shp, perms); |
6168 | } |
6169 | |
6170 | /* Semaphore security operations */ |
6171 | static int selinux_sem_alloc_security(struct kern_ipc_perm *sma) |
6172 | { |
6173 | struct ipc_security_struct *isec; |
6174 | struct common_audit_data ad; |
6175 | u32 sid = current_sid(); |
6176 | |
6177 | isec = selinux_ipc(sma); |
6178 | ipc_init_security(isec, SECCLASS_SEM); |
6179 | |
6180 | ad.type = LSM_AUDIT_DATA_IPC; |
6181 | ad.u.ipc_id = sma->key; |
6182 | |
6183 | return avc_has_perm(sid, isec->sid, SECCLASS_SEM, |
6184 | SEM__CREATE, &ad); |
6185 | } |
6186 | |
6187 | static int selinux_sem_associate(struct kern_ipc_perm *sma, int semflg) |
6188 | { |
6189 | struct ipc_security_struct *isec; |
6190 | struct common_audit_data ad; |
6191 | u32 sid = current_sid(); |
6192 | |
6193 | isec = selinux_ipc(sma); |
6194 | |
6195 | ad.type = LSM_AUDIT_DATA_IPC; |
6196 | ad.u.ipc_id = sma->key; |
6197 | |
6198 | return avc_has_perm(sid, isec->sid, SECCLASS_SEM, |
6199 | SEM__ASSOCIATE, &ad); |
6200 | } |
6201 | |
6202 | /* Note, at this point, sma is locked down */ |
6203 | static int selinux_sem_semctl(struct kern_ipc_perm *sma, int cmd) |
6204 | { |
6205 | int err; |
6206 | u32 perms; |
6207 | |
6208 | switch (cmd) { |
6209 | case IPC_INFO: |
6210 | case SEM_INFO: |
6211 | /* No specific object, just general system-wide information. */ |
6212 | return avc_has_perm(current_sid(), SECINITSID_KERNEL, |
6213 | SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL); |
6214 | case GETPID: |
6215 | case GETNCNT: |
6216 | case GETZCNT: |
6217 | perms = SEM__GETATTR; |
6218 | break; |
6219 | case GETVAL: |
6220 | case GETALL: |
6221 | perms = SEM__READ; |
6222 | break; |
6223 | case SETVAL: |
6224 | case SETALL: |
6225 | perms = SEM__WRITE; |
6226 | break; |
6227 | case IPC_RMID: |
6228 | perms = SEM__DESTROY; |
6229 | break; |
6230 | case IPC_SET: |
6231 | perms = SEM__SETATTR; |
6232 | break; |
6233 | case IPC_STAT: |
6234 | case SEM_STAT: |
6235 | case SEM_STAT_ANY: |
6236 | perms = SEM__GETATTR | SEM__ASSOCIATE; |
6237 | break; |
6238 | default: |
6239 | return 0; |
6240 | } |
6241 | |
6242 | err = ipc_has_perm(ipc_perms: sma, perms); |
6243 | return err; |
6244 | } |
6245 | |
6246 | static int selinux_sem_semop(struct kern_ipc_perm *sma, |
6247 | struct sembuf *sops, unsigned nsops, int alter) |
6248 | { |
6249 | u32 perms; |
6250 | |
6251 | if (alter) |
6252 | perms = SEM__READ | SEM__WRITE; |
6253 | else |
6254 | perms = SEM__READ; |
6255 | |
6256 | return ipc_has_perm(ipc_perms: sma, perms); |
6257 | } |
6258 | |
6259 | static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag) |
6260 | { |
6261 | u32 av = 0; |
6262 | |
6263 | av = 0; |
6264 | if (flag & S_IRUGO) |
6265 | av |= IPC__UNIX_READ; |
6266 | if (flag & S_IWUGO) |
6267 | av |= IPC__UNIX_WRITE; |
6268 | |
6269 | if (av == 0) |
6270 | return 0; |
6271 | |
6272 | return ipc_has_perm(ipc_perms: ipcp, perms: av); |
6273 | } |
6274 | |
6275 | static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid) |
6276 | { |
6277 | struct ipc_security_struct *isec = selinux_ipc(ipcp); |
6278 | *secid = isec->sid; |
6279 | } |
6280 | |
6281 | static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode) |
6282 | { |
6283 | if (inode) |
6284 | inode_doinit_with_dentry(inode, opt_dentry: dentry); |
6285 | } |
6286 | |
6287 | static int selinux_getprocattr(struct task_struct *p, |
6288 | const char *name, char **value) |
6289 | { |
6290 | const struct task_security_struct *__tsec; |
6291 | u32 sid; |
6292 | int error; |
6293 | unsigned len; |
6294 | |
6295 | rcu_read_lock(); |
6296 | __tsec = selinux_cred(__task_cred(p)); |
6297 | |
6298 | if (current != p) { |
6299 | error = avc_has_perm(current_sid(), __tsec->sid, |
6300 | SECCLASS_PROCESS, PROCESS__GETATTR, NULL); |
6301 | if (error) |
6302 | goto bad; |
6303 | } |
6304 | |
6305 | if (!strcmp(name, "current" )) |
6306 | sid = __tsec->sid; |
6307 | else if (!strcmp(name, "prev" )) |
6308 | sid = __tsec->osid; |
6309 | else if (!strcmp(name, "exec" )) |
6310 | sid = __tsec->exec_sid; |
6311 | else if (!strcmp(name, "fscreate" )) |
6312 | sid = __tsec->create_sid; |
6313 | else if (!strcmp(name, "keycreate" )) |
6314 | sid = __tsec->keycreate_sid; |
6315 | else if (!strcmp(name, "sockcreate" )) |
6316 | sid = __tsec->sockcreate_sid; |
6317 | else { |
6318 | error = -EINVAL; |
6319 | goto bad; |
6320 | } |
6321 | rcu_read_unlock(); |
6322 | |
6323 | if (!sid) |
6324 | return 0; |
6325 | |
6326 | error = security_sid_to_context(sid, value, &len); |
6327 | if (error) |
6328 | return error; |
6329 | return len; |
6330 | |
6331 | bad: |
6332 | rcu_read_unlock(); |
6333 | return error; |
6334 | } |
6335 | |
6336 | static int selinux_setprocattr(const char *name, void *value, size_t size) |
6337 | { |
6338 | struct task_security_struct *tsec; |
6339 | struct cred *new; |
6340 | u32 mysid = current_sid(), sid = 0, ptsid; |
6341 | int error; |
6342 | char *str = value; |
6343 | |
6344 | /* |
6345 | * Basic control over ability to set these attributes at all. |
6346 | */ |
6347 | if (!strcmp(name, "exec" )) |
6348 | error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS, |
6349 | PROCESS__SETEXEC, NULL); |
6350 | else if (!strcmp(name, "fscreate" )) |
6351 | error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS, |
6352 | PROCESS__SETFSCREATE, NULL); |
6353 | else if (!strcmp(name, "keycreate" )) |
6354 | error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS, |
6355 | PROCESS__SETKEYCREATE, NULL); |
6356 | else if (!strcmp(name, "sockcreate" )) |
6357 | error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS, |
6358 | PROCESS__SETSOCKCREATE, NULL); |
6359 | else if (!strcmp(name, "current" )) |
6360 | error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS, |
6361 | PROCESS__SETCURRENT, NULL); |
6362 | else |
6363 | error = -EINVAL; |
6364 | if (error) |
6365 | return error; |
6366 | |
6367 | /* Obtain a SID for the context, if one was specified. */ |
6368 | if (size && str[0] && str[0] != '\n') { |
6369 | if (str[size-1] == '\n') { |
6370 | str[size-1] = 0; |
6371 | size--; |
6372 | } |
6373 | error = security_context_to_sid(value, size, |
6374 | &sid, GFP_KERNEL); |
6375 | if (error == -EINVAL && !strcmp(name, "fscreate" )) { |
6376 | if (!has_cap_mac_admin(audit: true)) { |
6377 | struct audit_buffer *ab; |
6378 | size_t audit_size; |
6379 | |
6380 | /* We strip a nul only if it is at the end, otherwise the |
6381 | * context contains a nul and we should audit that */ |
6382 | if (str[size - 1] == '\0') |
6383 | audit_size = size - 1; |
6384 | else |
6385 | audit_size = size; |
6386 | ab = audit_log_start(ctx: audit_context(), |
6387 | GFP_ATOMIC, |
6388 | AUDIT_SELINUX_ERR); |
6389 | if (!ab) |
6390 | return error; |
6391 | audit_log_format(ab, fmt: "op=fscreate invalid_context=" ); |
6392 | audit_log_n_untrustedstring(ab, string: value, n: audit_size); |
6393 | audit_log_end(ab); |
6394 | |
6395 | return error; |
6396 | } |
6397 | error = security_context_to_sid_force(value, size, |
6398 | &sid); |
6399 | } |
6400 | if (error) |
6401 | return error; |
6402 | } |
6403 | |
6404 | new = prepare_creds(); |
6405 | if (!new) |
6406 | return -ENOMEM; |
6407 | |
6408 | /* Permission checking based on the specified context is |
6409 | performed during the actual operation (execve, |
6410 | open/mkdir/...), when we know the full context of the |
6411 | operation. See selinux_bprm_creds_for_exec for the execve |
6412 | checks and may_create for the file creation checks. The |
6413 | operation will then fail if the context is not permitted. */ |
6414 | tsec = selinux_cred(new); |
6415 | if (!strcmp(name, "exec" )) { |
6416 | tsec->exec_sid = sid; |
6417 | } else if (!strcmp(name, "fscreate" )) { |
6418 | tsec->create_sid = sid; |
6419 | } else if (!strcmp(name, "keycreate" )) { |
6420 | if (sid) { |
6421 | error = avc_has_perm(mysid, sid, |
6422 | SECCLASS_KEY, KEY__CREATE, NULL); |
6423 | if (error) |
6424 | goto abort_change; |
6425 | } |
6426 | tsec->keycreate_sid = sid; |
6427 | } else if (!strcmp(name, "sockcreate" )) { |
6428 | tsec->sockcreate_sid = sid; |
6429 | } else if (!strcmp(name, "current" )) { |
6430 | error = -EINVAL; |
6431 | if (sid == 0) |
6432 | goto abort_change; |
6433 | |
6434 | /* Only allow single threaded processes to change context */ |
6435 | if (!current_is_single_threaded()) { |
6436 | error = security_bounded_transition(tsec->sid, sid); |
6437 | if (error) |
6438 | goto abort_change; |
6439 | } |
6440 | |
6441 | /* Check permissions for the transition. */ |
6442 | error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS, |
6443 | PROCESS__DYNTRANSITION, NULL); |
6444 | if (error) |
6445 | goto abort_change; |
6446 | |
6447 | /* Check for ptracing, and update the task SID if ok. |
6448 | Otherwise, leave SID unchanged and fail. */ |
6449 | ptsid = ptrace_parent_sid(); |
6450 | if (ptsid != 0) { |
6451 | error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS, |
6452 | PROCESS__PTRACE, NULL); |
6453 | if (error) |
6454 | goto abort_change; |
6455 | } |
6456 | |
6457 | tsec->sid = sid; |
6458 | } else { |
6459 | error = -EINVAL; |
6460 | goto abort_change; |
6461 | } |
6462 | |
6463 | commit_creds(new); |
6464 | return size; |
6465 | |
6466 | abort_change: |
6467 | abort_creds(new); |
6468 | return error; |
6469 | } |
6470 | |
6471 | static int selinux_ismaclabel(const char *name) |
6472 | { |
6473 | return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0); |
6474 | } |
6475 | |
6476 | static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen) |
6477 | { |
6478 | return security_sid_to_context(secid, |
6479 | secdata, seclen); |
6480 | } |
6481 | |
6482 | static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid) |
6483 | { |
6484 | return security_context_to_sid(secdata, seclen, |
6485 | secid, GFP_KERNEL); |
6486 | } |
6487 | |
6488 | static void selinux_release_secctx(char *secdata, u32 seclen) |
6489 | { |
6490 | kfree(objp: secdata); |
6491 | } |
6492 | |
6493 | static void selinux_inode_invalidate_secctx(struct inode *inode) |
6494 | { |
6495 | struct inode_security_struct *isec = selinux_inode(inode); |
6496 | |
6497 | spin_lock(lock: &isec->lock); |
6498 | isec->initialized = LABEL_INVALID; |
6499 | spin_unlock(lock: &isec->lock); |
6500 | } |
6501 | |
6502 | /* |
6503 | * called with inode->i_mutex locked |
6504 | */ |
6505 | static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen) |
6506 | { |
6507 | int rc = selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, |
6508 | value: ctx, size: ctxlen, flags: 0); |
6509 | /* Do not return error when suppressing label (SBLABEL_MNT not set). */ |
6510 | return rc == -EOPNOTSUPP ? 0 : rc; |
6511 | } |
6512 | |
6513 | /* |
6514 | * called with inode->i_mutex locked |
6515 | */ |
6516 | static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen) |
6517 | { |
6518 | return __vfs_setxattr_noperm(&nop_mnt_idmap, dentry, XATTR_NAME_SELINUX, |
6519 | ctx, ctxlen, 0); |
6520 | } |
6521 | |
6522 | static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen) |
6523 | { |
6524 | int len = 0; |
6525 | len = selinux_inode_getsecurity(idmap: &nop_mnt_idmap, inode, |
6526 | XATTR_SELINUX_SUFFIX, buffer: ctx, alloc: true); |
6527 | if (len < 0) |
6528 | return len; |
6529 | *ctxlen = len; |
6530 | return 0; |
6531 | } |
6532 | #ifdef CONFIG_KEYS |
6533 | |
6534 | static int selinux_key_alloc(struct key *k, const struct cred *cred, |
6535 | unsigned long flags) |
6536 | { |
6537 | const struct task_security_struct *tsec; |
6538 | struct key_security_struct *ksec; |
6539 | |
6540 | ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL); |
6541 | if (!ksec) |
6542 | return -ENOMEM; |
6543 | |
6544 | tsec = selinux_cred(cred); |
6545 | if (tsec->keycreate_sid) |
6546 | ksec->sid = tsec->keycreate_sid; |
6547 | else |
6548 | ksec->sid = tsec->sid; |
6549 | |
6550 | k->security = ksec; |
6551 | return 0; |
6552 | } |
6553 | |
6554 | static void selinux_key_free(struct key *k) |
6555 | { |
6556 | struct key_security_struct *ksec = k->security; |
6557 | |
6558 | k->security = NULL; |
6559 | kfree(objp: ksec); |
6560 | } |
6561 | |
6562 | static int selinux_key_permission(key_ref_t key_ref, |
6563 | const struct cred *cred, |
6564 | enum key_need_perm need_perm) |
6565 | { |
6566 | struct key *key; |
6567 | struct key_security_struct *ksec; |
6568 | u32 perm, sid; |
6569 | |
6570 | switch (need_perm) { |
6571 | case KEY_NEED_VIEW: |
6572 | perm = KEY__VIEW; |
6573 | break; |
6574 | case KEY_NEED_READ: |
6575 | perm = KEY__READ; |
6576 | break; |
6577 | case KEY_NEED_WRITE: |
6578 | perm = KEY__WRITE; |
6579 | break; |
6580 | case KEY_NEED_SEARCH: |
6581 | perm = KEY__SEARCH; |
6582 | break; |
6583 | case KEY_NEED_LINK: |
6584 | perm = KEY__LINK; |
6585 | break; |
6586 | case KEY_NEED_SETATTR: |
6587 | perm = KEY__SETATTR; |
6588 | break; |
6589 | case KEY_NEED_UNLINK: |
6590 | case KEY_SYSADMIN_OVERRIDE: |
6591 | case KEY_AUTHTOKEN_OVERRIDE: |
6592 | case KEY_DEFER_PERM_CHECK: |
6593 | return 0; |
6594 | default: |
6595 | WARN_ON(1); |
6596 | return -EPERM; |
6597 | |
6598 | } |
6599 | |
6600 | sid = cred_sid(cred); |
6601 | key = key_ref_to_ptr(key_ref); |
6602 | ksec = key->security; |
6603 | |
6604 | return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL); |
6605 | } |
6606 | |
6607 | static int selinux_key_getsecurity(struct key *key, char **_buffer) |
6608 | { |
6609 | struct key_security_struct *ksec = key->security; |
6610 | char *context = NULL; |
6611 | unsigned len; |
6612 | int rc; |
6613 | |
6614 | rc = security_sid_to_context(ksec->sid, |
6615 | &context, &len); |
6616 | if (!rc) |
6617 | rc = len; |
6618 | *_buffer = context; |
6619 | return rc; |
6620 | } |
6621 | |
6622 | #ifdef CONFIG_KEY_NOTIFICATIONS |
6623 | static int selinux_watch_key(struct key *key) |
6624 | { |
6625 | struct key_security_struct *ksec = key->security; |
6626 | u32 sid = current_sid(); |
6627 | |
6628 | return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, KEY__VIEW, NULL); |
6629 | } |
6630 | #endif |
6631 | #endif |
6632 | |
6633 | #ifdef CONFIG_SECURITY_INFINIBAND |
6634 | static int selinux_ib_pkey_access(void *ib_sec, u64 subnet_prefix, u16 pkey_val) |
6635 | { |
6636 | struct common_audit_data ad; |
6637 | int err; |
6638 | u32 sid = 0; |
6639 | struct ib_security_struct *sec = ib_sec; |
6640 | struct lsm_ibpkey_audit ibpkey; |
6641 | |
6642 | err = sel_ib_pkey_sid(subnet_prefix, pkey_val, &sid); |
6643 | if (err) |
6644 | return err; |
6645 | |
6646 | ad.type = LSM_AUDIT_DATA_IBPKEY; |
6647 | ibpkey.subnet_prefix = subnet_prefix; |
6648 | ibpkey.pkey = pkey_val; |
6649 | ad.u.ibpkey = &ibpkey; |
6650 | return avc_has_perm(sec->sid, sid, |
6651 | SECCLASS_INFINIBAND_PKEY, |
6652 | INFINIBAND_PKEY__ACCESS, &ad); |
6653 | } |
6654 | |
6655 | static int selinux_ib_endport_manage_subnet(void *ib_sec, const char *dev_name, |
6656 | u8 port_num) |
6657 | { |
6658 | struct common_audit_data ad; |
6659 | int err; |
6660 | u32 sid = 0; |
6661 | struct ib_security_struct *sec = ib_sec; |
6662 | struct lsm_ibendport_audit ibendport; |
6663 | |
6664 | err = security_ib_endport_sid(dev_name, port_num, |
6665 | &sid); |
6666 | |
6667 | if (err) |
6668 | return err; |
6669 | |
6670 | ad.type = LSM_AUDIT_DATA_IBENDPORT; |
6671 | ibendport.dev_name = dev_name; |
6672 | ibendport.port = port_num; |
6673 | ad.u.ibendport = &ibendport; |
6674 | return avc_has_perm(sec->sid, sid, |
6675 | SECCLASS_INFINIBAND_ENDPORT, |
6676 | INFINIBAND_ENDPORT__MANAGE_SUBNET, &ad); |
6677 | } |
6678 | |
6679 | static int selinux_ib_alloc_security(void **ib_sec) |
6680 | { |
6681 | struct ib_security_struct *sec; |
6682 | |
6683 | sec = kzalloc(sizeof(*sec), GFP_KERNEL); |
6684 | if (!sec) |
6685 | return -ENOMEM; |
6686 | sec->sid = current_sid(); |
6687 | |
6688 | *ib_sec = sec; |
6689 | return 0; |
6690 | } |
6691 | |
6692 | static void selinux_ib_free_security(void *ib_sec) |
6693 | { |
6694 | kfree(objp: ib_sec); |
6695 | } |
6696 | #endif |
6697 | |
6698 | #ifdef CONFIG_BPF_SYSCALL |
6699 | static int selinux_bpf(int cmd, union bpf_attr *attr, |
6700 | unsigned int size) |
6701 | { |
6702 | u32 sid = current_sid(); |
6703 | int ret; |
6704 | |
6705 | switch (cmd) { |
6706 | case BPF_MAP_CREATE: |
6707 | ret = avc_has_perm(sid, sid, SECCLASS_BPF, BPF__MAP_CREATE, |
6708 | NULL); |
6709 | break; |
6710 | case BPF_PROG_LOAD: |
6711 | ret = avc_has_perm(sid, sid, SECCLASS_BPF, BPF__PROG_LOAD, |
6712 | NULL); |
6713 | break; |
6714 | default: |
6715 | ret = 0; |
6716 | break; |
6717 | } |
6718 | |
6719 | return ret; |
6720 | } |
6721 | |
6722 | static u32 bpf_map_fmode_to_av(fmode_t fmode) |
6723 | { |
6724 | u32 av = 0; |
6725 | |
6726 | if (fmode & FMODE_READ) |
6727 | av |= BPF__MAP_READ; |
6728 | if (fmode & FMODE_WRITE) |
6729 | av |= BPF__MAP_WRITE; |
6730 | return av; |
6731 | } |
6732 | |
6733 | /* This function will check the file pass through unix socket or binder to see |
6734 | * if it is a bpf related object. And apply corresponding checks on the bpf |
6735 | * object based on the type. The bpf maps and programs, not like other files and |
6736 | * socket, are using a shared anonymous inode inside the kernel as their inode. |
6737 | * So checking that inode cannot identify if the process have privilege to |
6738 | * access the bpf object and that's why we have to add this additional check in |
6739 | * selinux_file_receive and selinux_binder_transfer_files. |
6740 | */ |
6741 | static int bpf_fd_pass(const struct file *file, u32 sid) |
6742 | { |
6743 | struct bpf_security_struct *bpfsec; |
6744 | struct bpf_prog *prog; |
6745 | struct bpf_map *map; |
6746 | int ret; |
6747 | |
6748 | if (file->f_op == &bpf_map_fops) { |
6749 | map = file->private_data; |
6750 | bpfsec = map->security; |
6751 | ret = avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF, |
6752 | bpf_map_fmode_to_av(file->f_mode), NULL); |
6753 | if (ret) |
6754 | return ret; |
6755 | } else if (file->f_op == &bpf_prog_fops) { |
6756 | prog = file->private_data; |
6757 | bpfsec = prog->aux->security; |
6758 | ret = avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF, |
6759 | BPF__PROG_RUN, NULL); |
6760 | if (ret) |
6761 | return ret; |
6762 | } |
6763 | return 0; |
6764 | } |
6765 | |
6766 | static int selinux_bpf_map(struct bpf_map *map, fmode_t fmode) |
6767 | { |
6768 | u32 sid = current_sid(); |
6769 | struct bpf_security_struct *bpfsec; |
6770 | |
6771 | bpfsec = map->security; |
6772 | return avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF, |
6773 | bpf_map_fmode_to_av(fmode), NULL); |
6774 | } |
6775 | |
6776 | static int selinux_bpf_prog(struct bpf_prog *prog) |
6777 | { |
6778 | u32 sid = current_sid(); |
6779 | struct bpf_security_struct *bpfsec; |
6780 | |
6781 | bpfsec = prog->aux->security; |
6782 | return avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF, |
6783 | BPF__PROG_RUN, NULL); |
6784 | } |
6785 | |
6786 | static int selinux_bpf_map_alloc(struct bpf_map *map) |
6787 | { |
6788 | struct bpf_security_struct *bpfsec; |
6789 | |
6790 | bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL); |
6791 | if (!bpfsec) |
6792 | return -ENOMEM; |
6793 | |
6794 | bpfsec->sid = current_sid(); |
6795 | map->security = bpfsec; |
6796 | |
6797 | return 0; |
6798 | } |
6799 | |
6800 | static void selinux_bpf_map_free(struct bpf_map *map) |
6801 | { |
6802 | struct bpf_security_struct *bpfsec = map->security; |
6803 | |
6804 | map->security = NULL; |
6805 | kfree(objp: bpfsec); |
6806 | } |
6807 | |
6808 | static int selinux_bpf_prog_alloc(struct bpf_prog_aux *aux) |
6809 | { |
6810 | struct bpf_security_struct *bpfsec; |
6811 | |
6812 | bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL); |
6813 | if (!bpfsec) |
6814 | return -ENOMEM; |
6815 | |
6816 | bpfsec->sid = current_sid(); |
6817 | aux->security = bpfsec; |
6818 | |
6819 | return 0; |
6820 | } |
6821 | |
6822 | static void selinux_bpf_prog_free(struct bpf_prog_aux *aux) |
6823 | { |
6824 | struct bpf_security_struct *bpfsec = aux->security; |
6825 | |
6826 | aux->security = NULL; |
6827 | kfree(objp: bpfsec); |
6828 | } |
6829 | #endif |
6830 | |
6831 | struct lsm_blob_sizes selinux_blob_sizes __ro_after_init = { |
6832 | .lbs_cred = sizeof(struct task_security_struct), |
6833 | .lbs_file = sizeof(struct file_security_struct), |
6834 | .lbs_inode = sizeof(struct inode_security_struct), |
6835 | .lbs_ipc = sizeof(struct ipc_security_struct), |
6836 | .lbs_msg_msg = sizeof(struct msg_security_struct), |
6837 | .lbs_superblock = sizeof(struct superblock_security_struct), |
6838 | .lbs_xattr_count = SELINUX_INODE_INIT_XATTRS, |
6839 | }; |
6840 | |
6841 | #ifdef CONFIG_PERF_EVENTS |
6842 | static int selinux_perf_event_open(struct perf_event_attr *attr, int type) |
6843 | { |
6844 | u32 requested, sid = current_sid(); |
6845 | |
6846 | if (type == PERF_SECURITY_OPEN) |
6847 | requested = PERF_EVENT__OPEN; |
6848 | else if (type == PERF_SECURITY_CPU) |
6849 | requested = PERF_EVENT__CPU; |
6850 | else if (type == PERF_SECURITY_KERNEL) |
6851 | requested = PERF_EVENT__KERNEL; |
6852 | else if (type == PERF_SECURITY_TRACEPOINT) |
6853 | requested = PERF_EVENT__TRACEPOINT; |
6854 | else |
6855 | return -EINVAL; |
6856 | |
6857 | return avc_has_perm(sid, sid, SECCLASS_PERF_EVENT, |
6858 | requested, NULL); |
6859 | } |
6860 | |
6861 | static int selinux_perf_event_alloc(struct perf_event *event) |
6862 | { |
6863 | struct perf_event_security_struct *perfsec; |
6864 | |
6865 | perfsec = kzalloc(sizeof(*perfsec), GFP_KERNEL); |
6866 | if (!perfsec) |
6867 | return -ENOMEM; |
6868 | |
6869 | perfsec->sid = current_sid(); |
6870 | event->security = perfsec; |
6871 | |
6872 | return 0; |
6873 | } |
6874 | |
6875 | static void selinux_perf_event_free(struct perf_event *event) |
6876 | { |
6877 | struct perf_event_security_struct *perfsec = event->security; |
6878 | |
6879 | event->security = NULL; |
6880 | kfree(objp: perfsec); |
6881 | } |
6882 | |
6883 | static int selinux_perf_event_read(struct perf_event *event) |
6884 | { |
6885 | struct perf_event_security_struct *perfsec = event->security; |
6886 | u32 sid = current_sid(); |
6887 | |
6888 | return avc_has_perm(sid, perfsec->sid, |
6889 | SECCLASS_PERF_EVENT, PERF_EVENT__READ, NULL); |
6890 | } |
6891 | |
6892 | static int selinux_perf_event_write(struct perf_event *event) |
6893 | { |
6894 | struct perf_event_security_struct *perfsec = event->security; |
6895 | u32 sid = current_sid(); |
6896 | |
6897 | return avc_has_perm(sid, perfsec->sid, |
6898 | SECCLASS_PERF_EVENT, PERF_EVENT__WRITE, NULL); |
6899 | } |
6900 | #endif |
6901 | |
6902 | #ifdef CONFIG_IO_URING |
6903 | /** |
6904 | * selinux_uring_override_creds - check the requested cred override |
6905 | * @new: the target creds |
6906 | * |
6907 | * Check to see if the current task is allowed to override it's credentials |
6908 | * to service an io_uring operation. |
6909 | */ |
6910 | static int selinux_uring_override_creds(const struct cred *new) |
6911 | { |
6912 | return avc_has_perm(current_sid(), cred_sid(new), |
6913 | SECCLASS_IO_URING, IO_URING__OVERRIDE_CREDS, NULL); |
6914 | } |
6915 | |
6916 | /** |
6917 | * selinux_uring_sqpoll - check if a io_uring polling thread can be created |
6918 | * |
6919 | * Check to see if the current task is allowed to create a new io_uring |
6920 | * kernel polling thread. |
6921 | */ |
6922 | static int selinux_uring_sqpoll(void) |
6923 | { |
6924 | u32 sid = current_sid(); |
6925 | |
6926 | return avc_has_perm(sid, sid, |
6927 | SECCLASS_IO_URING, IO_URING__SQPOLL, NULL); |
6928 | } |
6929 | |
6930 | /** |
6931 | * selinux_uring_cmd - check if IORING_OP_URING_CMD is allowed |
6932 | * @ioucmd: the io_uring command structure |
6933 | * |
6934 | * Check to see if the current domain is allowed to execute an |
6935 | * IORING_OP_URING_CMD against the device/file specified in @ioucmd. |
6936 | * |
6937 | */ |
6938 | static int selinux_uring_cmd(struct io_uring_cmd *ioucmd) |
6939 | { |
6940 | struct file *file = ioucmd->file; |
6941 | struct inode *inode = file_inode(f: file); |
6942 | struct inode_security_struct *isec = selinux_inode(inode); |
6943 | struct common_audit_data ad; |
6944 | |
6945 | ad.type = LSM_AUDIT_DATA_FILE; |
6946 | ad.u.file = file; |
6947 | |
6948 | return avc_has_perm(current_sid(), isec->sid, |
6949 | SECCLASS_IO_URING, IO_URING__CMD, &ad); |
6950 | } |
6951 | #endif /* CONFIG_IO_URING */ |
6952 | |
6953 | /* |
6954 | * IMPORTANT NOTE: When adding new hooks, please be careful to keep this order: |
6955 | * 1. any hooks that don't belong to (2.) or (3.) below, |
6956 | * 2. hooks that both access structures allocated by other hooks, and allocate |
6957 | * structures that can be later accessed by other hooks (mostly "cloning" |
6958 | * hooks), |
6959 | * 3. hooks that only allocate structures that can be later accessed by other |
6960 | * hooks ("allocating" hooks). |
6961 | * |
6962 | * Please follow block comment delimiters in the list to keep this order. |
6963 | */ |
6964 | static struct security_hook_list selinux_hooks[] __ro_after_init = { |
6965 | LSM_HOOK_INIT(binder_set_context_mgr, selinux_binder_set_context_mgr), |
6966 | LSM_HOOK_INIT(binder_transaction, selinux_binder_transaction), |
6967 | LSM_HOOK_INIT(binder_transfer_binder, selinux_binder_transfer_binder), |
6968 | LSM_HOOK_INIT(binder_transfer_file, selinux_binder_transfer_file), |
6969 | |
6970 | LSM_HOOK_INIT(ptrace_access_check, selinux_ptrace_access_check), |
6971 | LSM_HOOK_INIT(ptrace_traceme, selinux_ptrace_traceme), |
6972 | LSM_HOOK_INIT(capget, selinux_capget), |
6973 | LSM_HOOK_INIT(capset, selinux_capset), |
6974 | LSM_HOOK_INIT(capable, selinux_capable), |
6975 | LSM_HOOK_INIT(quotactl, selinux_quotactl), |
6976 | LSM_HOOK_INIT(quota_on, selinux_quota_on), |
6977 | LSM_HOOK_INIT(syslog, selinux_syslog), |
6978 | LSM_HOOK_INIT(vm_enough_memory, selinux_vm_enough_memory), |
6979 | |
6980 | LSM_HOOK_INIT(netlink_send, selinux_netlink_send), |
6981 | |
6982 | LSM_HOOK_INIT(bprm_creds_for_exec, selinux_bprm_creds_for_exec), |
6983 | LSM_HOOK_INIT(bprm_committing_creds, selinux_bprm_committing_creds), |
6984 | LSM_HOOK_INIT(bprm_committed_creds, selinux_bprm_committed_creds), |
6985 | |
6986 | LSM_HOOK_INIT(sb_free_mnt_opts, selinux_free_mnt_opts), |
6987 | LSM_HOOK_INIT(sb_mnt_opts_compat, selinux_sb_mnt_opts_compat), |
6988 | LSM_HOOK_INIT(sb_remount, selinux_sb_remount), |
6989 | LSM_HOOK_INIT(sb_kern_mount, selinux_sb_kern_mount), |
6990 | LSM_HOOK_INIT(sb_show_options, selinux_sb_show_options), |
6991 | LSM_HOOK_INIT(sb_statfs, selinux_sb_statfs), |
6992 | LSM_HOOK_INIT(sb_mount, selinux_mount), |
6993 | LSM_HOOK_INIT(sb_umount, selinux_umount), |
6994 | LSM_HOOK_INIT(sb_set_mnt_opts, selinux_set_mnt_opts), |
6995 | LSM_HOOK_INIT(sb_clone_mnt_opts, selinux_sb_clone_mnt_opts), |
6996 | |
6997 | LSM_HOOK_INIT(move_mount, selinux_move_mount), |
6998 | |
6999 | LSM_HOOK_INIT(dentry_init_security, selinux_dentry_init_security), |
7000 | LSM_HOOK_INIT(dentry_create_files_as, selinux_dentry_create_files_as), |
7001 | |
7002 | LSM_HOOK_INIT(inode_free_security, selinux_inode_free_security), |
7003 | LSM_HOOK_INIT(inode_init_security, selinux_inode_init_security), |
7004 | LSM_HOOK_INIT(inode_init_security_anon, selinux_inode_init_security_anon), |
7005 | LSM_HOOK_INIT(inode_create, selinux_inode_create), |
7006 | LSM_HOOK_INIT(inode_link, selinux_inode_link), |
7007 | LSM_HOOK_INIT(inode_unlink, selinux_inode_unlink), |
7008 | LSM_HOOK_INIT(inode_symlink, selinux_inode_symlink), |
7009 | LSM_HOOK_INIT(inode_mkdir, selinux_inode_mkdir), |
7010 | LSM_HOOK_INIT(inode_rmdir, selinux_inode_rmdir), |
7011 | LSM_HOOK_INIT(inode_mknod, selinux_inode_mknod), |
7012 | LSM_HOOK_INIT(inode_rename, selinux_inode_rename), |
7013 | LSM_HOOK_INIT(inode_readlink, selinux_inode_readlink), |
7014 | LSM_HOOK_INIT(inode_follow_link, selinux_inode_follow_link), |
7015 | LSM_HOOK_INIT(inode_permission, selinux_inode_permission), |
7016 | LSM_HOOK_INIT(inode_setattr, selinux_inode_setattr), |
7017 | LSM_HOOK_INIT(inode_getattr, selinux_inode_getattr), |
7018 | LSM_HOOK_INIT(inode_setxattr, selinux_inode_setxattr), |
7019 | LSM_HOOK_INIT(inode_post_setxattr, selinux_inode_post_setxattr), |
7020 | LSM_HOOK_INIT(inode_getxattr, selinux_inode_getxattr), |
7021 | LSM_HOOK_INIT(inode_listxattr, selinux_inode_listxattr), |
7022 | LSM_HOOK_INIT(inode_removexattr, selinux_inode_removexattr), |
7023 | LSM_HOOK_INIT(inode_set_acl, selinux_inode_set_acl), |
7024 | LSM_HOOK_INIT(inode_get_acl, selinux_inode_get_acl), |
7025 | LSM_HOOK_INIT(inode_remove_acl, selinux_inode_remove_acl), |
7026 | LSM_HOOK_INIT(inode_getsecurity, selinux_inode_getsecurity), |
7027 | LSM_HOOK_INIT(inode_setsecurity, selinux_inode_setsecurity), |
7028 | LSM_HOOK_INIT(inode_listsecurity, selinux_inode_listsecurity), |
7029 | LSM_HOOK_INIT(inode_getsecid, selinux_inode_getsecid), |
7030 | LSM_HOOK_INIT(inode_copy_up, selinux_inode_copy_up), |
7031 | LSM_HOOK_INIT(inode_copy_up_xattr, selinux_inode_copy_up_xattr), |
7032 | LSM_HOOK_INIT(path_notify, selinux_path_notify), |
7033 | |
7034 | LSM_HOOK_INIT(kernfs_init_security, selinux_kernfs_init_security), |
7035 | |
7036 | LSM_HOOK_INIT(file_permission, selinux_file_permission), |
7037 | LSM_HOOK_INIT(file_alloc_security, selinux_file_alloc_security), |
7038 | LSM_HOOK_INIT(file_ioctl, selinux_file_ioctl), |
7039 | LSM_HOOK_INIT(mmap_file, selinux_mmap_file), |
7040 | LSM_HOOK_INIT(mmap_addr, selinux_mmap_addr), |
7041 | LSM_HOOK_INIT(file_mprotect, selinux_file_mprotect), |
7042 | LSM_HOOK_INIT(file_lock, selinux_file_lock), |
7043 | LSM_HOOK_INIT(file_fcntl, selinux_file_fcntl), |
7044 | LSM_HOOK_INIT(file_set_fowner, selinux_file_set_fowner), |
7045 | LSM_HOOK_INIT(file_send_sigiotask, selinux_file_send_sigiotask), |
7046 | LSM_HOOK_INIT(file_receive, selinux_file_receive), |
7047 | |
7048 | LSM_HOOK_INIT(file_open, selinux_file_open), |
7049 | |
7050 | LSM_HOOK_INIT(task_alloc, selinux_task_alloc), |
7051 | LSM_HOOK_INIT(cred_prepare, selinux_cred_prepare), |
7052 | LSM_HOOK_INIT(cred_transfer, selinux_cred_transfer), |
7053 | LSM_HOOK_INIT(cred_getsecid, selinux_cred_getsecid), |
7054 | LSM_HOOK_INIT(kernel_act_as, selinux_kernel_act_as), |
7055 | LSM_HOOK_INIT(kernel_create_files_as, selinux_kernel_create_files_as), |
7056 | LSM_HOOK_INIT(kernel_module_request, selinux_kernel_module_request), |
7057 | LSM_HOOK_INIT(kernel_load_data, selinux_kernel_load_data), |
7058 | LSM_HOOK_INIT(kernel_read_file, selinux_kernel_read_file), |
7059 | LSM_HOOK_INIT(task_setpgid, selinux_task_setpgid), |
7060 | LSM_HOOK_INIT(task_getpgid, selinux_task_getpgid), |
7061 | LSM_HOOK_INIT(task_getsid, selinux_task_getsid), |
7062 | LSM_HOOK_INIT(current_getsecid_subj, selinux_current_getsecid_subj), |
7063 | LSM_HOOK_INIT(task_getsecid_obj, selinux_task_getsecid_obj), |
7064 | LSM_HOOK_INIT(task_setnice, selinux_task_setnice), |
7065 | LSM_HOOK_INIT(task_setioprio, selinux_task_setioprio), |
7066 | LSM_HOOK_INIT(task_getioprio, selinux_task_getioprio), |
7067 | LSM_HOOK_INIT(task_prlimit, selinux_task_prlimit), |
7068 | LSM_HOOK_INIT(task_setrlimit, selinux_task_setrlimit), |
7069 | LSM_HOOK_INIT(task_setscheduler, selinux_task_setscheduler), |
7070 | LSM_HOOK_INIT(task_getscheduler, selinux_task_getscheduler), |
7071 | LSM_HOOK_INIT(task_movememory, selinux_task_movememory), |
7072 | LSM_HOOK_INIT(task_kill, selinux_task_kill), |
7073 | LSM_HOOK_INIT(task_to_inode, selinux_task_to_inode), |
7074 | LSM_HOOK_INIT(userns_create, selinux_userns_create), |
7075 | |
7076 | LSM_HOOK_INIT(ipc_permission, selinux_ipc_permission), |
7077 | LSM_HOOK_INIT(ipc_getsecid, selinux_ipc_getsecid), |
7078 | |
7079 | LSM_HOOK_INIT(msg_queue_associate, selinux_msg_queue_associate), |
7080 | LSM_HOOK_INIT(msg_queue_msgctl, selinux_msg_queue_msgctl), |
7081 | LSM_HOOK_INIT(msg_queue_msgsnd, selinux_msg_queue_msgsnd), |
7082 | LSM_HOOK_INIT(msg_queue_msgrcv, selinux_msg_queue_msgrcv), |
7083 | |
7084 | LSM_HOOK_INIT(shm_associate, selinux_shm_associate), |
7085 | LSM_HOOK_INIT(shm_shmctl, selinux_shm_shmctl), |
7086 | LSM_HOOK_INIT(shm_shmat, selinux_shm_shmat), |
7087 | |
7088 | LSM_HOOK_INIT(sem_associate, selinux_sem_associate), |
7089 | LSM_HOOK_INIT(sem_semctl, selinux_sem_semctl), |
7090 | LSM_HOOK_INIT(sem_semop, selinux_sem_semop), |
7091 | |
7092 | LSM_HOOK_INIT(d_instantiate, selinux_d_instantiate), |
7093 | |
7094 | LSM_HOOK_INIT(getprocattr, selinux_getprocattr), |
7095 | LSM_HOOK_INIT(setprocattr, selinux_setprocattr), |
7096 | |
7097 | LSM_HOOK_INIT(ismaclabel, selinux_ismaclabel), |
7098 | LSM_HOOK_INIT(secctx_to_secid, selinux_secctx_to_secid), |
7099 | LSM_HOOK_INIT(release_secctx, selinux_release_secctx), |
7100 | LSM_HOOK_INIT(inode_invalidate_secctx, selinux_inode_invalidate_secctx), |
7101 | LSM_HOOK_INIT(inode_notifysecctx, selinux_inode_notifysecctx), |
7102 | LSM_HOOK_INIT(inode_setsecctx, selinux_inode_setsecctx), |
7103 | |
7104 | LSM_HOOK_INIT(unix_stream_connect, selinux_socket_unix_stream_connect), |
7105 | LSM_HOOK_INIT(unix_may_send, selinux_socket_unix_may_send), |
7106 | |
7107 | LSM_HOOK_INIT(socket_create, selinux_socket_create), |
7108 | LSM_HOOK_INIT(socket_post_create, selinux_socket_post_create), |
7109 | LSM_HOOK_INIT(socket_socketpair, selinux_socket_socketpair), |
7110 | LSM_HOOK_INIT(socket_bind, selinux_socket_bind), |
7111 | LSM_HOOK_INIT(socket_connect, selinux_socket_connect), |
7112 | LSM_HOOK_INIT(socket_listen, selinux_socket_listen), |
7113 | LSM_HOOK_INIT(socket_accept, selinux_socket_accept), |
7114 | LSM_HOOK_INIT(socket_sendmsg, selinux_socket_sendmsg), |
7115 | LSM_HOOK_INIT(socket_recvmsg, selinux_socket_recvmsg), |
7116 | LSM_HOOK_INIT(socket_getsockname, selinux_socket_getsockname), |
7117 | LSM_HOOK_INIT(socket_getpeername, selinux_socket_getpeername), |
7118 | LSM_HOOK_INIT(socket_getsockopt, selinux_socket_getsockopt), |
7119 | LSM_HOOK_INIT(socket_setsockopt, selinux_socket_setsockopt), |
7120 | LSM_HOOK_INIT(socket_shutdown, selinux_socket_shutdown), |
7121 | LSM_HOOK_INIT(socket_sock_rcv_skb, selinux_socket_sock_rcv_skb), |
7122 | LSM_HOOK_INIT(socket_getpeersec_stream, |
7123 | selinux_socket_getpeersec_stream), |
7124 | LSM_HOOK_INIT(socket_getpeersec_dgram, selinux_socket_getpeersec_dgram), |
7125 | LSM_HOOK_INIT(sk_free_security, selinux_sk_free_security), |
7126 | LSM_HOOK_INIT(sk_clone_security, selinux_sk_clone_security), |
7127 | LSM_HOOK_INIT(sk_getsecid, selinux_sk_getsecid), |
7128 | LSM_HOOK_INIT(sock_graft, selinux_sock_graft), |
7129 | LSM_HOOK_INIT(sctp_assoc_request, selinux_sctp_assoc_request), |
7130 | LSM_HOOK_INIT(sctp_sk_clone, selinux_sctp_sk_clone), |
7131 | LSM_HOOK_INIT(sctp_bind_connect, selinux_sctp_bind_connect), |
7132 | LSM_HOOK_INIT(sctp_assoc_established, selinux_sctp_assoc_established), |
7133 | LSM_HOOK_INIT(mptcp_add_subflow, selinux_mptcp_add_subflow), |
7134 | LSM_HOOK_INIT(inet_conn_request, selinux_inet_conn_request), |
7135 | LSM_HOOK_INIT(inet_csk_clone, selinux_inet_csk_clone), |
7136 | LSM_HOOK_INIT(inet_conn_established, selinux_inet_conn_established), |
7137 | LSM_HOOK_INIT(secmark_relabel_packet, selinux_secmark_relabel_packet), |
7138 | LSM_HOOK_INIT(secmark_refcount_inc, selinux_secmark_refcount_inc), |
7139 | LSM_HOOK_INIT(secmark_refcount_dec, selinux_secmark_refcount_dec), |
7140 | LSM_HOOK_INIT(req_classify_flow, selinux_req_classify_flow), |
7141 | LSM_HOOK_INIT(tun_dev_free_security, selinux_tun_dev_free_security), |
7142 | LSM_HOOK_INIT(tun_dev_create, selinux_tun_dev_create), |
7143 | LSM_HOOK_INIT(tun_dev_attach_queue, selinux_tun_dev_attach_queue), |
7144 | LSM_HOOK_INIT(tun_dev_attach, selinux_tun_dev_attach), |
7145 | LSM_HOOK_INIT(tun_dev_open, selinux_tun_dev_open), |
7146 | #ifdef CONFIG_SECURITY_INFINIBAND |
7147 | LSM_HOOK_INIT(ib_pkey_access, selinux_ib_pkey_access), |
7148 | LSM_HOOK_INIT(ib_endport_manage_subnet, |
7149 | selinux_ib_endport_manage_subnet), |
7150 | LSM_HOOK_INIT(ib_free_security, selinux_ib_free_security), |
7151 | #endif |
7152 | #ifdef CONFIG_SECURITY_NETWORK_XFRM |
7153 | LSM_HOOK_INIT(xfrm_policy_free_security, selinux_xfrm_policy_free), |
7154 | LSM_HOOK_INIT(xfrm_policy_delete_security, selinux_xfrm_policy_delete), |
7155 | LSM_HOOK_INIT(xfrm_state_free_security, selinux_xfrm_state_free), |
7156 | LSM_HOOK_INIT(xfrm_state_delete_security, selinux_xfrm_state_delete), |
7157 | LSM_HOOK_INIT(xfrm_policy_lookup, selinux_xfrm_policy_lookup), |
7158 | LSM_HOOK_INIT(xfrm_state_pol_flow_match, |
7159 | selinux_xfrm_state_pol_flow_match), |
7160 | LSM_HOOK_INIT(xfrm_decode_session, selinux_xfrm_decode_session), |
7161 | #endif |
7162 | |
7163 | #ifdef CONFIG_KEYS |
7164 | LSM_HOOK_INIT(key_free, selinux_key_free), |
7165 | LSM_HOOK_INIT(key_permission, selinux_key_permission), |
7166 | LSM_HOOK_INIT(key_getsecurity, selinux_key_getsecurity), |
7167 | #ifdef CONFIG_KEY_NOTIFICATIONS |
7168 | LSM_HOOK_INIT(watch_key, selinux_watch_key), |
7169 | #endif |
7170 | #endif |
7171 | |
7172 | #ifdef CONFIG_AUDIT |
7173 | LSM_HOOK_INIT(audit_rule_known, selinux_audit_rule_known), |
7174 | LSM_HOOK_INIT(audit_rule_match, selinux_audit_rule_match), |
7175 | LSM_HOOK_INIT(audit_rule_free, selinux_audit_rule_free), |
7176 | #endif |
7177 | |
7178 | #ifdef CONFIG_BPF_SYSCALL |
7179 | LSM_HOOK_INIT(bpf, selinux_bpf), |
7180 | LSM_HOOK_INIT(bpf_map, selinux_bpf_map), |
7181 | LSM_HOOK_INIT(bpf_prog, selinux_bpf_prog), |
7182 | LSM_HOOK_INIT(bpf_map_free_security, selinux_bpf_map_free), |
7183 | LSM_HOOK_INIT(bpf_prog_free_security, selinux_bpf_prog_free), |
7184 | #endif |
7185 | |
7186 | #ifdef CONFIG_PERF_EVENTS |
7187 | LSM_HOOK_INIT(perf_event_open, selinux_perf_event_open), |
7188 | LSM_HOOK_INIT(perf_event_free, selinux_perf_event_free), |
7189 | LSM_HOOK_INIT(perf_event_read, selinux_perf_event_read), |
7190 | LSM_HOOK_INIT(perf_event_write, selinux_perf_event_write), |
7191 | #endif |
7192 | |
7193 | #ifdef CONFIG_IO_URING |
7194 | LSM_HOOK_INIT(uring_override_creds, selinux_uring_override_creds), |
7195 | LSM_HOOK_INIT(uring_sqpoll, selinux_uring_sqpoll), |
7196 | LSM_HOOK_INIT(uring_cmd, selinux_uring_cmd), |
7197 | #endif |
7198 | |
7199 | /* |
7200 | * PUT "CLONING" (ACCESSING + ALLOCATING) HOOKS HERE |
7201 | */ |
7202 | LSM_HOOK_INIT(fs_context_submount, selinux_fs_context_submount), |
7203 | LSM_HOOK_INIT(fs_context_dup, selinux_fs_context_dup), |
7204 | LSM_HOOK_INIT(fs_context_parse_param, selinux_fs_context_parse_param), |
7205 | LSM_HOOK_INIT(sb_eat_lsm_opts, selinux_sb_eat_lsm_opts), |
7206 | #ifdef CONFIG_SECURITY_NETWORK_XFRM |
7207 | LSM_HOOK_INIT(xfrm_policy_clone_security, selinux_xfrm_policy_clone), |
7208 | #endif |
7209 | |
7210 | /* |
7211 | * PUT "ALLOCATING" HOOKS HERE |
7212 | */ |
7213 | LSM_HOOK_INIT(msg_msg_alloc_security, selinux_msg_msg_alloc_security), |
7214 | LSM_HOOK_INIT(msg_queue_alloc_security, |
7215 | selinux_msg_queue_alloc_security), |
7216 | LSM_HOOK_INIT(shm_alloc_security, selinux_shm_alloc_security), |
7217 | LSM_HOOK_INIT(sb_alloc_security, selinux_sb_alloc_security), |
7218 | LSM_HOOK_INIT(inode_alloc_security, selinux_inode_alloc_security), |
7219 | LSM_HOOK_INIT(sem_alloc_security, selinux_sem_alloc_security), |
7220 | LSM_HOOK_INIT(secid_to_secctx, selinux_secid_to_secctx), |
7221 | LSM_HOOK_INIT(inode_getsecctx, selinux_inode_getsecctx), |
7222 | LSM_HOOK_INIT(sk_alloc_security, selinux_sk_alloc_security), |
7223 | LSM_HOOK_INIT(tun_dev_alloc_security, selinux_tun_dev_alloc_security), |
7224 | #ifdef CONFIG_SECURITY_INFINIBAND |
7225 | LSM_HOOK_INIT(ib_alloc_security, selinux_ib_alloc_security), |
7226 | #endif |
7227 | #ifdef CONFIG_SECURITY_NETWORK_XFRM |
7228 | LSM_HOOK_INIT(xfrm_policy_alloc_security, selinux_xfrm_policy_alloc), |
7229 | LSM_HOOK_INIT(xfrm_state_alloc, selinux_xfrm_state_alloc), |
7230 | LSM_HOOK_INIT(xfrm_state_alloc_acquire, |
7231 | selinux_xfrm_state_alloc_acquire), |
7232 | #endif |
7233 | #ifdef CONFIG_KEYS |
7234 | LSM_HOOK_INIT(key_alloc, selinux_key_alloc), |
7235 | #endif |
7236 | #ifdef CONFIG_AUDIT |
7237 | LSM_HOOK_INIT(audit_rule_init, selinux_audit_rule_init), |
7238 | #endif |
7239 | #ifdef CONFIG_BPF_SYSCALL |
7240 | LSM_HOOK_INIT(bpf_map_alloc_security, selinux_bpf_map_alloc), |
7241 | LSM_HOOK_INIT(bpf_prog_alloc_security, selinux_bpf_prog_alloc), |
7242 | #endif |
7243 | #ifdef CONFIG_PERF_EVENTS |
7244 | LSM_HOOK_INIT(perf_event_alloc, selinux_perf_event_alloc), |
7245 | #endif |
7246 | }; |
7247 | |
7248 | static __init int selinux_init(void) |
7249 | { |
7250 | pr_info("SELinux: Initializing.\n" ); |
7251 | |
7252 | memset(&selinux_state, 0, sizeof(selinux_state)); |
7253 | enforcing_set(selinux_enforcing_boot); |
7254 | selinux_avc_init(); |
7255 | mutex_init(&selinux_state.status_lock); |
7256 | mutex_init(&selinux_state.policy_mutex); |
7257 | |
7258 | /* Set the security state for the initial task. */ |
7259 | cred_init_security(); |
7260 | |
7261 | default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC); |
7262 | if (!default_noexec) |
7263 | pr_notice("SELinux: virtual memory is executable by default\n" ); |
7264 | |
7265 | avc_init(); |
7266 | |
7267 | avtab_cache_init(); |
7268 | |
7269 | ebitmap_cache_init(); |
7270 | |
7271 | hashtab_cache_init(); |
7272 | |
7273 | security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks), "selinux" ); |
7274 | |
7275 | if (avc_add_callback(selinux_netcache_avc_callback, AVC_CALLBACK_RESET)) |
7276 | panic(fmt: "SELinux: Unable to register AVC netcache callback\n" ); |
7277 | |
7278 | if (avc_add_callback(selinux_lsm_notifier_avc_callback, AVC_CALLBACK_RESET)) |
7279 | panic(fmt: "SELinux: Unable to register AVC LSM notifier callback\n" ); |
7280 | |
7281 | if (selinux_enforcing_boot) |
7282 | pr_debug("SELinux: Starting in enforcing mode\n" ); |
7283 | else |
7284 | pr_debug("SELinux: Starting in permissive mode\n" ); |
7285 | |
7286 | fs_validate_description(name: "selinux" , desc: selinux_fs_parameters); |
7287 | |
7288 | return 0; |
7289 | } |
7290 | |
7291 | static void delayed_superblock_init(struct super_block *sb, void *unused) |
7292 | { |
7293 | selinux_set_mnt_opts(sb, NULL, kern_flags: 0, NULL); |
7294 | } |
7295 | |
7296 | void selinux_complete_init(void) |
7297 | { |
7298 | pr_debug("SELinux: Completing initialization.\n" ); |
7299 | |
7300 | /* Set up any superblocks initialized prior to the policy load. */ |
7301 | pr_debug("SELinux: Setting up existing superblocks.\n" ); |
7302 | iterate_supers(delayed_superblock_init, NULL); |
7303 | } |
7304 | |
7305 | /* SELinux requires early initialization in order to label |
7306 | all processes and objects when they are created. */ |
7307 | DEFINE_LSM(selinux) = { |
7308 | .name = "selinux" , |
7309 | .flags = LSM_FLAG_LEGACY_MAJOR | LSM_FLAG_EXCLUSIVE, |
7310 | .enabled = &selinux_enabled_boot, |
7311 | .blobs = &selinux_blob_sizes, |
7312 | .init = selinux_init, |
7313 | }; |
7314 | |
7315 | #if defined(CONFIG_NETFILTER) |
7316 | static const struct nf_hook_ops selinux_nf_ops[] = { |
7317 | { |
7318 | .hook = selinux_ip_postroute, |
7319 | .pf = NFPROTO_IPV4, |
7320 | .hooknum = NF_INET_POST_ROUTING, |
7321 | .priority = NF_IP_PRI_SELINUX_LAST, |
7322 | }, |
7323 | { |
7324 | .hook = selinux_ip_forward, |
7325 | .pf = NFPROTO_IPV4, |
7326 | .hooknum = NF_INET_FORWARD, |
7327 | .priority = NF_IP_PRI_SELINUX_FIRST, |
7328 | }, |
7329 | { |
7330 | .hook = selinux_ip_output, |
7331 | .pf = NFPROTO_IPV4, |
7332 | .hooknum = NF_INET_LOCAL_OUT, |
7333 | .priority = NF_IP_PRI_SELINUX_FIRST, |
7334 | }, |
7335 | #if IS_ENABLED(CONFIG_IPV6) |
7336 | { |
7337 | .hook = selinux_ip_postroute, |
7338 | .pf = NFPROTO_IPV6, |
7339 | .hooknum = NF_INET_POST_ROUTING, |
7340 | .priority = NF_IP6_PRI_SELINUX_LAST, |
7341 | }, |
7342 | { |
7343 | .hook = selinux_ip_forward, |
7344 | .pf = NFPROTO_IPV6, |
7345 | .hooknum = NF_INET_FORWARD, |
7346 | .priority = NF_IP6_PRI_SELINUX_FIRST, |
7347 | }, |
7348 | { |
7349 | .hook = selinux_ip_output, |
7350 | .pf = NFPROTO_IPV6, |
7351 | .hooknum = NF_INET_LOCAL_OUT, |
7352 | .priority = NF_IP6_PRI_SELINUX_FIRST, |
7353 | }, |
7354 | #endif /* IPV6 */ |
7355 | }; |
7356 | |
7357 | static int __net_init selinux_nf_register(struct net *net) |
7358 | { |
7359 | return nf_register_net_hooks(net, reg: selinux_nf_ops, |
7360 | ARRAY_SIZE(selinux_nf_ops)); |
7361 | } |
7362 | |
7363 | static void __net_exit selinux_nf_unregister(struct net *net) |
7364 | { |
7365 | nf_unregister_net_hooks(net, reg: selinux_nf_ops, |
7366 | ARRAY_SIZE(selinux_nf_ops)); |
7367 | } |
7368 | |
7369 | static struct pernet_operations selinux_net_ops = { |
7370 | .init = selinux_nf_register, |
7371 | .exit = selinux_nf_unregister, |
7372 | }; |
7373 | |
7374 | static int __init selinux_nf_ip_init(void) |
7375 | { |
7376 | int err; |
7377 | |
7378 | if (!selinux_enabled_boot) |
7379 | return 0; |
7380 | |
7381 | pr_debug("SELinux: Registering netfilter hooks\n" ); |
7382 | |
7383 | err = register_pernet_subsys(&selinux_net_ops); |
7384 | if (err) |
7385 | panic(fmt: "SELinux: register_pernet_subsys: error %d\n" , err); |
7386 | |
7387 | return 0; |
7388 | } |
7389 | __initcall(selinux_nf_ip_init); |
7390 | #endif /* CONFIG_NETFILTER */ |
7391 | |