]>
git.proxmox.com Git - mirror_ubuntu-artful-kernel.git/blob - tools/testing/selftests/memfd/memfd_test.c
2 #define __EXPORTED_HEADERS__
7 #include <linux/falloc.h>
8 #include <linux/fcntl.h>
9 #include <linux/memfd.h>
17 #include <sys/syscall.h>
20 #define MFD_DEF_SIZE 8192
21 #define STACK_SIZE 65535
23 static int sys_memfd_create(const char *name
,
26 return syscall(__NR_memfd_create
, name
, flags
);
29 static int mfd_assert_new(const char *name
, loff_t sz
, unsigned int flags
)
33 fd
= sys_memfd_create(name
, flags
);
35 printf("memfd_create(\"%s\", %u) failed: %m\n",
40 r
= ftruncate(fd
, sz
);
42 printf("ftruncate(%llu) failed: %m\n", (unsigned long long)sz
);
49 static void mfd_fail_new(const char *name
, unsigned int flags
)
53 r
= sys_memfd_create(name
, flags
);
55 printf("memfd_create(\"%s\", %u) succeeded, but failure expected\n",
62 static unsigned int mfd_assert_get_seals(int fd
)
66 r
= fcntl(fd
, F_GET_SEALS
);
68 printf("GET_SEALS(%d) failed: %m\n", fd
);
72 return (unsigned int)r
;
75 static void mfd_assert_has_seals(int fd
, unsigned int seals
)
79 s
= mfd_assert_get_seals(fd
);
81 printf("%u != %u = GET_SEALS(%d)\n", seals
, s
, fd
);
86 static void mfd_assert_add_seals(int fd
, unsigned int seals
)
91 s
= mfd_assert_get_seals(fd
);
92 r
= fcntl(fd
, F_ADD_SEALS
, seals
);
94 printf("ADD_SEALS(%d, %u -> %u) failed: %m\n", fd
, s
, seals
);
99 static void mfd_fail_add_seals(int fd
, unsigned int seals
)
104 r
= fcntl(fd
, F_GET_SEALS
);
110 r
= fcntl(fd
, F_ADD_SEALS
, seals
);
112 printf("ADD_SEALS(%d, %u -> %u) didn't fail as expected\n",
118 static void mfd_assert_size(int fd
, size_t size
)
125 printf("fstat(%d) failed: %m\n", fd
);
127 } else if (st
.st_size
!= size
) {
128 printf("wrong file size %lld, but expected %lld\n",
129 (long long)st
.st_size
, (long long)size
);
134 static int mfd_assert_dup(int fd
)
140 printf("dup(%d) failed: %m\n", fd
);
147 static void *mfd_assert_mmap_shared(int fd
)
153 PROT_READ
| PROT_WRITE
,
157 if (p
== MAP_FAILED
) {
158 printf("mmap() failed: %m\n");
165 static void *mfd_assert_mmap_private(int fd
)
175 if (p
== MAP_FAILED
) {
176 printf("mmap() failed: %m\n");
183 static int mfd_assert_open(int fd
, int flags
, mode_t mode
)
188 sprintf(buf
, "/proc/self/fd/%d", fd
);
189 r
= open(buf
, flags
, mode
);
191 printf("open(%s) failed: %m\n", buf
);
198 static void mfd_fail_open(int fd
, int flags
, mode_t mode
)
203 sprintf(buf
, "/proc/self/fd/%d", fd
);
204 r
= open(buf
, flags
, mode
);
206 printf("open(%s) didn't fail as expected\n", buf
);
211 static void mfd_assert_read(int fd
)
217 l
= read(fd
, buf
, sizeof(buf
));
218 if (l
!= sizeof(buf
)) {
219 printf("read() failed: %m\n");
223 /* verify PROT_READ *is* allowed */
230 if (p
== MAP_FAILED
) {
231 printf("mmap() failed: %m\n");
234 munmap(p
, MFD_DEF_SIZE
);
236 /* verify MAP_PRIVATE is *always* allowed (even writable) */
239 PROT_READ
| PROT_WRITE
,
243 if (p
== MAP_FAILED
) {
244 printf("mmap() failed: %m\n");
247 munmap(p
, MFD_DEF_SIZE
);
250 static void mfd_assert_write(int fd
)
256 /* verify write() succeeds */
257 l
= write(fd
, "\0\0\0\0", 4);
259 printf("write() failed: %m\n");
263 /* verify PROT_READ | PROT_WRITE is allowed */
266 PROT_READ
| PROT_WRITE
,
270 if (p
== MAP_FAILED
) {
271 printf("mmap() failed: %m\n");
275 munmap(p
, MFD_DEF_SIZE
);
277 /* verify PROT_WRITE is allowed */
284 if (p
== MAP_FAILED
) {
285 printf("mmap() failed: %m\n");
289 munmap(p
, MFD_DEF_SIZE
);
291 /* verify PROT_READ with MAP_SHARED is allowed and a following
292 * mprotect(PROT_WRITE) allows writing */
299 if (p
== MAP_FAILED
) {
300 printf("mmap() failed: %m\n");
304 r
= mprotect(p
, MFD_DEF_SIZE
, PROT_READ
| PROT_WRITE
);
306 printf("mprotect() failed: %m\n");
311 munmap(p
, MFD_DEF_SIZE
);
313 /* verify PUNCH_HOLE works */
315 FALLOC_FL_PUNCH_HOLE
| FALLOC_FL_KEEP_SIZE
,
319 printf("fallocate(PUNCH_HOLE) failed: %m\n");
324 static void mfd_fail_write(int fd
)
330 /* verify write() fails */
331 l
= write(fd
, "data", 4);
333 printf("expected EPERM on write(), but got %d: %m\n", (int)l
);
337 /* verify PROT_READ | PROT_WRITE is not allowed */
340 PROT_READ
| PROT_WRITE
,
344 if (p
!= MAP_FAILED
) {
345 printf("mmap() didn't fail as expected\n");
349 /* verify PROT_WRITE is not allowed */
356 if (p
!= MAP_FAILED
) {
357 printf("mmap() didn't fail as expected\n");
361 /* Verify PROT_READ with MAP_SHARED with a following mprotect is not
362 * allowed. Note that for r/w the kernel already prevents the mmap. */
369 if (p
!= MAP_FAILED
) {
370 r
= mprotect(p
, MFD_DEF_SIZE
, PROT_READ
| PROT_WRITE
);
372 printf("mmap()+mprotect() didn't fail as expected\n");
377 /* verify PUNCH_HOLE fails */
379 FALLOC_FL_PUNCH_HOLE
| FALLOC_FL_KEEP_SIZE
,
383 printf("fallocate(PUNCH_HOLE) didn't fail as expected\n");
388 static void mfd_assert_shrink(int fd
)
392 r
= ftruncate(fd
, MFD_DEF_SIZE
/ 2);
394 printf("ftruncate(SHRINK) failed: %m\n");
398 mfd_assert_size(fd
, MFD_DEF_SIZE
/ 2);
400 fd2
= mfd_assert_open(fd
,
401 O_RDWR
| O_CREAT
| O_TRUNC
,
405 mfd_assert_size(fd
, 0);
408 static void mfd_fail_shrink(int fd
)
412 r
= ftruncate(fd
, MFD_DEF_SIZE
/ 2);
414 printf("ftruncate(SHRINK) didn't fail as expected\n");
419 O_RDWR
| O_CREAT
| O_TRUNC
,
423 static void mfd_assert_grow(int fd
)
427 r
= ftruncate(fd
, MFD_DEF_SIZE
* 2);
429 printf("ftruncate(GROW) failed: %m\n");
433 mfd_assert_size(fd
, MFD_DEF_SIZE
* 2);
440 printf("fallocate(ALLOC) failed: %m\n");
444 mfd_assert_size(fd
, MFD_DEF_SIZE
* 4);
447 static void mfd_fail_grow(int fd
)
451 r
= ftruncate(fd
, MFD_DEF_SIZE
* 2);
453 printf("ftruncate(GROW) didn't fail as expected\n");
462 printf("fallocate(ALLOC) didn't fail as expected\n");
467 static void mfd_assert_grow_write(int fd
)
469 static char buf
[MFD_DEF_SIZE
* 8];
472 l
= pwrite(fd
, buf
, sizeof(buf
), 0);
473 if (l
!= sizeof(buf
)) {
474 printf("pwrite() failed: %m\n");
478 mfd_assert_size(fd
, MFD_DEF_SIZE
* 8);
481 static void mfd_fail_grow_write(int fd
)
483 static char buf
[MFD_DEF_SIZE
* 8];
486 l
= pwrite(fd
, buf
, sizeof(buf
), 0);
487 if (l
== sizeof(buf
)) {
488 printf("pwrite() didn't fail as expected\n");
493 static int idle_thread_fn(void *arg
)
498 /* dummy waiter; SIGTERM terminates us anyway */
500 sigaddset(&set
, SIGTERM
);
506 static pid_t
spawn_idle_thread(unsigned int flags
)
511 stack
= malloc(STACK_SIZE
);
513 printf("malloc(STACK_SIZE) failed: %m\n");
517 pid
= clone(idle_thread_fn
,
522 printf("clone() failed: %m\n");
529 static void join_idle_thread(pid_t pid
)
532 waitpid(pid
, NULL
, 0);
536 * Test memfd_create() syscall
537 * Verify syscall-argument validation, including name checks, flag validation
540 static void test_create(void)
546 mfd_fail_new(NULL
, 0);
548 /* test over-long name (not zero-terminated) */
549 memset(buf
, 0xff, sizeof(buf
));
550 mfd_fail_new(buf
, 0);
552 /* test over-long zero-terminated name */
553 memset(buf
, 0xff, sizeof(buf
));
554 buf
[sizeof(buf
) - 1] = 0;
555 mfd_fail_new(buf
, 0);
557 /* verify "" is a valid name */
558 fd
= mfd_assert_new("", 0, 0);
561 /* verify invalid O_* open flags */
562 mfd_fail_new("", 0x0100);
563 mfd_fail_new("", ~MFD_CLOEXEC
);
564 mfd_fail_new("", ~MFD_ALLOW_SEALING
);
565 mfd_fail_new("", ~0);
566 mfd_fail_new("", 0x80000000U
);
568 /* verify MFD_CLOEXEC is allowed */
569 fd
= mfd_assert_new("", 0, MFD_CLOEXEC
);
572 /* verify MFD_ALLOW_SEALING is allowed */
573 fd
= mfd_assert_new("", 0, MFD_ALLOW_SEALING
);
576 /* verify MFD_ALLOW_SEALING | MFD_CLOEXEC is allowed */
577 fd
= mfd_assert_new("", 0, MFD_ALLOW_SEALING
| MFD_CLOEXEC
);
583 * A very basic sealing test to see whether setting/retrieving seals works.
585 static void test_basic(void)
589 fd
= mfd_assert_new("kern_memfd_basic",
591 MFD_CLOEXEC
| MFD_ALLOW_SEALING
);
593 /* add basic seals */
594 mfd_assert_has_seals(fd
, 0);
595 mfd_assert_add_seals(fd
, F_SEAL_SHRINK
|
597 mfd_assert_has_seals(fd
, F_SEAL_SHRINK
|
601 mfd_assert_add_seals(fd
, F_SEAL_SHRINK
|
603 mfd_assert_has_seals(fd
, F_SEAL_SHRINK
|
606 /* add more seals and seal against sealing */
607 mfd_assert_add_seals(fd
, F_SEAL_GROW
| F_SEAL_SEAL
);
608 mfd_assert_has_seals(fd
, F_SEAL_SHRINK
|
613 /* verify that sealing no longer works */
614 mfd_fail_add_seals(fd
, F_SEAL_GROW
);
615 mfd_fail_add_seals(fd
, 0);
619 /* verify sealing does not work without MFD_ALLOW_SEALING */
620 fd
= mfd_assert_new("kern_memfd_basic",
623 mfd_assert_has_seals(fd
, F_SEAL_SEAL
);
624 mfd_fail_add_seals(fd
, F_SEAL_SHRINK
|
627 mfd_assert_has_seals(fd
, F_SEAL_SEAL
);
633 * Test whether SEAL_WRITE actually prevents modifications.
635 static void test_seal_write(void)
639 fd
= mfd_assert_new("kern_memfd_seal_write",
641 MFD_CLOEXEC
| MFD_ALLOW_SEALING
);
642 mfd_assert_has_seals(fd
, 0);
643 mfd_assert_add_seals(fd
, F_SEAL_WRITE
);
644 mfd_assert_has_seals(fd
, F_SEAL_WRITE
);
648 mfd_assert_shrink(fd
);
650 mfd_fail_grow_write(fd
);
657 * Test whether SEAL_SHRINK actually prevents shrinking
659 static void test_seal_shrink(void)
663 fd
= mfd_assert_new("kern_memfd_seal_shrink",
665 MFD_CLOEXEC
| MFD_ALLOW_SEALING
);
666 mfd_assert_has_seals(fd
, 0);
667 mfd_assert_add_seals(fd
, F_SEAL_SHRINK
);
668 mfd_assert_has_seals(fd
, F_SEAL_SHRINK
);
671 mfd_assert_write(fd
);
674 mfd_assert_grow_write(fd
);
681 * Test whether SEAL_GROW actually prevents growing
683 static void test_seal_grow(void)
687 fd
= mfd_assert_new("kern_memfd_seal_grow",
689 MFD_CLOEXEC
| MFD_ALLOW_SEALING
);
690 mfd_assert_has_seals(fd
, 0);
691 mfd_assert_add_seals(fd
, F_SEAL_GROW
);
692 mfd_assert_has_seals(fd
, F_SEAL_GROW
);
695 mfd_assert_write(fd
);
696 mfd_assert_shrink(fd
);
698 mfd_fail_grow_write(fd
);
704 * Test SEAL_SHRINK | SEAL_GROW
705 * Test whether SEAL_SHRINK | SEAL_GROW actually prevents resizing
707 static void test_seal_resize(void)
711 fd
= mfd_assert_new("kern_memfd_seal_resize",
713 MFD_CLOEXEC
| MFD_ALLOW_SEALING
);
714 mfd_assert_has_seals(fd
, 0);
715 mfd_assert_add_seals(fd
, F_SEAL_SHRINK
| F_SEAL_GROW
);
716 mfd_assert_has_seals(fd
, F_SEAL_SHRINK
| F_SEAL_GROW
);
719 mfd_assert_write(fd
);
722 mfd_fail_grow_write(fd
);
728 * Test sharing via dup()
729 * Test that seals are shared between dupped FDs and they're all equal.
731 static void test_share_dup(void)
735 fd
= mfd_assert_new("kern_memfd_share_dup",
737 MFD_CLOEXEC
| MFD_ALLOW_SEALING
);
738 mfd_assert_has_seals(fd
, 0);
740 fd2
= mfd_assert_dup(fd
);
741 mfd_assert_has_seals(fd2
, 0);
743 mfd_assert_add_seals(fd
, F_SEAL_WRITE
);
744 mfd_assert_has_seals(fd
, F_SEAL_WRITE
);
745 mfd_assert_has_seals(fd2
, F_SEAL_WRITE
);
747 mfd_assert_add_seals(fd2
, F_SEAL_SHRINK
);
748 mfd_assert_has_seals(fd
, F_SEAL_WRITE
| F_SEAL_SHRINK
);
749 mfd_assert_has_seals(fd2
, F_SEAL_WRITE
| F_SEAL_SHRINK
);
751 mfd_assert_add_seals(fd
, F_SEAL_SEAL
);
752 mfd_assert_has_seals(fd
, F_SEAL_WRITE
| F_SEAL_SHRINK
| F_SEAL_SEAL
);
753 mfd_assert_has_seals(fd2
, F_SEAL_WRITE
| F_SEAL_SHRINK
| F_SEAL_SEAL
);
755 mfd_fail_add_seals(fd
, F_SEAL_GROW
);
756 mfd_fail_add_seals(fd2
, F_SEAL_GROW
);
757 mfd_fail_add_seals(fd
, F_SEAL_SEAL
);
758 mfd_fail_add_seals(fd2
, F_SEAL_SEAL
);
762 mfd_fail_add_seals(fd
, F_SEAL_GROW
);
767 * Test sealing with active mmap()s
768 * Modifying seals is only allowed if no other mmap() refs exist.
770 static void test_share_mmap(void)
775 fd
= mfd_assert_new("kern_memfd_share_mmap",
777 MFD_CLOEXEC
| MFD_ALLOW_SEALING
);
778 mfd_assert_has_seals(fd
, 0);
780 /* shared/writable ref prevents sealing WRITE, but allows others */
781 p
= mfd_assert_mmap_shared(fd
);
782 mfd_fail_add_seals(fd
, F_SEAL_WRITE
);
783 mfd_assert_has_seals(fd
, 0);
784 mfd_assert_add_seals(fd
, F_SEAL_SHRINK
);
785 mfd_assert_has_seals(fd
, F_SEAL_SHRINK
);
786 munmap(p
, MFD_DEF_SIZE
);
788 /* readable ref allows sealing */
789 p
= mfd_assert_mmap_private(fd
);
790 mfd_assert_add_seals(fd
, F_SEAL_WRITE
);
791 mfd_assert_has_seals(fd
, F_SEAL_WRITE
| F_SEAL_SHRINK
);
792 munmap(p
, MFD_DEF_SIZE
);
798 * Test sealing with open(/proc/self/fd/%d)
799 * Via /proc we can get access to a separate file-context for the same memfd.
800 * This is *not* like dup(), but like a real separate open(). Make sure the
801 * semantics are as expected and we correctly check for RDONLY / WRONLY / RDWR.
803 static void test_share_open(void)
807 fd
= mfd_assert_new("kern_memfd_share_open",
809 MFD_CLOEXEC
| MFD_ALLOW_SEALING
);
810 mfd_assert_has_seals(fd
, 0);
812 fd2
= mfd_assert_open(fd
, O_RDWR
, 0);
813 mfd_assert_add_seals(fd
, F_SEAL_WRITE
);
814 mfd_assert_has_seals(fd
, F_SEAL_WRITE
);
815 mfd_assert_has_seals(fd2
, F_SEAL_WRITE
);
817 mfd_assert_add_seals(fd2
, F_SEAL_SHRINK
);
818 mfd_assert_has_seals(fd
, F_SEAL_WRITE
| F_SEAL_SHRINK
);
819 mfd_assert_has_seals(fd2
, F_SEAL_WRITE
| F_SEAL_SHRINK
);
822 fd
= mfd_assert_open(fd2
, O_RDONLY
, 0);
824 mfd_fail_add_seals(fd
, F_SEAL_SEAL
);
825 mfd_assert_has_seals(fd
, F_SEAL_WRITE
| F_SEAL_SHRINK
);
826 mfd_assert_has_seals(fd2
, F_SEAL_WRITE
| F_SEAL_SHRINK
);
829 fd2
= mfd_assert_open(fd
, O_RDWR
, 0);
831 mfd_assert_add_seals(fd2
, F_SEAL_SEAL
);
832 mfd_assert_has_seals(fd
, F_SEAL_WRITE
| F_SEAL_SHRINK
| F_SEAL_SEAL
);
833 mfd_assert_has_seals(fd2
, F_SEAL_WRITE
| F_SEAL_SHRINK
| F_SEAL_SEAL
);
840 * Test sharing via fork()
841 * Test whether seal-modifications work as expected with forked childs.
843 static void test_share_fork(void)
848 fd
= mfd_assert_new("kern_memfd_share_fork",
850 MFD_CLOEXEC
| MFD_ALLOW_SEALING
);
851 mfd_assert_has_seals(fd
, 0);
853 pid
= spawn_idle_thread(0);
854 mfd_assert_add_seals(fd
, F_SEAL_SEAL
);
855 mfd_assert_has_seals(fd
, F_SEAL_SEAL
);
857 mfd_fail_add_seals(fd
, F_SEAL_WRITE
);
858 mfd_assert_has_seals(fd
, F_SEAL_SEAL
);
860 join_idle_thread(pid
);
862 mfd_fail_add_seals(fd
, F_SEAL_WRITE
);
863 mfd_assert_has_seals(fd
, F_SEAL_SEAL
);
868 int main(int argc
, char **argv
)
872 printf("memfd: CREATE\n");
874 printf("memfd: BASIC\n");
877 printf("memfd: SEAL-WRITE\n");
879 printf("memfd: SEAL-SHRINK\n");
881 printf("memfd: SEAL-GROW\n");
883 printf("memfd: SEAL-RESIZE\n");
886 printf("memfd: SHARE-DUP\n");
888 printf("memfd: SHARE-MMAP\n");
890 printf("memfd: SHARE-OPEN\n");
892 printf("memfd: SHARE-FORK\n");
895 /* Run test-suite in a multi-threaded environment with a shared
897 pid
= spawn_idle_thread(CLONE_FILES
| CLONE_FS
| CLONE_VM
);
898 printf("memfd: SHARE-DUP (shared file-table)\n");
900 printf("memfd: SHARE-MMAP (shared file-table)\n");
902 printf("memfd: SHARE-OPEN (shared file-table)\n");
904 printf("memfd: SHARE-FORK (shared file-table)\n");
906 join_idle_thread(pid
);
908 printf("memfd: DONE\n");