1 | // SPDX-License-Identifier: GPL-2.0 |
2 | #define _GNU_SOURCE |
3 | #define |
4 | |
5 | #include <errno.h> |
6 | #include <inttypes.h> |
7 | #include <limits.h> |
8 | #include <linux/falloc.h> |
9 | #include <fcntl.h> |
10 | #include <linux/memfd.h> |
11 | #include <sched.h> |
12 | #include <stdio.h> |
13 | #include <stdlib.h> |
14 | #include <signal.h> |
15 | #include <string.h> |
16 | #include <sys/mman.h> |
17 | #include <sys/stat.h> |
18 | #include <sys/syscall.h> |
19 | #include <sys/wait.h> |
20 | #include <unistd.h> |
21 | #include <ctype.h> |
22 | |
23 | #include "common.h" |
24 | |
25 | #define MEMFD_STR "memfd:" |
26 | #define MEMFD_HUGE_STR "memfd-hugetlb:" |
27 | #define SHARED_FT_STR "(shared file-table)" |
28 | |
29 | #define MFD_DEF_SIZE 8192 |
30 | #define STACK_SIZE 65536 |
31 | |
32 | #define F_SEAL_EXEC 0x0020 |
33 | |
34 | #define F_WX_SEALS (F_SEAL_SHRINK | \ |
35 | F_SEAL_GROW | \ |
36 | F_SEAL_WRITE | \ |
37 | F_SEAL_FUTURE_WRITE | \ |
38 | F_SEAL_EXEC) |
39 | |
40 | #define MFD_NOEXEC_SEAL 0x0008U |
41 | |
42 | /* |
43 | * Default is not to test hugetlbfs |
44 | */ |
45 | static size_t mfd_def_size = MFD_DEF_SIZE; |
46 | static const char *memfd_str = MEMFD_STR; |
47 | static int newpid_thread_fn2(void *arg); |
48 | static void join_newpid_thread(pid_t pid); |
49 | |
50 | static ssize_t fd2name(int fd, char *buf, size_t bufsize) |
51 | { |
52 | char buf1[PATH_MAX]; |
53 | int size; |
54 | ssize_t nbytes; |
55 | |
56 | size = snprintf(buf1, PATH_MAX, "/proc/self/fd/%d" , fd); |
57 | if (size < 0) { |
58 | printf("snprintf(%d) failed on %m\n" , fd); |
59 | abort(); |
60 | } |
61 | |
62 | /* |
63 | * reserver one byte for string termination. |
64 | */ |
65 | nbytes = readlink(buf1, buf, bufsize-1); |
66 | if (nbytes == -1) { |
67 | printf("readlink(%s) failed %m\n" , buf1); |
68 | abort(); |
69 | } |
70 | buf[nbytes] = '\0'; |
71 | return nbytes; |
72 | } |
73 | |
74 | static int mfd_assert_new(const char *name, loff_t sz, unsigned int flags) |
75 | { |
76 | int r, fd; |
77 | |
78 | fd = sys_memfd_create(name, flags); |
79 | if (fd < 0) { |
80 | printf("memfd_create(\"%s\", %u) failed: %m\n" , |
81 | name, flags); |
82 | abort(); |
83 | } |
84 | |
85 | r = ftruncate(fd, sz); |
86 | if (r < 0) { |
87 | printf("ftruncate(%llu) failed: %m\n" , (unsigned long long)sz); |
88 | abort(); |
89 | } |
90 | |
91 | return fd; |
92 | } |
93 | |
94 | static void sysctl_assert_write(const char *val) |
95 | { |
96 | int fd = open("/proc/sys/vm/memfd_noexec" , O_WRONLY | O_CLOEXEC); |
97 | |
98 | if (fd < 0) { |
99 | printf("open sysctl failed: %m\n" ); |
100 | abort(); |
101 | } |
102 | |
103 | if (write(fd, val, strlen(val)) < 0) { |
104 | printf("write sysctl %s failed: %m\n" , val); |
105 | abort(); |
106 | } |
107 | } |
108 | |
109 | static void sysctl_fail_write(const char *val) |
110 | { |
111 | int fd = open("/proc/sys/vm/memfd_noexec" , O_WRONLY | O_CLOEXEC); |
112 | |
113 | if (fd < 0) { |
114 | printf("open sysctl failed: %m\n" ); |
115 | abort(); |
116 | } |
117 | |
118 | if (write(fd, val, strlen(val)) >= 0) { |
119 | printf("write sysctl %s succeeded, but failure expected\n" , |
120 | val); |
121 | abort(); |
122 | } |
123 | } |
124 | |
125 | static void sysctl_assert_equal(const char *val) |
126 | { |
127 | char *p, buf[128] = {}; |
128 | int fd = open("/proc/sys/vm/memfd_noexec" , O_RDONLY | O_CLOEXEC); |
129 | |
130 | if (fd < 0) { |
131 | printf("open sysctl failed: %m\n" ); |
132 | abort(); |
133 | } |
134 | |
135 | if (read(fd, buf, sizeof(buf)) < 0) { |
136 | printf("read sysctl failed: %m\n" ); |
137 | abort(); |
138 | } |
139 | |
140 | /* Strip trailing whitespace. */ |
141 | p = buf; |
142 | while (!isspace(*p)) |
143 | p++; |
144 | *p = '\0'; |
145 | |
146 | if (strcmp(buf, val) != 0) { |
147 | printf("unexpected sysctl value: expected %s, got %s\n" , val, buf); |
148 | abort(); |
149 | } |
150 | } |
151 | |
152 | static int mfd_assert_reopen_fd(int fd_in) |
153 | { |
154 | int fd; |
155 | char path[100]; |
156 | |
157 | sprintf(path, "/proc/self/fd/%d" , fd_in); |
158 | |
159 | fd = open(path, O_RDWR); |
160 | if (fd < 0) { |
161 | printf("re-open of existing fd %d failed\n" , fd_in); |
162 | abort(); |
163 | } |
164 | |
165 | return fd; |
166 | } |
167 | |
168 | static void mfd_fail_new(const char *name, unsigned int flags) |
169 | { |
170 | int r; |
171 | |
172 | r = sys_memfd_create(name, flags); |
173 | if (r >= 0) { |
174 | printf("memfd_create(\"%s\", %u) succeeded, but failure expected\n" , |
175 | name, flags); |
176 | close(r); |
177 | abort(); |
178 | } |
179 | } |
180 | |
181 | static unsigned int mfd_assert_get_seals(int fd) |
182 | { |
183 | int r; |
184 | |
185 | r = fcntl(fd, F_GET_SEALS); |
186 | if (r < 0) { |
187 | printf("GET_SEALS(%d) failed: %m\n" , fd); |
188 | abort(); |
189 | } |
190 | |
191 | return (unsigned int)r; |
192 | } |
193 | |
194 | static void mfd_assert_has_seals(int fd, unsigned int seals) |
195 | { |
196 | char buf[PATH_MAX]; |
197 | int nbytes; |
198 | unsigned int s; |
199 | fd2name(fd, buf: buf, bufsize: PATH_MAX); |
200 | |
201 | s = mfd_assert_get_seals(fd); |
202 | if (s != seals) { |
203 | printf("%u != %u = GET_SEALS(%s)\n" , seals, s, buf); |
204 | abort(); |
205 | } |
206 | } |
207 | |
208 | static void mfd_assert_add_seals(int fd, unsigned int seals) |
209 | { |
210 | int r; |
211 | unsigned int s; |
212 | |
213 | s = mfd_assert_get_seals(fd); |
214 | r = fcntl(fd, F_ADD_SEALS, seals); |
215 | if (r < 0) { |
216 | printf("ADD_SEALS(%d, %u -> %u) failed: %m\n" , fd, s, seals); |
217 | abort(); |
218 | } |
219 | } |
220 | |
221 | static void mfd_fail_add_seals(int fd, unsigned int seals) |
222 | { |
223 | int r; |
224 | unsigned int s; |
225 | |
226 | r = fcntl(fd, F_GET_SEALS); |
227 | if (r < 0) |
228 | s = 0; |
229 | else |
230 | s = (unsigned int)r; |
231 | |
232 | r = fcntl(fd, F_ADD_SEALS, seals); |
233 | if (r >= 0) { |
234 | printf("ADD_SEALS(%d, %u -> %u) didn't fail as expected\n" , |
235 | fd, s, seals); |
236 | abort(); |
237 | } |
238 | } |
239 | |
240 | static void mfd_assert_size(int fd, size_t size) |
241 | { |
242 | struct stat st; |
243 | int r; |
244 | |
245 | r = fstat(fd, &st); |
246 | if (r < 0) { |
247 | printf("fstat(%d) failed: %m\n" , fd); |
248 | abort(); |
249 | } else if (st.st_size != size) { |
250 | printf("wrong file size %lld, but expected %lld\n" , |
251 | (long long)st.st_size, (long long)size); |
252 | abort(); |
253 | } |
254 | } |
255 | |
256 | static int mfd_assert_dup(int fd) |
257 | { |
258 | int r; |
259 | |
260 | r = dup(fd); |
261 | if (r < 0) { |
262 | printf("dup(%d) failed: %m\n" , fd); |
263 | abort(); |
264 | } |
265 | |
266 | return r; |
267 | } |
268 | |
269 | static void *mfd_assert_mmap_shared(int fd) |
270 | { |
271 | void *p; |
272 | |
273 | p = mmap(NULL, |
274 | mfd_def_size, |
275 | PROT_READ | PROT_WRITE, |
276 | MAP_SHARED, |
277 | fd, |
278 | 0); |
279 | if (p == MAP_FAILED) { |
280 | printf("mmap() failed: %m\n" ); |
281 | abort(); |
282 | } |
283 | |
284 | return p; |
285 | } |
286 | |
287 | static void *mfd_assert_mmap_private(int fd) |
288 | { |
289 | void *p; |
290 | |
291 | p = mmap(NULL, |
292 | mfd_def_size, |
293 | PROT_READ, |
294 | MAP_PRIVATE, |
295 | fd, |
296 | 0); |
297 | if (p == MAP_FAILED) { |
298 | printf("mmap() failed: %m\n" ); |
299 | abort(); |
300 | } |
301 | |
302 | return p; |
303 | } |
304 | |
305 | static int mfd_assert_open(int fd, int flags, mode_t mode) |
306 | { |
307 | char buf[512]; |
308 | int r; |
309 | |
310 | sprintf(buf, "/proc/self/fd/%d" , fd); |
311 | r = open(buf, flags, mode); |
312 | if (r < 0) { |
313 | printf("open(%s) failed: %m\n" , buf); |
314 | abort(); |
315 | } |
316 | |
317 | return r; |
318 | } |
319 | |
320 | static void mfd_fail_open(int fd, int flags, mode_t mode) |
321 | { |
322 | char buf[512]; |
323 | int r; |
324 | |
325 | sprintf(buf, "/proc/self/fd/%d" , fd); |
326 | r = open(buf, flags, mode); |
327 | if (r >= 0) { |
328 | printf("open(%s) didn't fail as expected\n" , buf); |
329 | abort(); |
330 | } |
331 | } |
332 | |
333 | static void mfd_assert_read(int fd) |
334 | { |
335 | char buf[16]; |
336 | void *p; |
337 | ssize_t l; |
338 | |
339 | l = read(fd, buf, sizeof(buf)); |
340 | if (l != sizeof(buf)) { |
341 | printf("read() failed: %m\n" ); |
342 | abort(); |
343 | } |
344 | |
345 | /* verify PROT_READ *is* allowed */ |
346 | p = mmap(NULL, |
347 | mfd_def_size, |
348 | PROT_READ, |
349 | MAP_PRIVATE, |
350 | fd, |
351 | 0); |
352 | if (p == MAP_FAILED) { |
353 | printf("mmap() failed: %m\n" ); |
354 | abort(); |
355 | } |
356 | munmap(p, mfd_def_size); |
357 | |
358 | /* verify MAP_PRIVATE is *always* allowed (even writable) */ |
359 | p = mmap(NULL, |
360 | mfd_def_size, |
361 | PROT_READ | PROT_WRITE, |
362 | MAP_PRIVATE, |
363 | fd, |
364 | 0); |
365 | if (p == MAP_FAILED) { |
366 | printf("mmap() failed: %m\n" ); |
367 | abort(); |
368 | } |
369 | munmap(p, mfd_def_size); |
370 | } |
371 | |
372 | /* Test that PROT_READ + MAP_SHARED mappings work. */ |
373 | static void mfd_assert_read_shared(int fd) |
374 | { |
375 | void *p; |
376 | |
377 | /* verify PROT_READ and MAP_SHARED *is* allowed */ |
378 | p = mmap(NULL, |
379 | mfd_def_size, |
380 | PROT_READ, |
381 | MAP_SHARED, |
382 | fd, |
383 | 0); |
384 | if (p == MAP_FAILED) { |
385 | printf("mmap() failed: %m\n" ); |
386 | abort(); |
387 | } |
388 | munmap(p, mfd_def_size); |
389 | } |
390 | |
391 | static void mfd_assert_fork_private_write(int fd) |
392 | { |
393 | int *p; |
394 | pid_t pid; |
395 | |
396 | p = mmap(NULL, |
397 | mfd_def_size, |
398 | PROT_READ | PROT_WRITE, |
399 | MAP_PRIVATE, |
400 | fd, |
401 | 0); |
402 | if (p == MAP_FAILED) { |
403 | printf("mmap() failed: %m\n" ); |
404 | abort(); |
405 | } |
406 | |
407 | p[0] = 22; |
408 | |
409 | pid = fork(); |
410 | if (pid == 0) { |
411 | p[0] = 33; |
412 | exit(0); |
413 | } else { |
414 | waitpid(pid, NULL, 0); |
415 | |
416 | if (p[0] != 22) { |
417 | printf("MAP_PRIVATE copy-on-write failed: %m\n" ); |
418 | abort(); |
419 | } |
420 | } |
421 | |
422 | munmap(p, mfd_def_size); |
423 | } |
424 | |
425 | static void mfd_assert_write(int fd) |
426 | { |
427 | ssize_t l; |
428 | void *p; |
429 | int r; |
430 | |
431 | /* |
432 | * huegtlbfs does not support write, but we want to |
433 | * verify everything else here. |
434 | */ |
435 | if (!hugetlbfs_test) { |
436 | /* verify write() succeeds */ |
437 | l = write(fd, "\0\0\0\0" , 4); |
438 | if (l != 4) { |
439 | printf("write() failed: %m\n" ); |
440 | abort(); |
441 | } |
442 | } |
443 | |
444 | /* verify PROT_READ | PROT_WRITE is allowed */ |
445 | p = mmap(NULL, |
446 | mfd_def_size, |
447 | PROT_READ | PROT_WRITE, |
448 | MAP_SHARED, |
449 | fd, |
450 | 0); |
451 | if (p == MAP_FAILED) { |
452 | printf("mmap() failed: %m\n" ); |
453 | abort(); |
454 | } |
455 | *(char *)p = 0; |
456 | munmap(p, mfd_def_size); |
457 | |
458 | /* verify PROT_WRITE is allowed */ |
459 | p = mmap(NULL, |
460 | mfd_def_size, |
461 | PROT_WRITE, |
462 | MAP_SHARED, |
463 | fd, |
464 | 0); |
465 | if (p == MAP_FAILED) { |
466 | printf("mmap() failed: %m\n" ); |
467 | abort(); |
468 | } |
469 | *(char *)p = 0; |
470 | munmap(p, mfd_def_size); |
471 | |
472 | /* verify PROT_READ with MAP_SHARED is allowed and a following |
473 | * mprotect(PROT_WRITE) allows writing */ |
474 | p = mmap(NULL, |
475 | mfd_def_size, |
476 | PROT_READ, |
477 | MAP_SHARED, |
478 | fd, |
479 | 0); |
480 | if (p == MAP_FAILED) { |
481 | printf("mmap() failed: %m\n" ); |
482 | abort(); |
483 | } |
484 | |
485 | r = mprotect(p, mfd_def_size, PROT_READ | PROT_WRITE); |
486 | if (r < 0) { |
487 | printf("mprotect() failed: %m\n" ); |
488 | abort(); |
489 | } |
490 | |
491 | *(char *)p = 0; |
492 | munmap(p, mfd_def_size); |
493 | |
494 | /* verify PUNCH_HOLE works */ |
495 | r = fallocate(fd, |
496 | FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE, |
497 | 0, |
498 | mfd_def_size); |
499 | if (r < 0) { |
500 | printf("fallocate(PUNCH_HOLE) failed: %m\n" ); |
501 | abort(); |
502 | } |
503 | } |
504 | |
505 | static void mfd_fail_write(int fd) |
506 | { |
507 | ssize_t l; |
508 | void *p; |
509 | int r; |
510 | |
511 | /* verify write() fails */ |
512 | l = write(fd, "data" , 4); |
513 | if (l != -EPERM) { |
514 | printf("expected EPERM on write(), but got %d: %m\n" , (int)l); |
515 | abort(); |
516 | } |
517 | |
518 | /* verify PROT_READ | PROT_WRITE is not allowed */ |
519 | p = mmap(NULL, |
520 | mfd_def_size, |
521 | PROT_READ | PROT_WRITE, |
522 | MAP_SHARED, |
523 | fd, |
524 | 0); |
525 | if (p != MAP_FAILED) { |
526 | printf("mmap() didn't fail as expected\n" ); |
527 | abort(); |
528 | } |
529 | |
530 | /* verify PROT_WRITE is not allowed */ |
531 | p = mmap(NULL, |
532 | mfd_def_size, |
533 | PROT_WRITE, |
534 | MAP_SHARED, |
535 | fd, |
536 | 0); |
537 | if (p != MAP_FAILED) { |
538 | printf("mmap() didn't fail as expected\n" ); |
539 | abort(); |
540 | } |
541 | |
542 | /* Verify PROT_READ with MAP_SHARED with a following mprotect is not |
543 | * allowed. Note that for r/w the kernel already prevents the mmap. */ |
544 | p = mmap(NULL, |
545 | mfd_def_size, |
546 | PROT_READ, |
547 | MAP_SHARED, |
548 | fd, |
549 | 0); |
550 | if (p != MAP_FAILED) { |
551 | r = mprotect(p, mfd_def_size, PROT_READ | PROT_WRITE); |
552 | if (r >= 0) { |
553 | printf("mmap()+mprotect() didn't fail as expected\n" ); |
554 | abort(); |
555 | } |
556 | munmap(p, mfd_def_size); |
557 | } |
558 | |
559 | /* verify PUNCH_HOLE fails */ |
560 | r = fallocate(fd, |
561 | FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE, |
562 | 0, |
563 | mfd_def_size); |
564 | if (r >= 0) { |
565 | printf("fallocate(PUNCH_HOLE) didn't fail as expected\n" ); |
566 | abort(); |
567 | } |
568 | } |
569 | |
570 | static void mfd_assert_shrink(int fd) |
571 | { |
572 | int r, fd2; |
573 | |
574 | r = ftruncate(fd, mfd_def_size / 2); |
575 | if (r < 0) { |
576 | printf("ftruncate(SHRINK) failed: %m\n" ); |
577 | abort(); |
578 | } |
579 | |
580 | mfd_assert_size(fd, size: mfd_def_size / 2); |
581 | |
582 | fd2 = mfd_assert_open(fd, |
583 | O_RDWR | O_CREAT | O_TRUNC, |
584 | S_IRUSR | S_IWUSR); |
585 | close(fd2); |
586 | |
587 | mfd_assert_size(fd, size: 0); |
588 | } |
589 | |
590 | static void mfd_fail_shrink(int fd) |
591 | { |
592 | int r; |
593 | |
594 | r = ftruncate(fd, mfd_def_size / 2); |
595 | if (r >= 0) { |
596 | printf("ftruncate(SHRINK) didn't fail as expected\n" ); |
597 | abort(); |
598 | } |
599 | |
600 | mfd_fail_open(fd, |
601 | O_RDWR | O_CREAT | O_TRUNC, |
602 | S_IRUSR | S_IWUSR); |
603 | } |
604 | |
605 | static void mfd_assert_grow(int fd) |
606 | { |
607 | int r; |
608 | |
609 | r = ftruncate(fd, mfd_def_size * 2); |
610 | if (r < 0) { |
611 | printf("ftruncate(GROW) failed: %m\n" ); |
612 | abort(); |
613 | } |
614 | |
615 | mfd_assert_size(fd, size: mfd_def_size * 2); |
616 | |
617 | r = fallocate(fd, |
618 | 0, |
619 | 0, |
620 | mfd_def_size * 4); |
621 | if (r < 0) { |
622 | printf("fallocate(ALLOC) failed: %m\n" ); |
623 | abort(); |
624 | } |
625 | |
626 | mfd_assert_size(fd, size: mfd_def_size * 4); |
627 | } |
628 | |
629 | static void mfd_fail_grow(int fd) |
630 | { |
631 | int r; |
632 | |
633 | r = ftruncate(fd, mfd_def_size * 2); |
634 | if (r >= 0) { |
635 | printf("ftruncate(GROW) didn't fail as expected\n" ); |
636 | abort(); |
637 | } |
638 | |
639 | r = fallocate(fd, |
640 | 0, |
641 | 0, |
642 | mfd_def_size * 4); |
643 | if (r >= 0) { |
644 | printf("fallocate(ALLOC) didn't fail as expected\n" ); |
645 | abort(); |
646 | } |
647 | } |
648 | |
649 | static void mfd_assert_grow_write(int fd) |
650 | { |
651 | static char *buf; |
652 | ssize_t l; |
653 | |
654 | /* hugetlbfs does not support write */ |
655 | if (hugetlbfs_test) |
656 | return; |
657 | |
658 | buf = malloc(mfd_def_size * 8); |
659 | if (!buf) { |
660 | printf("malloc(%zu) failed: %m\n" , mfd_def_size * 8); |
661 | abort(); |
662 | } |
663 | |
664 | l = pwrite(fd, buf, mfd_def_size * 8, 0); |
665 | if (l != (mfd_def_size * 8)) { |
666 | printf("pwrite() failed: %m\n" ); |
667 | abort(); |
668 | } |
669 | |
670 | mfd_assert_size(fd, size: mfd_def_size * 8); |
671 | } |
672 | |
673 | static void mfd_fail_grow_write(int fd) |
674 | { |
675 | static char *buf; |
676 | ssize_t l; |
677 | |
678 | /* hugetlbfs does not support write */ |
679 | if (hugetlbfs_test) |
680 | return; |
681 | |
682 | buf = malloc(mfd_def_size * 8); |
683 | if (!buf) { |
684 | printf("malloc(%zu) failed: %m\n" , mfd_def_size * 8); |
685 | abort(); |
686 | } |
687 | |
688 | l = pwrite(fd, buf, mfd_def_size * 8, 0); |
689 | if (l == (mfd_def_size * 8)) { |
690 | printf("pwrite() didn't fail as expected\n" ); |
691 | abort(); |
692 | } |
693 | } |
694 | |
695 | static void mfd_assert_mode(int fd, int mode) |
696 | { |
697 | struct stat st; |
698 | char buf[PATH_MAX]; |
699 | int nbytes; |
700 | |
701 | fd2name(fd, buf, PATH_MAX); |
702 | |
703 | if (fstat(fd, &st) < 0) { |
704 | printf("fstat(%s) failed: %m\n" , buf); |
705 | abort(); |
706 | } |
707 | |
708 | if ((st.st_mode & 07777) != mode) { |
709 | printf("fstat(%s) wrong file mode 0%04o, but expected 0%04o\n" , |
710 | buf, (int)st.st_mode & 07777, mode); |
711 | abort(); |
712 | } |
713 | } |
714 | |
715 | static void mfd_assert_chmod(int fd, int mode) |
716 | { |
717 | char buf[PATH_MAX]; |
718 | int nbytes; |
719 | |
720 | fd2name(fd, buf, PATH_MAX); |
721 | |
722 | if (fchmod(fd, mode) < 0) { |
723 | printf("fchmod(%s, 0%04o) failed: %m\n" , buf, mode); |
724 | abort(); |
725 | } |
726 | |
727 | mfd_assert_mode(fd, mode); |
728 | } |
729 | |
730 | static void mfd_fail_chmod(int fd, int mode) |
731 | { |
732 | struct stat st; |
733 | char buf[PATH_MAX]; |
734 | int nbytes; |
735 | |
736 | fd2name(fd, buf, PATH_MAX); |
737 | |
738 | if (fstat(fd, &st) < 0) { |
739 | printf("fstat(%s) failed: %m\n" , buf); |
740 | abort(); |
741 | } |
742 | |
743 | if (fchmod(fd, mode) == 0) { |
744 | printf("fchmod(%s, 0%04o) didn't fail as expected\n" , |
745 | buf, mode); |
746 | abort(); |
747 | } |
748 | |
749 | /* verify that file mode bits did not change */ |
750 | mfd_assert_mode(fd, mode: st.st_mode & 07777); |
751 | } |
752 | |
753 | static int idle_thread_fn(void *arg) |
754 | { |
755 | sigset_t set; |
756 | int sig; |
757 | |
758 | /* dummy waiter; SIGTERM terminates us anyway */ |
759 | sigemptyset(&set); |
760 | sigaddset(&set, SIGTERM); |
761 | sigwait(&set, &sig); |
762 | |
763 | return 0; |
764 | } |
765 | |
766 | static pid_t spawn_thread(unsigned int flags, int (*fn)(void *), void *arg) |
767 | { |
768 | uint8_t *stack; |
769 | pid_t pid; |
770 | |
771 | stack = malloc(STACK_SIZE); |
772 | if (!stack) { |
773 | printf("malloc(STACK_SIZE) failed: %m\n" ); |
774 | abort(); |
775 | } |
776 | |
777 | pid = clone(fn, stack + STACK_SIZE, SIGCHLD | flags, arg); |
778 | if (pid < 0) { |
779 | printf("clone() failed: %m\n" ); |
780 | abort(); |
781 | } |
782 | |
783 | return pid; |
784 | } |
785 | |
786 | static void join_thread(pid_t pid) |
787 | { |
788 | int wstatus; |
789 | |
790 | if (waitpid(pid, &wstatus, 0) < 0) { |
791 | printf("newpid thread: waitpid() failed: %m\n" ); |
792 | abort(); |
793 | } |
794 | |
795 | if (WIFEXITED(wstatus) && WEXITSTATUS(wstatus) != 0) { |
796 | printf("newpid thread: exited with non-zero error code %d\n" , |
797 | WEXITSTATUS(wstatus)); |
798 | abort(); |
799 | } |
800 | |
801 | if (WIFSIGNALED(wstatus)) { |
802 | printf("newpid thread: killed by signal %d\n" , |
803 | WTERMSIG(wstatus)); |
804 | abort(); |
805 | } |
806 | } |
807 | |
808 | static pid_t spawn_idle_thread(unsigned int flags) |
809 | { |
810 | return spawn_thread(flags, fn: idle_thread_fn, NULL); |
811 | } |
812 | |
813 | static void join_idle_thread(pid_t pid) |
814 | { |
815 | kill(pid, SIGTERM); |
816 | waitpid(pid, NULL, 0); |
817 | } |
818 | |
819 | /* |
820 | * Test memfd_create() syscall |
821 | * Verify syscall-argument validation, including name checks, flag validation |
822 | * and more. |
823 | */ |
824 | static void test_create(void) |
825 | { |
826 | char buf[2048]; |
827 | int fd; |
828 | |
829 | printf("%s CREATE\n" , memfd_str); |
830 | |
831 | /* test NULL name */ |
832 | mfd_fail_new(NULL, flags: 0); |
833 | |
834 | /* test over-long name (not zero-terminated) */ |
835 | memset(buf, 0xff, sizeof(buf)); |
836 | mfd_fail_new(name: buf, flags: 0); |
837 | |
838 | /* test over-long zero-terminated name */ |
839 | memset(buf, 0xff, sizeof(buf)); |
840 | buf[sizeof(buf) - 1] = 0; |
841 | mfd_fail_new(name: buf, flags: 0); |
842 | |
843 | /* verify "" is a valid name */ |
844 | fd = mfd_assert_new(name: "" , sz: 0, flags: 0); |
845 | close(fd); |
846 | |
847 | /* verify invalid O_* open flags */ |
848 | mfd_fail_new(name: "" , flags: 0x0100); |
849 | mfd_fail_new("" , ~MFD_CLOEXEC); |
850 | mfd_fail_new("" , ~MFD_ALLOW_SEALING); |
851 | mfd_fail_new(name: "" , flags: ~0); |
852 | mfd_fail_new(name: "" , flags: 0x80000000U); |
853 | |
854 | /* verify EXEC and NOEXEC_SEAL can't both be set */ |
855 | mfd_fail_new("" , MFD_EXEC | MFD_NOEXEC_SEAL); |
856 | |
857 | /* verify MFD_CLOEXEC is allowed */ |
858 | fd = mfd_assert_new("" , 0, MFD_CLOEXEC); |
859 | close(fd); |
860 | |
861 | /* verify MFD_ALLOW_SEALING is allowed */ |
862 | fd = mfd_assert_new("" , 0, MFD_ALLOW_SEALING); |
863 | close(fd); |
864 | |
865 | /* verify MFD_ALLOW_SEALING | MFD_CLOEXEC is allowed */ |
866 | fd = mfd_assert_new("" , 0, MFD_ALLOW_SEALING | MFD_CLOEXEC); |
867 | close(fd); |
868 | } |
869 | |
870 | /* |
871 | * Test basic sealing |
872 | * A very basic sealing test to see whether setting/retrieving seals works. |
873 | */ |
874 | static void test_basic(void) |
875 | { |
876 | int fd; |
877 | |
878 | printf("%s BASIC\n" , memfd_str); |
879 | |
880 | fd = mfd_assert_new("kern_memfd_basic" , |
881 | mfd_def_size, |
882 | MFD_CLOEXEC | MFD_ALLOW_SEALING); |
883 | |
884 | /* add basic seals */ |
885 | mfd_assert_has_seals(fd, seals: 0); |
886 | mfd_assert_add_seals(fd, F_SEAL_SHRINK | |
887 | F_SEAL_WRITE); |
888 | mfd_assert_has_seals(fd, F_SEAL_SHRINK | |
889 | F_SEAL_WRITE); |
890 | |
891 | /* add them again */ |
892 | mfd_assert_add_seals(fd, F_SEAL_SHRINK | |
893 | F_SEAL_WRITE); |
894 | mfd_assert_has_seals(fd, F_SEAL_SHRINK | |
895 | F_SEAL_WRITE); |
896 | |
897 | /* add more seals and seal against sealing */ |
898 | mfd_assert_add_seals(fd, F_SEAL_GROW | F_SEAL_SEAL); |
899 | mfd_assert_has_seals(fd, F_SEAL_SHRINK | |
900 | F_SEAL_GROW | |
901 | F_SEAL_WRITE | |
902 | F_SEAL_SEAL); |
903 | |
904 | /* verify that sealing no longer works */ |
905 | mfd_fail_add_seals(fd, F_SEAL_GROW); |
906 | mfd_fail_add_seals(fd, seals: 0); |
907 | |
908 | close(fd); |
909 | |
910 | /* verify sealing does not work without MFD_ALLOW_SEALING */ |
911 | fd = mfd_assert_new("kern_memfd_basic" , |
912 | mfd_def_size, |
913 | MFD_CLOEXEC); |
914 | mfd_assert_has_seals(fd, F_SEAL_SEAL); |
915 | mfd_fail_add_seals(fd, F_SEAL_SHRINK | |
916 | F_SEAL_GROW | |
917 | F_SEAL_WRITE); |
918 | mfd_assert_has_seals(fd, F_SEAL_SEAL); |
919 | close(fd); |
920 | } |
921 | |
922 | /* |
923 | * Test SEAL_WRITE |
924 | * Test whether SEAL_WRITE actually prevents modifications. |
925 | */ |
926 | static void test_seal_write(void) |
927 | { |
928 | int fd; |
929 | |
930 | printf("%s SEAL-WRITE\n" , memfd_str); |
931 | |
932 | fd = mfd_assert_new("kern_memfd_seal_write" , |
933 | mfd_def_size, |
934 | MFD_CLOEXEC | MFD_ALLOW_SEALING); |
935 | mfd_assert_has_seals(fd, seals: 0); |
936 | mfd_assert_add_seals(fd, F_SEAL_WRITE); |
937 | mfd_assert_has_seals(fd, F_SEAL_WRITE); |
938 | |
939 | mfd_assert_read(fd); |
940 | mfd_fail_write(fd); |
941 | mfd_assert_shrink(fd); |
942 | mfd_assert_grow(fd); |
943 | mfd_fail_grow_write(fd); |
944 | |
945 | close(fd); |
946 | } |
947 | |
948 | /* |
949 | * Test SEAL_FUTURE_WRITE |
950 | * Test whether SEAL_FUTURE_WRITE actually prevents modifications. |
951 | */ |
952 | static void test_seal_future_write(void) |
953 | { |
954 | int fd, fd2; |
955 | void *p; |
956 | |
957 | printf("%s SEAL-FUTURE-WRITE\n" , memfd_str); |
958 | |
959 | fd = mfd_assert_new("kern_memfd_seal_future_write" , |
960 | mfd_def_size, |
961 | MFD_CLOEXEC | MFD_ALLOW_SEALING); |
962 | |
963 | p = mfd_assert_mmap_shared(fd); |
964 | |
965 | mfd_assert_has_seals(fd, seals: 0); |
966 | |
967 | mfd_assert_add_seals(fd, F_SEAL_FUTURE_WRITE); |
968 | mfd_assert_has_seals(fd, F_SEAL_FUTURE_WRITE); |
969 | |
970 | /* read should pass, writes should fail */ |
971 | mfd_assert_read(fd); |
972 | mfd_assert_read_shared(fd); |
973 | mfd_fail_write(fd); |
974 | |
975 | fd2 = mfd_assert_reopen_fd(fd_in: fd); |
976 | /* read should pass, writes should still fail */ |
977 | mfd_assert_read(fd: fd2); |
978 | mfd_assert_read_shared(fd: fd2); |
979 | mfd_fail_write(fd: fd2); |
980 | |
981 | mfd_assert_fork_private_write(fd); |
982 | |
983 | munmap(p, mfd_def_size); |
984 | close(fd2); |
985 | close(fd); |
986 | } |
987 | |
988 | /* |
989 | * Test SEAL_SHRINK |
990 | * Test whether SEAL_SHRINK actually prevents shrinking |
991 | */ |
992 | static void test_seal_shrink(void) |
993 | { |
994 | int fd; |
995 | |
996 | printf("%s SEAL-SHRINK\n" , memfd_str); |
997 | |
998 | fd = mfd_assert_new("kern_memfd_seal_shrink" , |
999 | mfd_def_size, |
1000 | MFD_CLOEXEC | MFD_ALLOW_SEALING); |
1001 | mfd_assert_has_seals(fd, seals: 0); |
1002 | mfd_assert_add_seals(fd, F_SEAL_SHRINK); |
1003 | mfd_assert_has_seals(fd, F_SEAL_SHRINK); |
1004 | |
1005 | mfd_assert_read(fd); |
1006 | mfd_assert_write(fd); |
1007 | mfd_fail_shrink(fd); |
1008 | mfd_assert_grow(fd); |
1009 | mfd_assert_grow_write(fd); |
1010 | |
1011 | close(fd); |
1012 | } |
1013 | |
1014 | /* |
1015 | * Test SEAL_GROW |
1016 | * Test whether SEAL_GROW actually prevents growing |
1017 | */ |
1018 | static void test_seal_grow(void) |
1019 | { |
1020 | int fd; |
1021 | |
1022 | printf("%s SEAL-GROW\n" , memfd_str); |
1023 | |
1024 | fd = mfd_assert_new("kern_memfd_seal_grow" , |
1025 | mfd_def_size, |
1026 | MFD_CLOEXEC | MFD_ALLOW_SEALING); |
1027 | mfd_assert_has_seals(fd, seals: 0); |
1028 | mfd_assert_add_seals(fd, F_SEAL_GROW); |
1029 | mfd_assert_has_seals(fd, F_SEAL_GROW); |
1030 | |
1031 | mfd_assert_read(fd); |
1032 | mfd_assert_write(fd); |
1033 | mfd_assert_shrink(fd); |
1034 | mfd_fail_grow(fd); |
1035 | mfd_fail_grow_write(fd); |
1036 | |
1037 | close(fd); |
1038 | } |
1039 | |
1040 | /* |
1041 | * Test SEAL_SHRINK | SEAL_GROW |
1042 | * Test whether SEAL_SHRINK | SEAL_GROW actually prevents resizing |
1043 | */ |
1044 | static void test_seal_resize(void) |
1045 | { |
1046 | int fd; |
1047 | |
1048 | printf("%s SEAL-RESIZE\n" , memfd_str); |
1049 | |
1050 | fd = mfd_assert_new("kern_memfd_seal_resize" , |
1051 | mfd_def_size, |
1052 | MFD_CLOEXEC | MFD_ALLOW_SEALING); |
1053 | mfd_assert_has_seals(fd, seals: 0); |
1054 | mfd_assert_add_seals(fd, F_SEAL_SHRINK | F_SEAL_GROW); |
1055 | mfd_assert_has_seals(fd, F_SEAL_SHRINK | F_SEAL_GROW); |
1056 | |
1057 | mfd_assert_read(fd); |
1058 | mfd_assert_write(fd); |
1059 | mfd_fail_shrink(fd); |
1060 | mfd_fail_grow(fd); |
1061 | mfd_fail_grow_write(fd); |
1062 | |
1063 | close(fd); |
1064 | } |
1065 | |
1066 | /* |
1067 | * Test SEAL_EXEC |
1068 | * Test fd is created with exec and allow sealing. |
1069 | * chmod() cannot change x bits after sealing. |
1070 | */ |
1071 | static void test_exec_seal(void) |
1072 | { |
1073 | int fd; |
1074 | |
1075 | printf("%s SEAL-EXEC\n" , memfd_str); |
1076 | |
1077 | printf("%s Apply SEAL_EXEC\n" , memfd_str); |
1078 | fd = mfd_assert_new("kern_memfd_seal_exec" , |
1079 | mfd_def_size, |
1080 | MFD_CLOEXEC | MFD_ALLOW_SEALING | MFD_EXEC); |
1081 | |
1082 | mfd_assert_mode(fd, mode: 0777); |
1083 | mfd_assert_chmod(fd, mode: 0644); |
1084 | |
1085 | mfd_assert_has_seals(fd, seals: 0); |
1086 | mfd_assert_add_seals(fd, F_SEAL_EXEC); |
1087 | mfd_assert_has_seals(fd, F_SEAL_EXEC); |
1088 | |
1089 | mfd_assert_chmod(fd, mode: 0600); |
1090 | mfd_fail_chmod(fd, mode: 0777); |
1091 | mfd_fail_chmod(fd, mode: 0670); |
1092 | mfd_fail_chmod(fd, mode: 0605); |
1093 | mfd_fail_chmod(fd, mode: 0700); |
1094 | mfd_fail_chmod(fd, mode: 0100); |
1095 | mfd_assert_chmod(fd, mode: 0666); |
1096 | mfd_assert_write(fd); |
1097 | close(fd); |
1098 | |
1099 | printf("%s Apply ALL_SEALS\n" , memfd_str); |
1100 | fd = mfd_assert_new("kern_memfd_seal_exec" , |
1101 | mfd_def_size, |
1102 | MFD_CLOEXEC | MFD_ALLOW_SEALING | MFD_EXEC); |
1103 | |
1104 | mfd_assert_mode(fd, mode: 0777); |
1105 | mfd_assert_chmod(fd, mode: 0700); |
1106 | |
1107 | mfd_assert_has_seals(fd, seals: 0); |
1108 | mfd_assert_add_seals(fd, F_SEAL_EXEC); |
1109 | mfd_assert_has_seals(fd, F_WX_SEALS); |
1110 | |
1111 | mfd_fail_chmod(fd, mode: 0711); |
1112 | mfd_fail_chmod(fd, mode: 0600); |
1113 | mfd_fail_write(fd); |
1114 | close(fd); |
1115 | } |
1116 | |
1117 | /* |
1118 | * Test EXEC_NO_SEAL |
1119 | * Test fd is created with exec and not allow sealing. |
1120 | */ |
1121 | static void test_exec_no_seal(void) |
1122 | { |
1123 | int fd; |
1124 | |
1125 | printf("%s EXEC_NO_SEAL\n" , memfd_str); |
1126 | |
1127 | /* Create with EXEC but without ALLOW_SEALING */ |
1128 | fd = mfd_assert_new("kern_memfd_exec_no_sealing" , |
1129 | mfd_def_size, |
1130 | MFD_CLOEXEC | MFD_EXEC); |
1131 | mfd_assert_mode(fd, mode: 0777); |
1132 | mfd_assert_has_seals(fd, F_SEAL_SEAL); |
1133 | mfd_assert_chmod(fd, mode: 0666); |
1134 | close(fd); |
1135 | } |
1136 | |
1137 | /* |
1138 | * Test memfd_create with MFD_NOEXEC flag |
1139 | */ |
1140 | static void test_noexec_seal(void) |
1141 | { |
1142 | int fd; |
1143 | |
1144 | printf("%s NOEXEC_SEAL\n" , memfd_str); |
1145 | |
1146 | /* Create with NOEXEC and ALLOW_SEALING */ |
1147 | fd = mfd_assert_new("kern_memfd_noexec" , |
1148 | mfd_def_size, |
1149 | MFD_CLOEXEC | MFD_ALLOW_SEALING | MFD_NOEXEC_SEAL); |
1150 | mfd_assert_mode(fd, mode: 0666); |
1151 | mfd_assert_has_seals(fd, F_SEAL_EXEC); |
1152 | mfd_fail_chmod(fd, mode: 0777); |
1153 | close(fd); |
1154 | |
1155 | /* Create with NOEXEC but without ALLOW_SEALING */ |
1156 | fd = mfd_assert_new("kern_memfd_noexec" , |
1157 | mfd_def_size, |
1158 | MFD_CLOEXEC | MFD_NOEXEC_SEAL); |
1159 | mfd_assert_mode(fd, mode: 0666); |
1160 | mfd_assert_has_seals(fd, F_SEAL_EXEC); |
1161 | mfd_fail_chmod(fd, mode: 0777); |
1162 | close(fd); |
1163 | } |
1164 | |
1165 | static void test_sysctl_sysctl0(void) |
1166 | { |
1167 | int fd; |
1168 | |
1169 | sysctl_assert_equal(val: "0" ); |
1170 | |
1171 | fd = mfd_assert_new("kern_memfd_sysctl_0_dfl" , |
1172 | mfd_def_size, |
1173 | MFD_CLOEXEC | MFD_ALLOW_SEALING); |
1174 | mfd_assert_mode(fd, mode: 0777); |
1175 | mfd_assert_has_seals(fd, seals: 0); |
1176 | mfd_assert_chmod(fd, mode: 0644); |
1177 | close(fd); |
1178 | } |
1179 | |
1180 | static void test_sysctl_set_sysctl0(void) |
1181 | { |
1182 | sysctl_assert_write(val: "0" ); |
1183 | test_sysctl_sysctl0(); |
1184 | } |
1185 | |
1186 | static void test_sysctl_sysctl1(void) |
1187 | { |
1188 | int fd; |
1189 | |
1190 | sysctl_assert_equal(val: "1" ); |
1191 | |
1192 | fd = mfd_assert_new("kern_memfd_sysctl_1_dfl" , |
1193 | mfd_def_size, |
1194 | MFD_CLOEXEC | MFD_ALLOW_SEALING); |
1195 | mfd_assert_mode(fd, mode: 0666); |
1196 | mfd_assert_has_seals(fd, F_SEAL_EXEC); |
1197 | mfd_fail_chmod(fd, mode: 0777); |
1198 | close(fd); |
1199 | |
1200 | fd = mfd_assert_new("kern_memfd_sysctl_1_exec" , |
1201 | mfd_def_size, |
1202 | MFD_CLOEXEC | MFD_EXEC | MFD_ALLOW_SEALING); |
1203 | mfd_assert_mode(fd, mode: 0777); |
1204 | mfd_assert_has_seals(fd, seals: 0); |
1205 | mfd_assert_chmod(fd, mode: 0644); |
1206 | close(fd); |
1207 | |
1208 | fd = mfd_assert_new("kern_memfd_sysctl_1_noexec" , |
1209 | mfd_def_size, |
1210 | MFD_CLOEXEC | MFD_NOEXEC_SEAL | MFD_ALLOW_SEALING); |
1211 | mfd_assert_mode(fd, mode: 0666); |
1212 | mfd_assert_has_seals(fd, F_SEAL_EXEC); |
1213 | mfd_fail_chmod(fd, mode: 0777); |
1214 | close(fd); |
1215 | } |
1216 | |
1217 | static void test_sysctl_set_sysctl1(void) |
1218 | { |
1219 | sysctl_assert_write(val: "1" ); |
1220 | test_sysctl_sysctl1(); |
1221 | } |
1222 | |
1223 | static void test_sysctl_sysctl2(void) |
1224 | { |
1225 | int fd; |
1226 | |
1227 | sysctl_assert_equal(val: "2" ); |
1228 | |
1229 | fd = mfd_assert_new("kern_memfd_sysctl_2_dfl" , |
1230 | mfd_def_size, |
1231 | MFD_CLOEXEC | MFD_ALLOW_SEALING); |
1232 | mfd_assert_mode(fd, mode: 0666); |
1233 | mfd_assert_has_seals(fd, F_SEAL_EXEC); |
1234 | mfd_fail_chmod(fd, mode: 0777); |
1235 | close(fd); |
1236 | |
1237 | mfd_fail_new("kern_memfd_sysctl_2_exec" , |
1238 | MFD_CLOEXEC | MFD_EXEC | MFD_ALLOW_SEALING); |
1239 | |
1240 | fd = mfd_assert_new("kern_memfd_sysctl_2_noexec" , |
1241 | mfd_def_size, |
1242 | MFD_CLOEXEC | MFD_NOEXEC_SEAL | MFD_ALLOW_SEALING); |
1243 | mfd_assert_mode(fd, mode: 0666); |
1244 | mfd_assert_has_seals(fd, F_SEAL_EXEC); |
1245 | mfd_fail_chmod(fd, mode: 0777); |
1246 | close(fd); |
1247 | } |
1248 | |
1249 | static void test_sysctl_set_sysctl2(void) |
1250 | { |
1251 | sysctl_assert_write(val: "2" ); |
1252 | test_sysctl_sysctl2(); |
1253 | } |
1254 | |
1255 | static int sysctl_simple_child(void *arg) |
1256 | { |
1257 | int fd; |
1258 | int pid; |
1259 | |
1260 | printf("%s sysctl 0\n" , memfd_str); |
1261 | test_sysctl_set_sysctl0(); |
1262 | |
1263 | printf("%s sysctl 1\n" , memfd_str); |
1264 | test_sysctl_set_sysctl1(); |
1265 | |
1266 | printf("%s sysctl 0\n" , memfd_str); |
1267 | test_sysctl_set_sysctl0(); |
1268 | |
1269 | printf("%s sysctl 2\n" , memfd_str); |
1270 | test_sysctl_set_sysctl2(); |
1271 | |
1272 | printf("%s sysctl 1\n" , memfd_str); |
1273 | test_sysctl_set_sysctl1(); |
1274 | |
1275 | printf("%s sysctl 0\n" , memfd_str); |
1276 | test_sysctl_set_sysctl0(); |
1277 | |
1278 | return 0; |
1279 | } |
1280 | |
1281 | /* |
1282 | * Test sysctl |
1283 | * A very basic test to make sure the core sysctl semantics work. |
1284 | */ |
1285 | static void test_sysctl_simple(void) |
1286 | { |
1287 | int pid = spawn_thread(CLONE_NEWPID, sysctl_simple_child, NULL); |
1288 | |
1289 | join_thread(pid); |
1290 | } |
1291 | |
1292 | static int sysctl_nested(void *arg) |
1293 | { |
1294 | void (*fn)(void) = arg; |
1295 | |
1296 | fn(); |
1297 | return 0; |
1298 | } |
1299 | |
1300 | static int sysctl_nested_wait(void *arg) |
1301 | { |
1302 | /* Wait for a SIGCONT. */ |
1303 | kill(getpid(), SIGSTOP); |
1304 | return sysctl_nested(arg); |
1305 | } |
1306 | |
1307 | static void test_sysctl_sysctl1_failset(void) |
1308 | { |
1309 | sysctl_fail_write(val: "0" ); |
1310 | test_sysctl_sysctl1(); |
1311 | } |
1312 | |
1313 | static void test_sysctl_sysctl2_failset(void) |
1314 | { |
1315 | sysctl_fail_write(val: "1" ); |
1316 | test_sysctl_sysctl2(); |
1317 | |
1318 | sysctl_fail_write(val: "0" ); |
1319 | test_sysctl_sysctl2(); |
1320 | } |
1321 | |
1322 | static int sysctl_nested_child(void *arg) |
1323 | { |
1324 | int fd; |
1325 | int pid; |
1326 | |
1327 | printf("%s nested sysctl 0\n" , memfd_str); |
1328 | sysctl_assert_write(val: "0" ); |
1329 | /* A further nested pidns works the same. */ |
1330 | pid = spawn_thread(CLONE_NEWPID, sysctl_simple_child, NULL); |
1331 | join_thread(pid); |
1332 | |
1333 | printf("%s nested sysctl 1\n" , memfd_str); |
1334 | sysctl_assert_write(val: "1" ); |
1335 | /* Child inherits our setting. */ |
1336 | pid = spawn_thread(CLONE_NEWPID, sysctl_nested, test_sysctl_sysctl1); |
1337 | join_thread(pid); |
1338 | /* Child cannot raise the setting. */ |
1339 | pid = spawn_thread(CLONE_NEWPID, sysctl_nested, |
1340 | test_sysctl_sysctl1_failset); |
1341 | join_thread(pid); |
1342 | /* Child can lower the setting. */ |
1343 | pid = spawn_thread(CLONE_NEWPID, sysctl_nested, |
1344 | test_sysctl_set_sysctl2); |
1345 | join_thread(pid); |
1346 | /* Child lowering the setting has no effect on our setting. */ |
1347 | test_sysctl_sysctl1(); |
1348 | |
1349 | printf("%s nested sysctl 2\n" , memfd_str); |
1350 | sysctl_assert_write(val: "2" ); |
1351 | /* Child inherits our setting. */ |
1352 | pid = spawn_thread(CLONE_NEWPID, sysctl_nested, test_sysctl_sysctl2); |
1353 | join_thread(pid); |
1354 | /* Child cannot raise the setting. */ |
1355 | pid = spawn_thread(CLONE_NEWPID, sysctl_nested, |
1356 | test_sysctl_sysctl2_failset); |
1357 | join_thread(pid); |
1358 | |
1359 | /* Verify that the rules are actually inherited after fork. */ |
1360 | printf("%s nested sysctl 0 -> 1 after fork\n" , memfd_str); |
1361 | sysctl_assert_write(val: "0" ); |
1362 | |
1363 | pid = spawn_thread(CLONE_NEWPID, sysctl_nested_wait, |
1364 | test_sysctl_sysctl1_failset); |
1365 | sysctl_assert_write(val: "1" ); |
1366 | kill(pid, SIGCONT); |
1367 | join_thread(pid); |
1368 | |
1369 | printf("%s nested sysctl 0 -> 2 after fork\n" , memfd_str); |
1370 | sysctl_assert_write(val: "0" ); |
1371 | |
1372 | pid = spawn_thread(CLONE_NEWPID, sysctl_nested_wait, |
1373 | test_sysctl_sysctl2_failset); |
1374 | sysctl_assert_write(val: "2" ); |
1375 | kill(pid, SIGCONT); |
1376 | join_thread(pid); |
1377 | |
1378 | /* |
1379 | * Verify that the current effective setting is saved on fork, meaning |
1380 | * that the parent lowering the sysctl doesn't affect already-forked |
1381 | * children. |
1382 | */ |
1383 | printf("%s nested sysctl 2 -> 1 after fork\n" , memfd_str); |
1384 | sysctl_assert_write(val: "2" ); |
1385 | pid = spawn_thread(CLONE_NEWPID, sysctl_nested_wait, |
1386 | test_sysctl_sysctl2); |
1387 | sysctl_assert_write(val: "1" ); |
1388 | kill(pid, SIGCONT); |
1389 | join_thread(pid); |
1390 | |
1391 | printf("%s nested sysctl 2 -> 0 after fork\n" , memfd_str); |
1392 | sysctl_assert_write(val: "2" ); |
1393 | pid = spawn_thread(CLONE_NEWPID, sysctl_nested_wait, |
1394 | test_sysctl_sysctl2); |
1395 | sysctl_assert_write(val: "0" ); |
1396 | kill(pid, SIGCONT); |
1397 | join_thread(pid); |
1398 | |
1399 | printf("%s nested sysctl 1 -> 0 after fork\n" , memfd_str); |
1400 | sysctl_assert_write(val: "1" ); |
1401 | pid = spawn_thread(CLONE_NEWPID, sysctl_nested_wait, |
1402 | test_sysctl_sysctl1); |
1403 | sysctl_assert_write(val: "0" ); |
1404 | kill(pid, SIGCONT); |
1405 | join_thread(pid); |
1406 | |
1407 | return 0; |
1408 | } |
1409 | |
1410 | /* |
1411 | * Test sysctl with nested pid namespaces |
1412 | * Make sure that the sysctl nesting semantics work correctly. |
1413 | */ |
1414 | static void test_sysctl_nested(void) |
1415 | { |
1416 | int pid = spawn_thread(CLONE_NEWPID, sysctl_nested_child, NULL); |
1417 | |
1418 | join_thread(pid); |
1419 | } |
1420 | |
1421 | /* |
1422 | * Test sharing via dup() |
1423 | * Test that seals are shared between dupped FDs and they're all equal. |
1424 | */ |
1425 | static void test_share_dup(char *banner, char *b_suffix) |
1426 | { |
1427 | int fd, fd2; |
1428 | |
1429 | printf("%s %s %s\n" , memfd_str, banner, b_suffix); |
1430 | |
1431 | fd = mfd_assert_new("kern_memfd_share_dup" , |
1432 | mfd_def_size, |
1433 | MFD_CLOEXEC | MFD_ALLOW_SEALING); |
1434 | mfd_assert_has_seals(fd, seals: 0); |
1435 | |
1436 | fd2 = mfd_assert_dup(fd); |
1437 | mfd_assert_has_seals(fd: fd2, seals: 0); |
1438 | |
1439 | mfd_assert_add_seals(fd, F_SEAL_WRITE); |
1440 | mfd_assert_has_seals(fd, F_SEAL_WRITE); |
1441 | mfd_assert_has_seals(fd2, F_SEAL_WRITE); |
1442 | |
1443 | mfd_assert_add_seals(fd2, F_SEAL_SHRINK); |
1444 | mfd_assert_has_seals(fd, F_SEAL_WRITE | F_SEAL_SHRINK); |
1445 | mfd_assert_has_seals(fd2, F_SEAL_WRITE | F_SEAL_SHRINK); |
1446 | |
1447 | mfd_assert_add_seals(fd, F_SEAL_SEAL); |
1448 | mfd_assert_has_seals(fd, F_SEAL_WRITE | F_SEAL_SHRINK | F_SEAL_SEAL); |
1449 | mfd_assert_has_seals(fd2, F_SEAL_WRITE | F_SEAL_SHRINK | F_SEAL_SEAL); |
1450 | |
1451 | mfd_fail_add_seals(fd, F_SEAL_GROW); |
1452 | mfd_fail_add_seals(fd2, F_SEAL_GROW); |
1453 | mfd_fail_add_seals(fd, F_SEAL_SEAL); |
1454 | mfd_fail_add_seals(fd2, F_SEAL_SEAL); |
1455 | |
1456 | close(fd2); |
1457 | |
1458 | mfd_fail_add_seals(fd, F_SEAL_GROW); |
1459 | close(fd); |
1460 | } |
1461 | |
1462 | /* |
1463 | * Test sealing with active mmap()s |
1464 | * Modifying seals is only allowed if no other mmap() refs exist. |
1465 | */ |
1466 | static void test_share_mmap(char *banner, char *b_suffix) |
1467 | { |
1468 | int fd; |
1469 | void *p; |
1470 | |
1471 | printf("%s %s %s\n" , memfd_str, banner, b_suffix); |
1472 | |
1473 | fd = mfd_assert_new("kern_memfd_share_mmap" , |
1474 | mfd_def_size, |
1475 | MFD_CLOEXEC | MFD_ALLOW_SEALING); |
1476 | mfd_assert_has_seals(fd, seals: 0); |
1477 | |
1478 | /* shared/writable ref prevents sealing WRITE, but allows others */ |
1479 | p = mfd_assert_mmap_shared(fd); |
1480 | mfd_fail_add_seals(fd, F_SEAL_WRITE); |
1481 | mfd_assert_has_seals(fd, seals: 0); |
1482 | mfd_assert_add_seals(fd, F_SEAL_SHRINK); |
1483 | mfd_assert_has_seals(fd, F_SEAL_SHRINK); |
1484 | munmap(p, mfd_def_size); |
1485 | |
1486 | /* readable ref allows sealing */ |
1487 | p = mfd_assert_mmap_private(fd); |
1488 | mfd_assert_add_seals(fd, F_SEAL_WRITE); |
1489 | mfd_assert_has_seals(fd, F_SEAL_WRITE | F_SEAL_SHRINK); |
1490 | munmap(p, mfd_def_size); |
1491 | |
1492 | close(fd); |
1493 | } |
1494 | |
1495 | /* |
1496 | * Test sealing with open(/proc/self/fd/%d) |
1497 | * Via /proc we can get access to a separate file-context for the same memfd. |
1498 | * This is *not* like dup(), but like a real separate open(). Make sure the |
1499 | * semantics are as expected and we correctly check for RDONLY / WRONLY / RDWR. |
1500 | */ |
1501 | static void test_share_open(char *banner, char *b_suffix) |
1502 | { |
1503 | int fd, fd2; |
1504 | |
1505 | printf("%s %s %s\n" , memfd_str, banner, b_suffix); |
1506 | |
1507 | fd = mfd_assert_new("kern_memfd_share_open" , |
1508 | mfd_def_size, |
1509 | MFD_CLOEXEC | MFD_ALLOW_SEALING); |
1510 | mfd_assert_has_seals(fd, seals: 0); |
1511 | |
1512 | fd2 = mfd_assert_open(fd, O_RDWR, 0); |
1513 | mfd_assert_add_seals(fd, F_SEAL_WRITE); |
1514 | mfd_assert_has_seals(fd, F_SEAL_WRITE); |
1515 | mfd_assert_has_seals(fd2, F_SEAL_WRITE); |
1516 | |
1517 | mfd_assert_add_seals(fd2, F_SEAL_SHRINK); |
1518 | mfd_assert_has_seals(fd, F_SEAL_WRITE | F_SEAL_SHRINK); |
1519 | mfd_assert_has_seals(fd2, F_SEAL_WRITE | F_SEAL_SHRINK); |
1520 | |
1521 | close(fd); |
1522 | fd = mfd_assert_open(fd2, O_RDONLY, 0); |
1523 | |
1524 | mfd_fail_add_seals(fd, F_SEAL_SEAL); |
1525 | mfd_assert_has_seals(fd, F_SEAL_WRITE | F_SEAL_SHRINK); |
1526 | mfd_assert_has_seals(fd2, F_SEAL_WRITE | F_SEAL_SHRINK); |
1527 | |
1528 | close(fd2); |
1529 | fd2 = mfd_assert_open(fd, O_RDWR, 0); |
1530 | |
1531 | mfd_assert_add_seals(fd2, F_SEAL_SEAL); |
1532 | mfd_assert_has_seals(fd, F_SEAL_WRITE | F_SEAL_SHRINK | F_SEAL_SEAL); |
1533 | mfd_assert_has_seals(fd2, F_SEAL_WRITE | F_SEAL_SHRINK | F_SEAL_SEAL); |
1534 | |
1535 | close(fd2); |
1536 | close(fd); |
1537 | } |
1538 | |
1539 | /* |
1540 | * Test sharing via fork() |
1541 | * Test whether seal-modifications work as expected with forked childs. |
1542 | */ |
1543 | static void test_share_fork(char *banner, char *b_suffix) |
1544 | { |
1545 | int fd; |
1546 | pid_t pid; |
1547 | |
1548 | printf("%s %s %s\n" , memfd_str, banner, b_suffix); |
1549 | |
1550 | fd = mfd_assert_new("kern_memfd_share_fork" , |
1551 | mfd_def_size, |
1552 | MFD_CLOEXEC | MFD_ALLOW_SEALING); |
1553 | mfd_assert_has_seals(fd, seals: 0); |
1554 | |
1555 | pid = spawn_idle_thread(flags: 0); |
1556 | mfd_assert_add_seals(fd, F_SEAL_SEAL); |
1557 | mfd_assert_has_seals(fd, F_SEAL_SEAL); |
1558 | |
1559 | mfd_fail_add_seals(fd, F_SEAL_WRITE); |
1560 | mfd_assert_has_seals(fd, F_SEAL_SEAL); |
1561 | |
1562 | join_idle_thread(pid); |
1563 | |
1564 | mfd_fail_add_seals(fd, F_SEAL_WRITE); |
1565 | mfd_assert_has_seals(fd, F_SEAL_SEAL); |
1566 | |
1567 | close(fd); |
1568 | } |
1569 | |
1570 | int main(int argc, char **argv) |
1571 | { |
1572 | pid_t pid; |
1573 | |
1574 | if (argc == 2) { |
1575 | if (!strcmp(argv[1], "hugetlbfs" )) { |
1576 | unsigned long hpage_size = default_huge_page_size(); |
1577 | |
1578 | if (!hpage_size) { |
1579 | printf("Unable to determine huge page size\n" ); |
1580 | abort(); |
1581 | } |
1582 | |
1583 | hugetlbfs_test = 1; |
1584 | memfd_str = MEMFD_HUGE_STR; |
1585 | mfd_def_size = hpage_size * 2; |
1586 | } else { |
1587 | printf("Unknown option: %s\n" , argv[1]); |
1588 | abort(); |
1589 | } |
1590 | } |
1591 | |
1592 | test_create(); |
1593 | test_basic(); |
1594 | test_exec_seal(); |
1595 | test_exec_no_seal(); |
1596 | test_noexec_seal(); |
1597 | |
1598 | test_seal_write(); |
1599 | test_seal_future_write(); |
1600 | test_seal_shrink(); |
1601 | test_seal_grow(); |
1602 | test_seal_resize(); |
1603 | |
1604 | test_sysctl_simple(); |
1605 | test_sysctl_nested(); |
1606 | |
1607 | test_share_dup(banner: "SHARE-DUP" , b_suffix: "" ); |
1608 | test_share_mmap(banner: "SHARE-MMAP" , b_suffix: "" ); |
1609 | test_share_open(banner: "SHARE-OPEN" , b_suffix: "" ); |
1610 | test_share_fork(banner: "SHARE-FORK" , b_suffix: "" ); |
1611 | |
1612 | /* Run test-suite in a multi-threaded environment with a shared |
1613 | * file-table. */ |
1614 | pid = spawn_idle_thread(CLONE_FILES | CLONE_FS | CLONE_VM); |
1615 | test_share_dup(banner: "SHARE-DUP" , SHARED_FT_STR); |
1616 | test_share_mmap(banner: "SHARE-MMAP" , SHARED_FT_STR); |
1617 | test_share_open(banner: "SHARE-OPEN" , SHARED_FT_STR); |
1618 | test_share_fork(banner: "SHARE-FORK" , SHARED_FT_STR); |
1619 | join_idle_thread(pid); |
1620 | |
1621 | printf("memfd: DONE\n" ); |
1622 | |
1623 | return 0; |
1624 | } |
1625 | |