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