1	// SPDX-License-Identifier: GPL-2.0-only
2	/* Updated: Karl MacMillan <kmacmillan@tresys.com>
3	*
4	* Added conditional policy language extensions
5	*
6	* Updated: Hewlett-Packard <paul@paul-moore.com>
7	*
8	* Added support for the policy capability bitmap
9	*
10	* Copyright (C) 2007 Hewlett-Packard Development Company, L.P.
11	* Copyright (C) 2003 - 2004 Tresys Technology, LLC
12	* Copyright (C) 2004 Red Hat, Inc., James Morris <jmorris@redhat.com>
13	*/
14
15	#include <linux/kernel.h>
16	#include <linux/pagemap.h>
17	#include <linux/slab.h>
18	#include <linux/vmalloc.h>
19	#include <linux/fs.h>
20	#include <linux/fs_context.h>
21	#include <linux/mount.h>
22	#include <linux/mutex.h>
23	#include <linux/namei.h>
24	#include <linux/init.h>
25	#include <linux/string.h>
26	#include <linux/security.h>
27	#include <linux/major.h>
28	#include <linux/seq_file.h>
29	#include <linux/percpu.h>
30	#include <linux/audit.h>
31	#include <linux/uaccess.h>
32	#include <linux/kobject.h>
33	#include <linux/ctype.h>
34
35	/* selinuxfs pseudo filesystem for exporting the security policy API.
36	Based on the proc code and the fs/nfsd/nfsctl.c code. */
37
38	#include "flask.h"
39	#include "avc.h"
40	#include "avc_ss.h"
41	#include "security.h"
42	#include "objsec.h"
43	#include "conditional.h"
44	#include "ima.h"
45
46	enum sel_inos {
47	SEL_ROOT_INO = 2,
48	SEL_LOAD, /* load policy */
49	SEL_ENFORCE, /* get or set enforcing status */
50	SEL_CONTEXT, /* validate context */
51	SEL_ACCESS, /* compute access decision */
52	SEL_CREATE, /* compute create labeling decision */
53	SEL_RELABEL, /* compute relabeling decision */
54	SEL_USER, /* compute reachable user contexts */
55	SEL_POLICYVERS, /* return policy version for this kernel */
56	SEL_COMMIT_BOOLS, /* commit new boolean values */
57	SEL_MLS, /* return if MLS policy is enabled */
58	SEL_DISABLE, /* disable SELinux until next reboot */
59	SEL_MEMBER, /* compute polyinstantiation membership decision */
60	SEL_CHECKREQPROT, /* check requested protection, not kernel-applied one */
61	SEL_COMPAT_NET, /* whether to use old compat network packet controls */
62	SEL_REJECT_UNKNOWN, /* export unknown reject handling to userspace */
63	SEL_DENY_UNKNOWN, /* export unknown deny handling to userspace */
64	SEL_STATUS, /* export current status using mmap() */
65	SEL_POLICY, /* allow userspace to read the in kernel policy */
66	SEL_VALIDATE_TRANS, /* compute validatetrans decision */
67	SEL_INO_NEXT, /* The next inode number to use */
68	};
69
70	struct selinux_fs_info {
71	struct dentry *bool_dir;
72	unsigned int bool_num;
73	char **bool_pending_names;
74	int *bool_pending_values;
75	struct dentry *class_dir;
76	unsigned long last_class_ino;
77	bool policy_opened;
78	struct dentry *policycap_dir;
79	unsigned long last_ino;
80	struct super_block *sb;
81	};
82
83	static int selinux_fs_info_create(struct super_block *sb)
84	{
85	struct selinux_fs_info *fsi;
86
87	fsi = kzalloc(size: sizeof(*fsi), GFP_KERNEL);
88	if (!fsi)
89	return -ENOMEM;
90
91	fsi->last_ino = SEL_INO_NEXT - 1;
92	fsi->sb = sb;
93	sb->s_fs_info = fsi;
94	return 0;
95	}
96
97	static void selinux_fs_info_free(struct super_block *sb)
98	{
99	struct selinux_fs_info *fsi = sb->s_fs_info;
100	unsigned int i;
101
102	if (fsi) {
103	for (i = 0; i < fsi->bool_num; i++)
104	kfree(objp: fsi->bool_pending_names[i]);
105	kfree(objp: fsi->bool_pending_names);
106	kfree(objp: fsi->bool_pending_values);
107	}
108	kfree(objp: sb->s_fs_info);
109	sb->s_fs_info = NULL;
110	}
111
112	#define SEL_INITCON_INO_OFFSET 0x01000000
113	#define SEL_BOOL_INO_OFFSET 0x02000000
114	#define SEL_CLASS_INO_OFFSET 0x04000000
115	#define SEL_POLICYCAP_INO_OFFSET 0x08000000
116	#define SEL_INO_MASK 0x00ffffff
117
118	#define BOOL_DIR_NAME "booleans"
119	#define CLASS_DIR_NAME "class"
120	#define POLICYCAP_DIR_NAME "policy_capabilities"
121
122	#define TMPBUFLEN 12
123	static ssize_t sel_read_enforce(struct file *filp, char __user *buf,
124	size_t count, loff_t *ppos)
125	{
126	char tmpbuf[TMPBUFLEN];
127	ssize_t length;
128
129	length = scnprintf(buf: tmpbuf, TMPBUFLEN, fmt: "%d",
130	enforcing_enabled());
131	return simple_read_from_buffer(to: buf, count, ppos, from: tmpbuf, available: length);
132	}
133
134	#ifdef CONFIG_SECURITY_SELINUX_DEVELOP
135	static ssize_t sel_write_enforce(struct file *file, const char __user *buf,
136	size_t count, loff_t *ppos)
137
138	{
139	char *page = NULL;
140	ssize_t length;
141	int scan_value;
142	bool old_value, new_value;
143
144	if (count >= PAGE_SIZE)
145	return -ENOMEM;
146
147	/* No partial writes. */
148	if (*ppos != 0)
149	return -EINVAL;
150
151	page = memdup_user_nul(buf, count);
152	if (IS_ERR(ptr: page))
153	return PTR_ERR(ptr: page);
154
155	length = -EINVAL;
156	if (sscanf(page, "%d", &scan_value) != 1)
157	goto out;
158
159	new_value = !!scan_value;
160
161	old_value = enforcing_enabled();
162	if (new_value != old_value) {
163	length = avc_has_perm(current_sid(), SECINITSID_SECURITY,
164	SECCLASS_SECURITY, SECURITY__SETENFORCE,
165	NULL);
166	if (length)
167	goto out;
168	audit_log(ctx: audit_context(), GFP_KERNEL, AUDIT_MAC_STATUS,
169	fmt: "enforcing=%d old_enforcing=%d auid=%u ses=%u"
170	" enabled=1 old-enabled=1 lsm=selinux res=1",
171	new_value, old_value,
172	from_kuid(to: &init_user_ns, uid: audit_get_loginuid(current)),
173	audit_get_sessionid(current));
174	enforcing_set(new_value);
175	if (new_value)
176	avc_ss_reset(0);
177	selnl_notify_setenforce(new_value);
178	selinux_status_update_setenforce(new_value);
179	if (!new_value)
180	call_blocking_lsm_notifier(event: LSM_POLICY_CHANGE, NULL);
181
182	selinux_ima_measure_state();
183	}
184	length = count;
185	out:
186	kfree(objp: page);
187	return length;
188	}
189	#else
190	#define sel_write_enforce NULL
191	#endif
192
193	static const struct file_operations sel_enforce_ops = {
194	.read = sel_read_enforce,
195	.write = sel_write_enforce,
196	.llseek = generic_file_llseek,
197	};
198
199	static ssize_t sel_read_handle_unknown(struct file *filp, char __user *buf,
200	size_t count, loff_t *ppos)
201	{
202	char tmpbuf[TMPBUFLEN];
203	ssize_t length;
204	ino_t ino = file_inode(f: filp)->i_ino;
205	int handle_unknown = (ino == SEL_REJECT_UNKNOWN) ?
206	security_get_reject_unknown() :
207	!security_get_allow_unknown();
208
209	length = scnprintf(buf: tmpbuf, TMPBUFLEN, fmt: "%d", handle_unknown);
210	return simple_read_from_buffer(to: buf, count, ppos, from: tmpbuf, available: length);
211	}
212
213	static const struct file_operations sel_handle_unknown_ops = {
214	.read = sel_read_handle_unknown,
215	.llseek = generic_file_llseek,
216	};
217
218	static int sel_open_handle_status(struct inode *inode, struct file *filp)
219	{
220	struct page *status = selinux_kernel_status_page();
221
222	if (!status)
223	return -ENOMEM;
224
225	filp->private_data = status;
226
227	return 0;
228	}
229
230	static ssize_t sel_read_handle_status(struct file *filp, char __user *buf,
231	size_t count, loff_t *ppos)
232	{
233	struct page *status = filp->private_data;
234
235	BUG_ON(!status);
236
237	return simple_read_from_buffer(buf, count, ppos,
238	page_address(status),
239	sizeof(struct selinux_kernel_status));
240	}
241
242	static int sel_mmap_handle_status(struct file *filp,
243	struct vm_area_struct *vma)
244	{
245	struct page *status = filp->private_data;
246	unsigned long size = vma->vm_end - vma->vm_start;
247
248	BUG_ON(!status);
249
250	/* only allows one page from the head */
251	if (vma->vm_pgoff > 0 || size != PAGE_SIZE)
252	return -EIO;
253	/* disallow writable mapping */
254	if (vma->vm_flags & VM_WRITE)
255	return -EPERM;
256	/* disallow mprotect() turns it into writable */
257	vm_flags_clear(vma, VM_MAYWRITE);
258
259	return remap_pfn_range(vma, addr: vma->vm_start,
260	page_to_pfn(status),
261	size, vma->vm_page_prot);
262	}
263
264	static const struct file_operations sel_handle_status_ops = {
265	.open = sel_open_handle_status,
266	.read = sel_read_handle_status,
267	.mmap = sel_mmap_handle_status,
268	.llseek = generic_file_llseek,
269	};
270
271	static ssize_t sel_write_disable(struct file *file, const char __user *buf,
272	size_t count, loff_t *ppos)
273
274	{
275	char *page;
276	ssize_t length;
277	int new_value;
278
279	if (count >= PAGE_SIZE)
280	return -ENOMEM;
281
282	/* No partial writes. */
283	if (*ppos != 0)
284	return -EINVAL;
285
286	page = memdup_user_nul(buf, count);
287	if (IS_ERR(ptr: page))
288	return PTR_ERR(ptr: page);
289
290	if (sscanf(page, "%d", &new_value) != 1) {
291	length = -EINVAL;
292	goto out;
293	}
294	length = count;
295
296	if (new_value) {
297	pr_err("SELinux: https://github.com/SELinuxProject/selinux-kernel/wiki/DEPRECATE-runtime-disable\n");
298	pr_err("SELinux: Runtime disable is not supported, use selinux=0 on the kernel cmdline.\n");
299	}
300
301	out:
302	kfree(objp: page);
303	return length;
304	}
305
306	static const struct file_operations sel_disable_ops = {
307	.write = sel_write_disable,
308	.llseek = generic_file_llseek,
309	};
310
311	static ssize_t sel_read_policyvers(struct file *filp, char __user *buf,
312	size_t count, loff_t *ppos)
313	{
314	char tmpbuf[TMPBUFLEN];
315	ssize_t length;
316
317	length = scnprintf(buf: tmpbuf, TMPBUFLEN, fmt: "%u", POLICYDB_VERSION_MAX);
318	return simple_read_from_buffer(to: buf, count, ppos, from: tmpbuf, available: length);
319	}
320
321	static const struct file_operations sel_policyvers_ops = {
322	.read = sel_read_policyvers,
323	.llseek = generic_file_llseek,
324	};
325
326	/* declaration for sel_write_load */
327	static int sel_make_bools(struct selinux_policy *newpolicy, struct dentry *bool_dir,
328	unsigned int *bool_num, char ***bool_pending_names,
329	int **bool_pending_values);
330	static int sel_make_classes(struct selinux_policy *newpolicy,
331	struct dentry *class_dir,
332	unsigned long *last_class_ino);
333
334	/* declaration for sel_make_class_dirs */
335	static struct dentry *sel_make_dir(struct dentry *dir, const char *name,
336	unsigned long *ino);
337
338	/* declaration for sel_make_policy_nodes */
339	static struct dentry *sel_make_swapover_dir(struct super_block *sb,
340	unsigned long *ino);
341
342	static ssize_t sel_read_mls(struct file *filp, char __user *buf,
343	size_t count, loff_t *ppos)
344	{
345	char tmpbuf[TMPBUFLEN];
346	ssize_t length;
347
348	length = scnprintf(buf: tmpbuf, TMPBUFLEN, fmt: "%d",
349	security_mls_enabled());
350	return simple_read_from_buffer(to: buf, count, ppos, from: tmpbuf, available: length);
351	}
352
353	static const struct file_operations sel_mls_ops = {
354	.read = sel_read_mls,
355	.llseek = generic_file_llseek,
356	};
357
358	struct policy_load_memory {
359	size_t len;
360	void *data;
361	};
362
363	static int sel_open_policy(struct inode *inode, struct file *filp)
364	{
365	struct selinux_fs_info *fsi = inode->i_sb->s_fs_info;
366	struct policy_load_memory *plm = NULL;
367	int rc;
368
369	BUG_ON(filp->private_data);
370
371	mutex_lock(&selinux_state.policy_mutex);
372
373	rc = avc_has_perm(current_sid(), SECINITSID_SECURITY,
374	SECCLASS_SECURITY, SECURITY__READ_POLICY, NULL);
375	if (rc)
376	goto err;
377
378	rc = -EBUSY;
379	if (fsi->policy_opened)
380	goto err;
381
382	rc = -ENOMEM;
383	plm = kzalloc(size: sizeof(*plm), GFP_KERNEL);
384	if (!plm)
385	goto err;
386
387	rc = security_read_policy(&plm->data, &plm->len);
388	if (rc)
389	goto err;
390
391	if ((size_t)i_size_read(inode) != plm->len) {
392	inode_lock(inode);
393	i_size_write(inode, i_size: plm->len);
394	inode_unlock(inode);
395	}
396
397	fsi->policy_opened = 1;
398
399	filp->private_data = plm;
400
401	mutex_unlock(lock: &selinux_state.policy_mutex);
402
403	return 0;
404	err:
405	mutex_unlock(lock: &selinux_state.policy_mutex);
406
407	if (plm)
408	vfree(addr: plm->data);
409	kfree(objp: plm);
410	return rc;
411	}
412
413	static int sel_release_policy(struct inode *inode, struct file *filp)
414	{
415	struct selinux_fs_info *fsi = inode->i_sb->s_fs_info;
416	struct policy_load_memory *plm = filp->private_data;
417
418	BUG_ON(!plm);
419
420	fsi->policy_opened = 0;
421
422	vfree(addr: plm->data);
423	kfree(objp: plm);
424
425	return 0;
426	}
427
428	static ssize_t sel_read_policy(struct file *filp, char __user *buf,
429	size_t count, loff_t *ppos)
430	{
431	struct policy_load_memory *plm = filp->private_data;
432	int ret;
433
434	ret = avc_has_perm(current_sid(), SECINITSID_SECURITY,
435	SECCLASS_SECURITY, SECURITY__READ_POLICY, NULL);
436	if (ret)
437	return ret;
438
439	return simple_read_from_buffer(to: buf, count, ppos, from: plm->data, available: plm->len);
440	}
441
442	static vm_fault_t sel_mmap_policy_fault(struct vm_fault *vmf)
443	{
444	struct policy_load_memory *plm = vmf->vma->vm_file->private_data;
445	unsigned long offset;
446	struct page *page;
447
448	if (vmf->flags & (FAULT_FLAG_MKWRITE | FAULT_FLAG_WRITE))
449	return VM_FAULT_SIGBUS;
450
451	offset = vmf->pgoff << PAGE_SHIFT;
452	if (offset >= roundup(plm->len, PAGE_SIZE))
453	return VM_FAULT_SIGBUS;
454
455	page = vmalloc_to_page(addr: plm->data + offset);
456	get_page(page);
457
458	vmf->page = page;
459
460	return 0;
461	}
462
463	static const struct vm_operations_struct sel_mmap_policy_ops = {
464	.fault = sel_mmap_policy_fault,
465	.page_mkwrite = sel_mmap_policy_fault,
466	};
467
468	static int sel_mmap_policy(struct file *filp, struct vm_area_struct *vma)
469	{
470	if (vma->vm_flags & VM_SHARED) {
471	/* do not allow mprotect to make mapping writable */
472	vm_flags_clear(vma, VM_MAYWRITE);
473
474	if (vma->vm_flags & VM_WRITE)
475	return -EACCES;
476	}
477
478	vm_flags_set(vma, VM_DONTEXPAND | VM_DONTDUMP);
479	vma->vm_ops = &sel_mmap_policy_ops;
480
481	return 0;
482	}
483
484	static const struct file_operations sel_policy_ops = {
485	.open = sel_open_policy,
486	.read = sel_read_policy,
487	.mmap = sel_mmap_policy,
488	.release = sel_release_policy,
489	.llseek = generic_file_llseek,
490	};
491
492	static void sel_remove_old_bool_data(unsigned int bool_num, char **bool_names,
493	int *bool_values)
494	{
495	u32 i;
496
497	/* bool_dir cleanup */
498	for (i = 0; i < bool_num; i++)
499	kfree(objp: bool_names[i]);
500	kfree(objp: bool_names);
501	kfree(objp: bool_values);
502	}
503
504	static int sel_make_policy_nodes(struct selinux_fs_info *fsi,
505	struct selinux_policy *newpolicy)
506	{
507	int ret = 0;
508	struct dentry *tmp_parent, *tmp_bool_dir, *tmp_class_dir;
509	unsigned int bool_num = 0;
510	char **bool_names = NULL;
511	int *bool_values = NULL;
512	unsigned long tmp_ino = fsi->last_ino; /* Don't increment last_ino in this function */
513
514	tmp_parent = sel_make_swapover_dir(sb: fsi->sb, ino: &tmp_ino);
515	if (IS_ERR(ptr: tmp_parent))
516	return PTR_ERR(ptr: tmp_parent);
517
518	tmp_ino = fsi->bool_dir->d_inode->i_ino - 1; /* sel_make_dir will increment and set */
519	tmp_bool_dir = sel_make_dir(dir: tmp_parent, BOOL_DIR_NAME, ino: &tmp_ino);
520	if (IS_ERR(ptr: tmp_bool_dir)) {
521	ret = PTR_ERR(ptr: tmp_bool_dir);
522	goto out;
523	}
524
525	tmp_ino = fsi->class_dir->d_inode->i_ino - 1; /* sel_make_dir will increment and set */
526	tmp_class_dir = sel_make_dir(dir: tmp_parent, CLASS_DIR_NAME, ino: &tmp_ino);
527	if (IS_ERR(ptr: tmp_class_dir)) {
528	ret = PTR_ERR(ptr: tmp_class_dir);
529	goto out;
530	}
531
532	ret = sel_make_bools(newpolicy, bool_dir: tmp_bool_dir, bool_num: &bool_num,
533	bool_pending_names: &bool_names, bool_pending_values: &bool_values);
534	if (ret)
535	goto out;
536
537	ret = sel_make_classes(newpolicy, class_dir: tmp_class_dir,
538	last_class_ino: &fsi->last_class_ino);
539	if (ret)
540	goto out;
541
542	lock_rename(tmp_parent, fsi->sb->s_root);
543
544	/* booleans */
545	d_exchange(tmp_bool_dir, fsi->bool_dir);
546
547	swap(fsi->bool_num, bool_num);
548	swap(fsi->bool_pending_names, bool_names);
549	swap(fsi->bool_pending_values, bool_values);
550
551	fsi->bool_dir = tmp_bool_dir;
552
553	/* classes */
554	d_exchange(tmp_class_dir, fsi->class_dir);
555	fsi->class_dir = tmp_class_dir;
556
557	unlock_rename(tmp_parent, fsi->sb->s_root);
558
559	out:
560	sel_remove_old_bool_data(bool_num, bool_names, bool_values);
561	/* Since the other temporary dirs are children of tmp_parent
562	* this will handle all the cleanup in the case of a failure before
563	* the swapover
564	*/
565	simple_recursive_removal(tmp_parent, NULL);
566
567	return ret;
568	}
569
570	static ssize_t sel_write_load(struct file *file, const char __user *buf,
571	size_t count, loff_t *ppos)
572
573	{
574	struct selinux_fs_info *fsi = file_inode(f: file)->i_sb->s_fs_info;
575	struct selinux_load_state load_state;
576	ssize_t length;
577	void *data = NULL;
578
579	mutex_lock(&selinux_state.policy_mutex);
580
581	length = avc_has_perm(current_sid(), SECINITSID_SECURITY,
582	SECCLASS_SECURITY, SECURITY__LOAD_POLICY, NULL);
583	if (length)
584	goto out;
585
586	/* No partial writes. */
587	length = -EINVAL;
588	if (*ppos != 0)
589	goto out;
590
591	length = -ENOMEM;
592	data = vmalloc(size: count);
593	if (!data)
594	goto out;
595
596	length = -EFAULT;
597	if (copy_from_user(to: data, from: buf, n: count) != 0)
598	goto out;
599
600	length = security_load_policy(data, count, &load_state);
601	if (length) {
602	pr_warn_ratelimited("SELinux: failed to load policy\n");
603	goto out;
604	}
605
606	length = sel_make_policy_nodes(fsi, newpolicy: load_state.policy);
607	if (length) {
608	pr_warn_ratelimited("SELinux: failed to initialize selinuxfs\n");
609	selinux_policy_cancel(&load_state);
610	goto out;
611	}
612
613	selinux_policy_commit(&load_state);
614
615	length = count;
616
617	audit_log(ctx: audit_context(), GFP_KERNEL, AUDIT_MAC_POLICY_LOAD,
618	fmt: "auid=%u ses=%u lsm=selinux res=1",
619	from_kuid(to: &init_user_ns, uid: audit_get_loginuid(current)),
620	audit_get_sessionid(current));
621	out:
622	mutex_unlock(lock: &selinux_state.policy_mutex);
623	vfree(addr: data);
624	return length;
625	}
626
627	static const struct file_operations sel_load_ops = {
628	.write = sel_write_load,
629	.llseek = generic_file_llseek,
630	};
631
632	static ssize_t sel_write_context(struct file *file, char *buf, size_t size)
633	{
634	char *canon = NULL;
635	u32 sid, len;
636	ssize_t length;
637
638	length = avc_has_perm(current_sid(), SECINITSID_SECURITY,
639	SECCLASS_SECURITY, SECURITY__CHECK_CONTEXT, NULL);
640	if (length)
641	goto out;
642
643	length = security_context_to_sid(buf, size, &sid, GFP_KERNEL);
644	if (length)
645	goto out;
646
647	length = security_sid_to_context(sid, &canon, &len);
648	if (length)
649	goto out;
650
651	length = -ERANGE;
652	if (len > SIMPLE_TRANSACTION_LIMIT) {
653	pr_err("SELinux: %s: context size (%u) exceeds "
654	"payload max\n", __func__, len);
655	goto out;
656	}
657
658	memcpy(buf, canon, len);
659	length = len;
660	out:
661	kfree(objp: canon);
662	return length;
663	}
664
665	static ssize_t sel_read_checkreqprot(struct file *filp, char __user *buf,
666	size_t count, loff_t *ppos)
667	{
668	char tmpbuf[TMPBUFLEN];
669	ssize_t length;
670
671	length = scnprintf(buf: tmpbuf, TMPBUFLEN, fmt: "%u",
672	checkreqprot_get());
673	return simple_read_from_buffer(to: buf, count, ppos, from: tmpbuf, available: length);
674	}
675
676	static ssize_t sel_write_checkreqprot(struct file *file, const char __user *buf,
677	size_t count, loff_t *ppos)
678	{
679	char *page;
680	ssize_t length;
681	unsigned int new_value;
682
683	length = avc_has_perm(current_sid(), SECINITSID_SECURITY,
684	SECCLASS_SECURITY, SECURITY__SETCHECKREQPROT,
685	NULL);
686	if (length)
687	return length;
688
689	if (count >= PAGE_SIZE)
690	return -ENOMEM;
691
692	/* No partial writes. */
693	if (*ppos != 0)
694	return -EINVAL;
695
696	page = memdup_user_nul(buf, count);
697	if (IS_ERR(ptr: page))
698	return PTR_ERR(ptr: page);
699
700	if (sscanf(page, "%u", &new_value) != 1) {
701	length = -EINVAL;
702	goto out;
703	}
704	length = count;
705
706	if (new_value) {
707	char comm[sizeof(current->comm)];
708
709	memcpy(comm, current->comm, sizeof(comm));
710	pr_err("SELinux: %s (%d) set checkreqprot to 1. This is no longer supported.\n",
711	comm, current->pid);
712	}
713
714	selinux_ima_measure_state();
715
716	out:
717	kfree(objp: page);
718	return length;
719	}
720	static const struct file_operations sel_checkreqprot_ops = {
721	.read = sel_read_checkreqprot,
722	.write = sel_write_checkreqprot,
723	.llseek = generic_file_llseek,
724	};
725
726	static ssize_t sel_write_validatetrans(struct file *file,
727	const char __user *buf,
728	size_t count, loff_t *ppos)
729	{
730	char *oldcon = NULL, *newcon = NULL, *taskcon = NULL;
731	char *req = NULL;
732	u32 osid, nsid, tsid;
733	u16 tclass;
734	int rc;
735
736	rc = avc_has_perm(current_sid(), SECINITSID_SECURITY,
737	SECCLASS_SECURITY, SECURITY__VALIDATE_TRANS, NULL);
738	if (rc)
739	goto out;
740
741	rc = -ENOMEM;
742	if (count >= PAGE_SIZE)
743	goto out;
744
745	/* No partial writes. */
746	rc = -EINVAL;
747	if (*ppos != 0)
748	goto out;
749
750	req = memdup_user_nul(buf, count);
751	if (IS_ERR(ptr: req)) {
752	rc = PTR_ERR(ptr: req);
753	req = NULL;
754	goto out;
755	}
756
757	rc = -ENOMEM;
758	oldcon = kzalloc(size: count + 1, GFP_KERNEL);
759	if (!oldcon)
760	goto out;
761
762	newcon = kzalloc(size: count + 1, GFP_KERNEL);
763	if (!newcon)
764	goto out;
765
766	taskcon = kzalloc(size: count + 1, GFP_KERNEL);
767	if (!taskcon)
768	goto out;
769
770	rc = -EINVAL;
771	if (sscanf(req, "%s %s %hu %s", oldcon, newcon, &tclass, taskcon) != 4)
772	goto out;
773
774	rc = security_context_str_to_sid(oldcon, &osid, GFP_KERNEL);
775	if (rc)
776	goto out;
777
778	rc = security_context_str_to_sid(newcon, &nsid, GFP_KERNEL);
779	if (rc)
780	goto out;
781
782	rc = security_context_str_to_sid(taskcon, &tsid, GFP_KERNEL);
783	if (rc)
784	goto out;
785
786	rc = security_validate_transition_user(osid, nsid, tsid, tclass);
787	if (!rc)
788	rc = count;
789	out:
790	kfree(objp: req);
791	kfree(objp: oldcon);
792	kfree(objp: newcon);
793	kfree(objp: taskcon);
794	return rc;
795	}
796
797	static const struct file_operations sel_transition_ops = {
798	.write = sel_write_validatetrans,
799	.llseek = generic_file_llseek,
800	};
801
802	/*
803	* Remaining nodes use transaction based IO methods like nfsd/nfsctl.c
804	*/
805	static ssize_t sel_write_access(struct file *file, char *buf, size_t size);
806	static ssize_t sel_write_create(struct file *file, char *buf, size_t size);
807	static ssize_t sel_write_relabel(struct file *file, char *buf, size_t size);
808	static ssize_t sel_write_user(struct file *file, char *buf, size_t size);
809	static ssize_t sel_write_member(struct file *file, char *buf, size_t size);
810
811	static ssize_t (*const write_op[])(struct file *, char *, size_t) = {
812	[SEL_ACCESS] = sel_write_access,
813	[SEL_CREATE] = sel_write_create,
814	[SEL_RELABEL] = sel_write_relabel,
815	[SEL_USER] = sel_write_user,
816	[SEL_MEMBER] = sel_write_member,
817	[SEL_CONTEXT] = sel_write_context,
818	};
819
820	static ssize_t selinux_transaction_write(struct file *file, const char __user *buf, size_t size, loff_t *pos)
821	{
822	ino_t ino = file_inode(f: file)->i_ino;
823	char *data;
824	ssize_t rv;
825
826	if (ino >= ARRAY_SIZE(write_op) || !write_op[ino])
827	return -EINVAL;
828
829	data = simple_transaction_get(file, buf, size);
830	if (IS_ERR(ptr: data))
831	return PTR_ERR(ptr: data);
832
833	rv = write_op[ino](file, data, size);
834	if (rv > 0) {
835	simple_transaction_set(file, n: rv);
836	rv = size;
837	}
838	return rv;
839	}
840
841	static const struct file_operations transaction_ops = {
842	.write = selinux_transaction_write,
843	.read = simple_transaction_read,
844	.release = simple_transaction_release,
845	.llseek = generic_file_llseek,
846	};
847
848	/*
849	* payload - write methods
850	* If the method has a response, the response should be put in buf,
851	* and the length returned. Otherwise return 0 or and -error.
852	*/
853
854	static ssize_t sel_write_access(struct file *file, char *buf, size_t size)
855	{
856	char *scon = NULL, *tcon = NULL;
857	u32 ssid, tsid;
858	u16 tclass;
859	struct av_decision avd;
860	ssize_t length;
861
862	length = avc_has_perm(current_sid(), SECINITSID_SECURITY,
863	SECCLASS_SECURITY, SECURITY__COMPUTE_AV, NULL);
864	if (length)
865	goto out;
866
867	length = -ENOMEM;
868	scon = kzalloc(size: size + 1, GFP_KERNEL);
869	if (!scon)
870	goto out;
871
872	length = -ENOMEM;
873	tcon = kzalloc(size: size + 1, GFP_KERNEL);
874	if (!tcon)
875	goto out;
876
877	length = -EINVAL;
878	if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
879	goto out;
880
881	length = security_context_str_to_sid(scon, &ssid, GFP_KERNEL);
882	if (length)
883	goto out;
884
885	length = security_context_str_to_sid(tcon, &tsid, GFP_KERNEL);
886	if (length)
887	goto out;
888
889	security_compute_av_user(ssid, tsid, tclass, &avd);
890
891	length = scnprintf(buf, SIMPLE_TRANSACTION_LIMIT,
892	fmt: "%x %x %x %x %u %x",
893	avd.allowed, 0xffffffff,
894	avd.auditallow, avd.auditdeny,
895	avd.seqno, avd.flags);
896	out:
897	kfree(objp: tcon);
898	kfree(objp: scon);
899	return length;
900	}
901
902	static ssize_t sel_write_create(struct file *file, char *buf, size_t size)
903	{
904	char *scon = NULL, *tcon = NULL;
905	char *namebuf = NULL, *objname = NULL;
906	u32 ssid, tsid, newsid;
907	u16 tclass;
908	ssize_t length;
909	char *newcon = NULL;
910	u32 len;
911	int nargs;
912
913	length = avc_has_perm(current_sid(), SECINITSID_SECURITY,
914	SECCLASS_SECURITY, SECURITY__COMPUTE_CREATE,
915	NULL);
916	if (length)
917	goto out;
918
919	length = -ENOMEM;
920	scon = kzalloc(size: size + 1, GFP_KERNEL);
921	if (!scon)
922	goto out;
923
924	length = -ENOMEM;
925	tcon = kzalloc(size: size + 1, GFP_KERNEL);
926	if (!tcon)
927	goto out;
928
929	length = -ENOMEM;
930	namebuf = kzalloc(size: size + 1, GFP_KERNEL);
931	if (!namebuf)
932	goto out;
933
934	length = -EINVAL;
935	nargs = sscanf(buf, "%s %s %hu %s", scon, tcon, &tclass, namebuf);
936	if (nargs < 3 || nargs > 4)
937	goto out;
938	if (nargs == 4) {
939	/*
940	* If and when the name of new object to be queried contains
941	* either whitespace or multibyte characters, they shall be
942	* encoded based on the percentage-encoding rule.
943	* If not encoded, the sscanf logic picks up only left-half
944	* of the supplied name; split by a whitespace unexpectedly.
945	*/
946	char *r, *w;
947	int c1, c2;
948
949	r = w = namebuf;
950	do {
951	c1 = *r++;
952	if (c1 == '+')
953	c1 = ' ';
954	else if (c1 == '%') {
955	c1 = hex_to_bin(ch: *r++);
956	if (c1 < 0)
957	goto out;
958	c2 = hex_to_bin(ch: *r++);
959	if (c2 < 0)
960	goto out;
961	c1 = (c1 << 4) | c2;
962	}
963	*w++ = c1;
964	} while (c1 != '\0');
965
966	objname = namebuf;
967	}
968
969	length = security_context_str_to_sid(scon, &ssid, GFP_KERNEL);
970	if (length)
971	goto out;
972
973	length = security_context_str_to_sid(tcon, &tsid, GFP_KERNEL);
974	if (length)
975	goto out;
976
977	length = security_transition_sid_user(ssid, tsid, tclass,
978	objname, &newsid);
979	if (length)
980	goto out;
981
982	length = security_sid_to_context(newsid, &newcon, &len);
983	if (length)
984	goto out;
985
986	length = -ERANGE;
987	if (len > SIMPLE_TRANSACTION_LIMIT) {
988	pr_err("SELinux: %s: context size (%u) exceeds "
989	"payload max\n", __func__, len);
990	goto out;
991	}
992
993	memcpy(buf, newcon, len);
994	length = len;
995	out:
996	kfree(objp: newcon);
997	kfree(objp: namebuf);
998	kfree(objp: tcon);
999	kfree(objp: scon);
1000	return length;
1001	}
1002
1003	static ssize_t sel_write_relabel(struct file *file, char *buf, size_t size)
1004	{
1005	char *scon = NULL, *tcon = NULL;
1006	u32 ssid, tsid, newsid;
1007	u16 tclass;
1008	ssize_t length;
1009	char *newcon = NULL;
1010	u32 len;
1011
1012	length = avc_has_perm(current_sid(), SECINITSID_SECURITY,
1013	SECCLASS_SECURITY, SECURITY__COMPUTE_RELABEL,
1014	NULL);
1015	if (length)
1016	goto out;
1017
1018	length = -ENOMEM;
1019	scon = kzalloc(size: size + 1, GFP_KERNEL);
1020	if (!scon)
1021	goto out;
1022
1023	length = -ENOMEM;
1024	tcon = kzalloc(size: size + 1, GFP_KERNEL);
1025	if (!tcon)
1026	goto out;
1027
1028	length = -EINVAL;
1029	if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
1030	goto out;
1031
1032	length = security_context_str_to_sid(scon, &ssid, GFP_KERNEL);
1033	if (length)
1034	goto out;
1035
1036	length = security_context_str_to_sid(tcon, &tsid, GFP_KERNEL);
1037	if (length)
1038	goto out;
1039
1040	length = security_change_sid(ssid, tsid, tclass, &newsid);
1041	if (length)
1042	goto out;
1043
1044	length = security_sid_to_context(newsid, &newcon, &len);
1045	if (length)
1046	goto out;
1047
1048	length = -ERANGE;
1049	if (len > SIMPLE_TRANSACTION_LIMIT)
1050	goto out;
1051
1052	memcpy(buf, newcon, len);
1053	length = len;
1054	out:
1055	kfree(objp: newcon);
1056	kfree(objp: tcon);
1057	kfree(objp: scon);
1058	return length;
1059	}
1060
1061	static ssize_t sel_write_user(struct file *file, char *buf, size_t size)
1062	{
1063	char *con = NULL, *user = NULL, *ptr;
1064	u32 sid, *sids = NULL;
1065	ssize_t length;
1066	char *newcon;
1067	int rc;
1068	u32 i, len, nsids;
1069
1070	length = avc_has_perm(current_sid(), SECINITSID_SECURITY,
1071	SECCLASS_SECURITY, SECURITY__COMPUTE_USER,
1072	NULL);
1073	if (length)
1074	goto out;
1075
1076	length = -ENOMEM;
1077	con = kzalloc(size: size + 1, GFP_KERNEL);
1078	if (!con)
1079	goto out;
1080
1081	length = -ENOMEM;
1082	user = kzalloc(size: size + 1, GFP_KERNEL);
1083	if (!user)
1084	goto out;
1085
1086	length = -EINVAL;
1087	if (sscanf(buf, "%s %s", con, user) != 2)
1088	goto out;
1089
1090	length = security_context_str_to_sid(con, &sid, GFP_KERNEL);
1091	if (length)
1092	goto out;
1093
1094	length = security_get_user_sids(sid, user, &sids, &nsids);
1095	if (length)
1096	goto out;
1097
1098	length = sprintf(buf, fmt: "%u", nsids) + 1;
1099	ptr = buf + length;
1100	for (i = 0; i < nsids; i++) {
1101	rc = security_sid_to_context(sids[i], &newcon, &len);
1102	if (rc) {
1103	length = rc;
1104	goto out;
1105	}
1106	if ((length + len) >= SIMPLE_TRANSACTION_LIMIT) {
1107	kfree(objp: newcon);
1108	length = -ERANGE;
1109	goto out;
1110	}
1111	memcpy(ptr, newcon, len);
1112	kfree(objp: newcon);
1113	ptr += len;
1114	length += len;
1115	}
1116	out:
1117	kfree(objp: sids);
1118	kfree(objp: user);
1119	kfree(objp: con);
1120	return length;
1121	}
1122
1123	static ssize_t sel_write_member(struct file *file, char *buf, size_t size)
1124	{
1125	char *scon = NULL, *tcon = NULL;
1126	u32 ssid, tsid, newsid;
1127	u16 tclass;
1128	ssize_t length;
1129	char *newcon = NULL;
1130	u32 len;
1131
1132	length = avc_has_perm(current_sid(), SECINITSID_SECURITY,
1133	SECCLASS_SECURITY, SECURITY__COMPUTE_MEMBER,
1134	NULL);
1135	if (length)
1136	goto out;
1137
1138	length = -ENOMEM;
1139	scon = kzalloc(size: size + 1, GFP_KERNEL);
1140	if (!scon)
1141	goto out;
1142
1143	length = -ENOMEM;
1144	tcon = kzalloc(size: size + 1, GFP_KERNEL);
1145	if (!tcon)
1146	goto out;
1147
1148	length = -EINVAL;
1149	if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
1150	goto out;
1151
1152	length = security_context_str_to_sid(scon, &ssid, GFP_KERNEL);
1153	if (length)
1154	goto out;
1155
1156	length = security_context_str_to_sid(tcon, &tsid, GFP_KERNEL);
1157	if (length)
1158	goto out;
1159
1160	length = security_member_sid(ssid, tsid, tclass, &newsid);
1161	if (length)
1162	goto out;
1163
1164	length = security_sid_to_context(newsid, &newcon, &len);
1165	if (length)
1166	goto out;
1167
1168	length = -ERANGE;
1169	if (len > SIMPLE_TRANSACTION_LIMIT) {
1170	pr_err("SELinux: %s: context size (%u) exceeds "
1171	"payload max\n", __func__, len);
1172	goto out;
1173	}
1174
1175	memcpy(buf, newcon, len);
1176	length = len;
1177	out:
1178	kfree(objp: newcon);
1179	kfree(objp: tcon);
1180	kfree(objp: scon);
1181	return length;
1182	}
1183
1184	static struct inode *sel_make_inode(struct super_block *sb, umode_t mode)
1185	{
1186	struct inode *ret = new_inode(sb);
1187
1188	if (ret) {
1189	ret->i_mode = mode;
1190	simple_inode_init_ts(inode: ret);
1191	}
1192	return ret;
1193	}
1194
1195	static ssize_t sel_read_bool(struct file *filep, char __user *buf,
1196	size_t count, loff_t *ppos)
1197	{
1198	struct selinux_fs_info *fsi = file_inode(f: filep)->i_sb->s_fs_info;
1199	char *page = NULL;
1200	ssize_t length;
1201	ssize_t ret;
1202	int cur_enforcing;
1203	unsigned index = file_inode(f: filep)->i_ino & SEL_INO_MASK;
1204	const char *name = filep->f_path.dentry->d_name.name;
1205
1206	mutex_lock(&selinux_state.policy_mutex);
1207
1208	ret = -EINVAL;
1209	if (index >= fsi->bool_num || strcmp(name,
1210	fsi->bool_pending_names[index]))
1211	goto out_unlock;
1212
1213	ret = -ENOMEM;
1214	page = (char *)get_zeroed_page(GFP_KERNEL);
1215	if (!page)
1216	goto out_unlock;
1217
1218	cur_enforcing = security_get_bool_value(index);
1219	if (cur_enforcing < 0) {
1220	ret = cur_enforcing;
1221	goto out_unlock;
1222	}
1223	length = scnprintf(buf: page, PAGE_SIZE, fmt: "%d %d", cur_enforcing,
1224	fsi->bool_pending_values[index]);
1225	mutex_unlock(&selinux_state.policy_mutex);
1226	ret = simple_read_from_buffer(to: buf, count, ppos, from: page, available: length);
1227	out_free:
1228	free_page((unsigned long)page);
1229	return ret;
1230
1231	out_unlock:
1232	mutex_unlock(&selinux_state.policy_mutex);
1233	goto out_free;
1234	}
1235
1236	static ssize_t sel_write_bool(struct file *filep, const char __user *buf,
1237	size_t count, loff_t *ppos)
1238	{
1239	struct selinux_fs_info *fsi = file_inode(f: filep)->i_sb->s_fs_info;
1240	char *page = NULL;
1241	ssize_t length;
1242	int new_value;
1243	unsigned index = file_inode(f: filep)->i_ino & SEL_INO_MASK;
1244	const char *name = filep->f_path.dentry->d_name.name;
1245
1246	if (count >= PAGE_SIZE)
1247	return -ENOMEM;
1248
1249	/* No partial writes. */
1250	if (*ppos != 0)
1251	return -EINVAL;
1252
1253	page = memdup_user_nul(buf, count);
1254	if (IS_ERR(ptr: page))
1255	return PTR_ERR(ptr: page);
1256
1257	mutex_lock(&selinux_state.policy_mutex);
1258
1259	length = avc_has_perm(current_sid(), SECINITSID_SECURITY,
1260	SECCLASS_SECURITY, SECURITY__SETBOOL,
1261	NULL);
1262	if (length)
1263	goto out;
1264
1265	length = -EINVAL;
1266	if (index >= fsi->bool_num || strcmp(name,
1267	fsi->bool_pending_names[index]))
1268	goto out;
1269
1270	length = -EINVAL;
1271	if (sscanf(page, "%d", &new_value) != 1)
1272	goto out;
1273
1274	if (new_value)
1275	new_value = 1;
1276
1277	fsi->bool_pending_values[index] = new_value;
1278	length = count;
1279
1280	out:
1281	mutex_unlock(&selinux_state.policy_mutex);
1282	kfree(objp: page);
1283	return length;
1284	}
1285
1286	static const struct file_operations sel_bool_ops = {
1287	.read = sel_read_bool,
1288	.write = sel_write_bool,
1289	.llseek = generic_file_llseek,
1290	};
1291
1292	static ssize_t sel_commit_bools_write(struct file *filep,
1293	const char __user *buf,
1294	size_t count, loff_t *ppos)
1295	{
1296	struct selinux_fs_info *fsi = file_inode(f: filep)->i_sb->s_fs_info;
1297	char *page = NULL;
1298	ssize_t length;
1299	int new_value;
1300
1301	if (count >= PAGE_SIZE)
1302	return -ENOMEM;
1303
1304	/* No partial writes. */
1305	if (*ppos != 0)
1306	return -EINVAL;
1307
1308	page = memdup_user_nul(buf, count);
1309	if (IS_ERR(ptr: page))
1310	return PTR_ERR(ptr: page);
1311
1312	mutex_lock(&selinux_state.policy_mutex);
1313
1314	length = avc_has_perm(current_sid(), SECINITSID_SECURITY,
1315	SECCLASS_SECURITY, SECURITY__SETBOOL,
1316	NULL);
1317	if (length)
1318	goto out;
1319
1320	length = -EINVAL;
1321	if (sscanf(page, "%d", &new_value) != 1)
1322	goto out;
1323
1324	length = 0;
1325	if (new_value && fsi->bool_pending_values)
1326	length = security_set_bools(fsi->bool_num,
1327	fsi->bool_pending_values);
1328
1329	if (!length)
1330	length = count;
1331
1332	out:
1333	mutex_unlock(&selinux_state.policy_mutex);
1334	kfree(objp: page);
1335	return length;
1336	}
1337
1338	static const struct file_operations sel_commit_bools_ops = {
1339	.write = sel_commit_bools_write,
1340	.llseek = generic_file_llseek,
1341	};
1342
1343	static int sel_make_bools(struct selinux_policy *newpolicy, struct dentry *bool_dir,
1344	unsigned int *bool_num, char ***bool_pending_names,
1345	int **bool_pending_values)
1346	{
1347	int ret;
1348	char **names, *page;
1349	u32 i, num;
1350
1351	page = (char *)get_zeroed_page(GFP_KERNEL);
1352	if (!page)
1353	return -ENOMEM;
1354
1355	ret = security_get_bools(newpolicy, &num, &names, bool_pending_values);
1356	if (ret)
1357	goto out;
1358
1359	*bool_num = num;
1360	*bool_pending_names = names;
1361
1362	for (i = 0; i < num; i++) {
1363	struct dentry *dentry;
1364	struct inode *inode;
1365	struct inode_security_struct *isec;
1366	ssize_t len;
1367	u32 sid;
1368
1369	len = snprintf(buf: page, PAGE_SIZE, fmt: "/%s/%s", BOOL_DIR_NAME, names[i]);
1370	if (len >= PAGE_SIZE) {
1371	ret = -ENAMETOOLONG;
1372	break;
1373	}
1374	dentry = d_alloc_name(bool_dir, names[i]);
1375	if (!dentry) {
1376	ret = -ENOMEM;
1377	break;
1378	}
1379
1380	inode = sel_make_inode(sb: bool_dir->d_sb, S_IFREG | S_IRUGO | S_IWUSR);
1381	if (!inode) {
1382	dput(dentry);
1383	ret = -ENOMEM;
1384	break;
1385	}
1386
1387	isec = selinux_inode(inode);
1388	ret = selinux_policy_genfs_sid(newpolicy, "selinuxfs", page,
1389	SECCLASS_FILE, &sid);
1390	if (ret) {
1391	pr_warn_ratelimited("SELinux: no sid found, defaulting to security isid for %s\n",
1392	page);
1393	sid = SECINITSID_SECURITY;
1394	}
1395
1396	isec->sid = sid;
1397	isec->initialized = LABEL_INITIALIZED;
1398	inode->i_fop = &sel_bool_ops;
1399	inode->i_ino = i|SEL_BOOL_INO_OFFSET;
1400	d_add(dentry, inode);
1401	}
1402	out:
1403	free_page((unsigned long)page);
1404	return ret;
1405	}
1406
1407	static ssize_t sel_read_avc_cache_threshold(struct file *filp, char __user *buf,
1408	size_t count, loff_t *ppos)
1409	{
1410	char tmpbuf[TMPBUFLEN];
1411	ssize_t length;
1412
1413	length = scnprintf(buf: tmpbuf, TMPBUFLEN, fmt: "%u",
1414	avc_get_cache_threshold());
1415	return simple_read_from_buffer(to: buf, count, ppos, from: tmpbuf, available: length);
1416	}
1417
1418	static ssize_t sel_write_avc_cache_threshold(struct file *file,
1419	const char __user *buf,
1420	size_t count, loff_t *ppos)
1421
1422	{
1423	char *page;
1424	ssize_t ret;
1425	unsigned int new_value;
1426
1427	ret = avc_has_perm(current_sid(), SECINITSID_SECURITY,
1428	SECCLASS_SECURITY, SECURITY__SETSECPARAM,
1429	NULL);
1430	if (ret)
1431	return ret;
1432
1433	if (count >= PAGE_SIZE)
1434	return -ENOMEM;
1435
1436	/* No partial writes. */
1437	if (*ppos != 0)
1438	return -EINVAL;
1439
1440	page = memdup_user_nul(buf, count);
1441	if (IS_ERR(ptr: page))
1442	return PTR_ERR(ptr: page);
1443
1444	ret = -EINVAL;
1445	if (sscanf(page, "%u", &new_value) != 1)
1446	goto out;
1447
1448	avc_set_cache_threshold(new_value);
1449
1450	ret = count;
1451	out:
1452	kfree(objp: page);
1453	return ret;
1454	}
1455
1456	static ssize_t sel_read_avc_hash_stats(struct file *filp, char __user *buf,
1457	size_t count, loff_t *ppos)
1458	{
1459	char *page;
1460	ssize_t length;
1461
1462	page = (char *)__get_free_page(GFP_KERNEL);
1463	if (!page)
1464	return -ENOMEM;
1465
1466	length = avc_get_hash_stats(page);
1467	if (length >= 0)
1468	length = simple_read_from_buffer(to: buf, count, ppos, from: page, available: length);
1469	free_page((unsigned long)page);
1470
1471	return length;
1472	}
1473
1474	static ssize_t sel_read_sidtab_hash_stats(struct file *filp, char __user *buf,
1475	size_t count, loff_t *ppos)
1476	{
1477	char *page;
1478	ssize_t length;
1479
1480	page = (char *)__get_free_page(GFP_KERNEL);
1481	if (!page)
1482	return -ENOMEM;
1483
1484	length = security_sidtab_hash_stats(page);
1485	if (length >= 0)
1486	length = simple_read_from_buffer(to: buf, count, ppos, from: page,
1487	available: length);
1488	free_page((unsigned long)page);
1489
1490	return length;
1491	}
1492
1493	static const struct file_operations sel_sidtab_hash_stats_ops = {
1494	.read = sel_read_sidtab_hash_stats,
1495	.llseek = generic_file_llseek,
1496	};
1497
1498	static const struct file_operations sel_avc_cache_threshold_ops = {
1499	.read = sel_read_avc_cache_threshold,
1500	.write = sel_write_avc_cache_threshold,
1501	.llseek = generic_file_llseek,
1502	};
1503
1504	static const struct file_operations sel_avc_hash_stats_ops = {
1505	.read = sel_read_avc_hash_stats,
1506	.llseek = generic_file_llseek,
1507	};
1508
1509	#ifdef CONFIG_SECURITY_SELINUX_AVC_STATS
1510	static struct avc_cache_stats *sel_avc_get_stat_idx(loff_t *idx)
1511	{
1512	int cpu;
1513
1514	for (cpu = *idx; cpu < nr_cpu_ids; ++cpu) {
1515	if (!cpu_possible(cpu))
1516	continue;
1517	*idx = cpu + 1;
1518	return &per_cpu(avc_cache_stats, cpu);
1519	}
1520	(*idx)++;
1521	return NULL;
1522	}
1523
1524	static void *sel_avc_stats_seq_start(struct seq_file *seq, loff_t *pos)
1525	{
1526	loff_t n = *pos - 1;
1527
1528	if (*pos == 0)
1529	return SEQ_START_TOKEN;
1530
1531	return sel_avc_get_stat_idx(idx: &n);
1532	}
1533
1534	static void *sel_avc_stats_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1535	{
1536	return sel_avc_get_stat_idx(idx: pos);
1537	}
1538
1539	static int sel_avc_stats_seq_show(struct seq_file *seq, void *v)
1540	{
1541	struct avc_cache_stats *st = v;
1542
1543	if (v == SEQ_START_TOKEN) {
1544	seq_puts(m: seq,
1545	s: "lookups hits misses allocations reclaims frees\n");
1546	} else {
1547	unsigned int lookups = st->lookups;
1548	unsigned int misses = st->misses;
1549	unsigned int hits = lookups - misses;
1550	seq_printf(m: seq, fmt: "%u %u %u %u %u %u\n", lookups,
1551	hits, misses, st->allocations,
1552	st->reclaims, st->frees);
1553	}
1554	return 0;
1555	}
1556
1557	static void sel_avc_stats_seq_stop(struct seq_file *seq, void *v)
1558	{ }
1559
1560	static const struct seq_operations sel_avc_cache_stats_seq_ops = {
1561	.start = sel_avc_stats_seq_start,
1562	.next = sel_avc_stats_seq_next,
1563	.show = sel_avc_stats_seq_show,
1564	.stop = sel_avc_stats_seq_stop,
1565	};
1566
1567	static int sel_open_avc_cache_stats(struct inode *inode, struct file *file)
1568	{
1569	return seq_open(file, &sel_avc_cache_stats_seq_ops);
1570	}
1571
1572	static const struct file_operations sel_avc_cache_stats_ops = {
1573	.open = sel_open_avc_cache_stats,
1574	.read = seq_read,
1575	.llseek = seq_lseek,
1576	.release = seq_release,
1577	};
1578	#endif
1579
1580	static int sel_make_avc_files(struct dentry *dir)
1581	{
1582	struct super_block *sb = dir->d_sb;
1583	struct selinux_fs_info *fsi = sb->s_fs_info;
1584	unsigned int i;
1585	static const struct tree_descr files[] = {
1586	{ "cache_threshold",
1587	&sel_avc_cache_threshold_ops, S_IRUGO|S_IWUSR },
1588	{ "hash_stats", &sel_avc_hash_stats_ops, S_IRUGO },
1589	#ifdef CONFIG_SECURITY_SELINUX_AVC_STATS
1590	{ "cache_stats", &sel_avc_cache_stats_ops, S_IRUGO },
1591	#endif
1592	};
1593
1594	for (i = 0; i < ARRAY_SIZE(files); i++) {
1595	struct inode *inode;
1596	struct dentry *dentry;
1597
1598	dentry = d_alloc_name(dir, files[i].name);
1599	if (!dentry)
1600	return -ENOMEM;
1601
1602	inode = sel_make_inode(sb: dir->d_sb, S_IFREG|files[i].mode);
1603	if (!inode) {
1604	dput(dentry);
1605	return -ENOMEM;
1606	}
1607
1608	inode->i_fop = files[i].ops;
1609	inode->i_ino = ++fsi->last_ino;
1610	d_add(dentry, inode);
1611	}
1612
1613	return 0;
1614	}
1615
1616	static int sel_make_ss_files(struct dentry *dir)
1617	{
1618	struct super_block *sb = dir->d_sb;
1619	struct selinux_fs_info *fsi = sb->s_fs_info;
1620	unsigned int i;
1621	static const struct tree_descr files[] = {
1622	{ "sidtab_hash_stats", &sel_sidtab_hash_stats_ops, S_IRUGO },
1623	};
1624
1625	for (i = 0; i < ARRAY_SIZE(files); i++) {
1626	struct inode *inode;
1627	struct dentry *dentry;
1628
1629	dentry = d_alloc_name(dir, files[i].name);
1630	if (!dentry)
1631	return -ENOMEM;
1632
1633	inode = sel_make_inode(sb: dir->d_sb, S_IFREG|files[i].mode);
1634	if (!inode) {
1635	dput(dentry);
1636	return -ENOMEM;
1637	}
1638
1639	inode->i_fop = files[i].ops;
1640	inode->i_ino = ++fsi->last_ino;
1641	d_add(dentry, inode);
1642	}
1643
1644	return 0;
1645	}
1646
1647	static ssize_t sel_read_initcon(struct file *file, char __user *buf,
1648	size_t count, loff_t *ppos)
1649	{
1650	char *con;
1651	u32 sid, len;
1652	ssize_t ret;
1653
1654	sid = file_inode(f: file)->i_ino&SEL_INO_MASK;
1655	ret = security_sid_to_context(sid, &con, &len);
1656	if (ret)
1657	return ret;
1658
1659	ret = simple_read_from_buffer(to: buf, count, ppos, from: con, available: len);
1660	kfree(objp: con);
1661	return ret;
1662	}
1663
1664	static const struct file_operations sel_initcon_ops = {
1665	.read = sel_read_initcon,
1666	.llseek = generic_file_llseek,
1667	};
1668
1669	static int sel_make_initcon_files(struct dentry *dir)
1670	{
1671	unsigned int i;
1672
1673	for (i = 1; i <= SECINITSID_NUM; i++) {
1674	struct inode *inode;
1675	struct dentry *dentry;
1676	const char *s = security_get_initial_sid_context(i);
1677
1678	if (!s)
1679	continue;
1680	dentry = d_alloc_name(dir, s);
1681	if (!dentry)
1682	return -ENOMEM;
1683
1684	inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
1685	if (!inode) {
1686	dput(dentry);
1687	return -ENOMEM;
1688	}
1689
1690	inode->i_fop = &sel_initcon_ops;
1691	inode->i_ino = i|SEL_INITCON_INO_OFFSET;
1692	d_add(dentry, inode);
1693	}
1694
1695	return 0;
1696	}
1697
1698	static inline unsigned long sel_class_to_ino(u16 class)
1699	{
1700	return (class * (SEL_VEC_MAX + 1)) | SEL_CLASS_INO_OFFSET;
1701	}
1702
1703	static inline u16 sel_ino_to_class(unsigned long ino)
1704	{
1705	return (ino & SEL_INO_MASK) / (SEL_VEC_MAX + 1);
1706	}
1707
1708	static inline unsigned long sel_perm_to_ino(u16 class, u32 perm)
1709	{
1710	return (class * (SEL_VEC_MAX + 1) + perm) | SEL_CLASS_INO_OFFSET;
1711	}
1712
1713	static inline u32 sel_ino_to_perm(unsigned long ino)
1714	{
1715	return (ino & SEL_INO_MASK) % (SEL_VEC_MAX + 1);
1716	}
1717
1718	static ssize_t sel_read_class(struct file *file, char __user *buf,
1719	size_t count, loff_t *ppos)
1720	{
1721	unsigned long ino = file_inode(f: file)->i_ino;
1722	char res[TMPBUFLEN];
1723	ssize_t len = scnprintf(buf: res, size: sizeof(res), fmt: "%d", sel_ino_to_class(ino));
1724	return simple_read_from_buffer(to: buf, count, ppos, from: res, available: len);
1725	}
1726
1727	static const struct file_operations sel_class_ops = {
1728	.read = sel_read_class,
1729	.llseek = generic_file_llseek,
1730	};
1731
1732	static ssize_t sel_read_perm(struct file *file, char __user *buf,
1733	size_t count, loff_t *ppos)
1734	{
1735	unsigned long ino = file_inode(f: file)->i_ino;
1736	char res[TMPBUFLEN];
1737	ssize_t len = scnprintf(buf: res, size: sizeof(res), fmt: "%d", sel_ino_to_perm(ino));
1738	return simple_read_from_buffer(to: buf, count, ppos, from: res, available: len);
1739	}
1740
1741	static const struct file_operations sel_perm_ops = {
1742	.read = sel_read_perm,
1743	.llseek = generic_file_llseek,
1744	};
1745
1746	static ssize_t sel_read_policycap(struct file *file, char __user *buf,
1747	size_t count, loff_t *ppos)
1748	{
1749	int value;
1750	char tmpbuf[TMPBUFLEN];
1751	ssize_t length;
1752	unsigned long i_ino = file_inode(f: file)->i_ino;
1753
1754	value = security_policycap_supported(i_ino & SEL_INO_MASK);
1755	length = scnprintf(buf: tmpbuf, TMPBUFLEN, fmt: "%d", value);
1756
1757	return simple_read_from_buffer(to: buf, count, ppos, from: tmpbuf, available: length);
1758	}
1759
1760	static const struct file_operations sel_policycap_ops = {
1761	.read = sel_read_policycap,
1762	.llseek = generic_file_llseek,
1763	};
1764
1765	static int sel_make_perm_files(struct selinux_policy *newpolicy,
1766	char *objclass, int classvalue,
1767	struct dentry *dir)
1768	{
1769	u32 i, nperms;
1770	int rc;
1771	char **perms;
1772
1773	rc = security_get_permissions(newpolicy, objclass, &perms, &nperms);
1774	if (rc)
1775	return rc;
1776
1777	for (i = 0; i < nperms; i++) {
1778	struct inode *inode;
1779	struct dentry *dentry;
1780
1781	rc = -ENOMEM;
1782	dentry = d_alloc_name(dir, perms[i]);
1783	if (!dentry)
1784	goto out;
1785
1786	rc = -ENOMEM;
1787	inode = sel_make_inode(sb: dir->d_sb, S_IFREG|S_IRUGO);
1788	if (!inode) {
1789	dput(dentry);
1790	goto out;
1791	}
1792
1793	inode->i_fop = &sel_perm_ops;
1794	/* i+1 since perm values are 1-indexed */
1795	inode->i_ino = sel_perm_to_ino(class: classvalue, perm: i + 1);
1796	d_add(dentry, inode);
1797	}
1798	rc = 0;
1799	out:
1800	for (i = 0; i < nperms; i++)
1801	kfree(objp: perms[i]);
1802	kfree(objp: perms);
1803	return rc;
1804	}
1805
1806	static int sel_make_class_dir_entries(struct selinux_policy *newpolicy,
1807	char *classname, int index,
1808	struct dentry *dir)
1809	{
1810	struct super_block *sb = dir->d_sb;
1811	struct selinux_fs_info *fsi = sb->s_fs_info;
1812	struct dentry *dentry = NULL;
1813	struct inode *inode = NULL;
1814
1815	dentry = d_alloc_name(dir, "index");
1816	if (!dentry)
1817	return -ENOMEM;
1818
1819	inode = sel_make_inode(sb: dir->d_sb, S_IFREG|S_IRUGO);
1820	if (!inode) {
1821	dput(dentry);
1822	return -ENOMEM;
1823	}
1824
1825	inode->i_fop = &sel_class_ops;
1826	inode->i_ino = sel_class_to_ino(class: index);
1827	d_add(dentry, inode);
1828
1829	dentry = sel_make_dir(dir, name: "perms", ino: &fsi->last_class_ino);
1830	if (IS_ERR(ptr: dentry))
1831	return PTR_ERR(ptr: dentry);
1832
1833	return sel_make_perm_files(newpolicy, objclass: classname, classvalue: index, dir: dentry);
1834	}
1835
1836	static int sel_make_classes(struct selinux_policy *newpolicy,
1837	struct dentry *class_dir,
1838	unsigned long *last_class_ino)
1839	{
1840	u32 i, nclasses;
1841	int rc;
1842	char **classes;
1843
1844	rc = security_get_classes(newpolicy, &classes, &nclasses);
1845	if (rc)
1846	return rc;
1847
1848	/* +2 since classes are 1-indexed */
1849	*last_class_ino = sel_class_to_ino(class: nclasses + 2);
1850
1851	for (i = 0; i < nclasses; i++) {
1852	struct dentry *class_name_dir;
1853
1854	class_name_dir = sel_make_dir(dir: class_dir, name: classes[i],
1855	ino: last_class_ino);
1856	if (IS_ERR(ptr: class_name_dir)) {
1857	rc = PTR_ERR(ptr: class_name_dir);
1858	goto out;
1859	}
1860
1861	/* i+1 since class values are 1-indexed */
1862	rc = sel_make_class_dir_entries(newpolicy, classname: classes[i], index: i + 1,
1863	dir: class_name_dir);
1864	if (rc)
1865	goto out;
1866	}
1867	rc = 0;
1868	out:
1869	for (i = 0; i < nclasses; i++)
1870	kfree(objp: classes[i]);
1871	kfree(objp: classes);
1872	return rc;
1873	}
1874
1875	static int sel_make_policycap(struct selinux_fs_info *fsi)
1876	{
1877	unsigned int iter;
1878	struct dentry *dentry = NULL;
1879	struct inode *inode = NULL;
1880
1881	for (iter = 0; iter <= POLICYDB_CAP_MAX; iter++) {
1882	if (iter < ARRAY_SIZE(selinux_policycap_names))
1883	dentry = d_alloc_name(fsi->policycap_dir,
1884	selinux_policycap_names[iter]);
1885	else
1886	dentry = d_alloc_name(fsi->policycap_dir, "unknown");
1887
1888	if (dentry == NULL)
1889	return -ENOMEM;
1890
1891	inode = sel_make_inode(fsi->sb, S_IFREG | 0444);
1892	if (inode == NULL) {
1893	dput(dentry);
1894	return -ENOMEM;
1895	}
1896
1897	inode->i_fop = &sel_policycap_ops;
1898	inode->i_ino = iter | SEL_POLICYCAP_INO_OFFSET;
1899	d_add(dentry, inode);
1900	}
1901
1902	return 0;
1903	}
1904
1905	static struct dentry *sel_make_dir(struct dentry *dir, const char *name,
1906	unsigned long *ino)
1907	{
1908	struct dentry *dentry = d_alloc_name(dir, name);
1909	struct inode *inode;
1910
1911	if (!dentry)
1912	return ERR_PTR(error: -ENOMEM);
1913
1914	inode = sel_make_inode(sb: dir->d_sb, S_IFDIR | S_IRUGO | S_IXUGO);
1915	if (!inode) {
1916	dput(dentry);
1917	return ERR_PTR(error: -ENOMEM);
1918	}
1919
1920	inode->i_op = &simple_dir_inode_operations;
1921	inode->i_fop = &simple_dir_operations;
1922	inode->i_ino = ++(*ino);
1923	/* directory inodes start off with i_nlink == 2 (for "." entry) */
1924	inc_nlink(inode);
1925	d_add(dentry, inode);
1926	/* bump link count on parent directory, too */
1927	inc_nlink(inode: d_inode(dentry: dir));
1928
1929	return dentry;
1930	}
1931
1932	static int reject_all(struct mnt_idmap *idmap, struct inode *inode, int mask)
1933	{
1934	return -EPERM; // no access for anyone, root or no root.
1935	}
1936
1937	static const struct inode_operations swapover_dir_inode_operations = {
1938	.lookup = simple_lookup,
1939	.permission = reject_all,
1940	};
1941
1942	static struct dentry *sel_make_swapover_dir(struct super_block *sb,
1943	unsigned long *ino)
1944	{
1945	struct dentry *dentry = d_alloc_name(sb->s_root, ".swapover");
1946	struct inode *inode;
1947
1948	if (!dentry)
1949	return ERR_PTR(error: -ENOMEM);
1950
1951	inode = sel_make_inode(sb, S_IFDIR);
1952	if (!inode) {
1953	dput(dentry);
1954	return ERR_PTR(error: -ENOMEM);
1955	}
1956
1957	inode->i_op = &swapover_dir_inode_operations;
1958	inode->i_ino = ++(*ino);
1959	/* directory inodes start off with i_nlink == 2 (for "." entry) */
1960	inc_nlink(inode);
1961	inode_lock(inode: sb->s_root->d_inode);
1962	d_add(dentry, inode);
1963	inc_nlink(inode: sb->s_root->d_inode);
1964	inode_unlock(inode: sb->s_root->d_inode);
1965	return dentry;
1966	}
1967
1968	#define NULL_FILE_NAME "null"
1969
1970	static int sel_fill_super(struct super_block *sb, struct fs_context *fc)
1971	{
1972	struct selinux_fs_info *fsi;
1973	int ret;
1974	struct dentry *dentry;
1975	struct inode *inode;
1976	struct inode_security_struct *isec;
1977
1978	static const struct tree_descr selinux_files[] = {
1979	[SEL_LOAD] = {"load", &sel_load_ops, S_IRUSR|S_IWUSR},
1980	[SEL_ENFORCE] = {.name: "enforce", .ops: &sel_enforce_ops, S_IRUGO|S_IWUSR},
1981	[SEL_CONTEXT] = {.name: "context", .ops: &transaction_ops, S_IRUGO|S_IWUGO},
1982	[SEL_ACCESS] = {.name: "access", .ops: &transaction_ops, S_IRUGO|S_IWUGO},
1983	[SEL_CREATE] = {.name: "create", .ops: &transaction_ops, S_IRUGO|S_IWUGO},
1984	[SEL_RELABEL] = {.name: "relabel", .ops: &transaction_ops, S_IRUGO|S_IWUGO},
1985	[SEL_USER] = {.name: "user", .ops: &transaction_ops, S_IRUGO|S_IWUGO},
1986	[SEL_POLICYVERS] = {.name: "policyvers", .ops: &sel_policyvers_ops, S_IRUGO},
1987	[SEL_COMMIT_BOOLS] = {.name: "commit_pending_bools", .ops: &sel_commit_bools_ops, S_IWUSR},
1988	[SEL_MLS] = {.name: "mls", .ops: &sel_mls_ops, S_IRUGO},
1989	[SEL_DISABLE] = {.name: "disable", .ops: &sel_disable_ops, S_IWUSR},
1990	[SEL_MEMBER] = {.name: "member", .ops: &transaction_ops, S_IRUGO|S_IWUGO},
1991	[SEL_CHECKREQPROT] = {.name: "checkreqprot", .ops: &sel_checkreqprot_ops, S_IRUGO|S_IWUSR},
1992	[SEL_REJECT_UNKNOWN] = {.name: "reject_unknown", .ops: &sel_handle_unknown_ops, S_IRUGO},
1993	[SEL_DENY_UNKNOWN] = {.name: "deny_unknown", .ops: &sel_handle_unknown_ops, S_IRUGO},
1994	[SEL_STATUS] = {.name: "status", .ops: &sel_handle_status_ops, S_IRUGO},
1995	[SEL_POLICY] = {.name: "policy", .ops: &sel_policy_ops, S_IRUGO},
1996	[SEL_VALIDATE_TRANS] = {.name: "validatetrans", .ops: &sel_transition_ops,
1997	S_IWUGO},
1998	/* last one */ {""}
1999	};
2000
2001	ret = selinux_fs_info_create(sb);
2002	if (ret)
2003	goto err;
2004
2005	ret = simple_fill_super(sb, SELINUX_MAGIC, selinux_files);
2006	if (ret)
2007	goto err;
2008
2009	fsi = sb->s_fs_info;
2010	fsi->bool_dir = sel_make_dir(dir: sb->s_root, BOOL_DIR_NAME, ino: &fsi->last_ino);
2011	if (IS_ERR(ptr: fsi->bool_dir)) {
2012	ret = PTR_ERR(ptr: fsi->bool_dir);
2013	fsi->bool_dir = NULL;
2014	goto err;
2015	}
2016
2017	ret = -ENOMEM;
2018	dentry = d_alloc_name(sb->s_root, NULL_FILE_NAME);
2019	if (!dentry)
2020	goto err;
2021
2022	ret = -ENOMEM;
2023	inode = sel_make_inode(sb, S_IFCHR | S_IRUGO | S_IWUGO);
2024	if (!inode) {
2025	dput(dentry);
2026	goto err;
2027	}
2028
2029	inode->i_ino = ++fsi->last_ino;
2030	isec = selinux_inode(inode);
2031	isec->sid = SECINITSID_DEVNULL;
2032	isec->sclass = SECCLASS_CHR_FILE;
2033	isec->initialized = LABEL_INITIALIZED;
2034
2035	init_special_inode(inode, S_IFCHR | S_IRUGO | S_IWUGO, MKDEV(MEM_MAJOR, 3));
2036	d_add(dentry, inode);
2037
2038	dentry = sel_make_dir(dir: sb->s_root, name: "avc", ino: &fsi->last_ino);
2039	if (IS_ERR(ptr: dentry)) {
2040	ret = PTR_ERR(ptr: dentry);
2041	goto err;
2042	}
2043
2044	ret = sel_make_avc_files(dir: dentry);
2045	if (ret)
2046	goto err;
2047
2048	dentry = sel_make_dir(dir: sb->s_root, name: "ss", ino: &fsi->last_ino);
2049	if (IS_ERR(ptr: dentry)) {
2050	ret = PTR_ERR(ptr: dentry);
2051	goto err;
2052	}
2053
2054	ret = sel_make_ss_files(dir: dentry);
2055	if (ret)
2056	goto err;
2057
2058	dentry = sel_make_dir(dir: sb->s_root, name: "initial_contexts", ino: &fsi->last_ino);
2059	if (IS_ERR(ptr: dentry)) {
2060	ret = PTR_ERR(ptr: dentry);
2061	goto err;
2062	}
2063
2064	ret = sel_make_initcon_files(dir: dentry);
2065	if (ret)
2066	goto err;
2067
2068	fsi->class_dir = sel_make_dir(dir: sb->s_root, CLASS_DIR_NAME, ino: &fsi->last_ino);
2069	if (IS_ERR(ptr: fsi->class_dir)) {
2070	ret = PTR_ERR(ptr: fsi->class_dir);
2071	fsi->class_dir = NULL;
2072	goto err;
2073	}
2074
2075	fsi->policycap_dir = sel_make_dir(dir: sb->s_root, POLICYCAP_DIR_NAME,
2076	ino: &fsi->last_ino);
2077	if (IS_ERR(ptr: fsi->policycap_dir)) {
2078	ret = PTR_ERR(ptr: fsi->policycap_dir);
2079	fsi->policycap_dir = NULL;
2080	goto err;
2081	}
2082
2083	ret = sel_make_policycap(fsi);
2084	if (ret) {
2085	pr_err("SELinux: failed to load policy capabilities\n");
2086	goto err;
2087	}
2088
2089	return 0;
2090	err:
2091	pr_err("SELinux: %s: failed while creating inodes\n",
2092	__func__);
2093
2094	selinux_fs_info_free(sb);
2095
2096	return ret;
2097	}
2098
2099	static int sel_get_tree(struct fs_context *fc)
2100	{
2101	return get_tree_single(fc, fill_super: sel_fill_super);
2102	}
2103
2104	static const struct fs_context_operations sel_context_ops = {
2105	.get_tree = sel_get_tree,
2106	};
2107
2108	static int sel_init_fs_context(struct fs_context *fc)
2109	{
2110	fc->ops = &sel_context_ops;
2111	return 0;
2112	}
2113
2114	static void sel_kill_sb(struct super_block *sb)
2115	{
2116	selinux_fs_info_free(sb);
2117	kill_litter_super(sb);
2118	}
2119
2120	static struct file_system_type sel_fs_type = {
2121	.name = "selinuxfs",
2122	.init_fs_context = sel_init_fs_context,
2123	.kill_sb = sel_kill_sb,
2124	};
2125
2126	struct path selinux_null __ro_after_init;
2127
2128	static int __init init_sel_fs(void)
2129	{
2130	struct qstr null_name = QSTR_INIT(NULL_FILE_NAME,
2131	sizeof(NULL_FILE_NAME)-1);
2132	int err;
2133
2134	if (!selinux_enabled_boot)
2135	return 0;
2136
2137	err = sysfs_create_mount_point(parent_kobj: fs_kobj, name: "selinux");
2138	if (err)
2139	return err;
2140
2141	err = register_filesystem(&sel_fs_type);
2142	if (err) {
2143	sysfs_remove_mount_point(parent_kobj: fs_kobj, name: "selinux");
2144	return err;
2145	}
2146
2147	selinux_null.mnt = kern_mount(&sel_fs_type);
2148	if (IS_ERR(ptr: selinux_null.mnt)) {
2149	pr_err("selinuxfs: could not mount!\n");
2150	err = PTR_ERR(ptr: selinux_null.mnt);
2151	selinux_null.mnt = NULL;
2152	return err;
2153	}
2154
2155	selinux_null.dentry = d_hash_and_lookup(selinux_null.mnt->mnt_root,
2156	&null_name);
2157	if (IS_ERR(ptr: selinux_null.dentry)) {
2158	pr_err("selinuxfs: could not lookup null!\n");
2159	err = PTR_ERR(ptr: selinux_null.dentry);
2160	selinux_null.dentry = NULL;
2161	return err;
2162	}
2163
2164	return err;
2165	}
2166
2167	__initcall(init_sel_fs);
2168