diff options
Diffstat (limited to 'tools')
| -rw-r--r-- | tools/testing/selftests/mm/merge.c | 88 |
1 files changed, 88 insertions, 0 deletions
diff --git a/tools/testing/selftests/mm/merge.c b/tools/testing/selftests/mm/merge.c index 10b686102b79..519e5ac02db7 100644 --- a/tools/testing/selftests/mm/merge.c +++ b/tools/testing/selftests/mm/merge.c @@ -48,6 +48,19 @@ static pid_t do_fork(struct procmap_fd *procmap) return 0; } +#ifdef __NR_mseal +static int sys_mseal(void *ptr, size_t len, unsigned long flags) +{ + return syscall(__NR_mseal, (unsigned long)ptr, len, flags); +} +#else +static int sys_mseal(void *ptr, size_t len, unsigned long flags) +{ + errno = ENOSYS; + return -1; +} +#endif + FIXTURE_SETUP(merge) { self->page_size = psize(); @@ -1217,6 +1230,81 @@ TEST_F(merge, mremap_correct_placed_faulted) ASSERT_EQ(procmap->query.vma_end, (unsigned long)ptr + 15 * page_size); } +TEST_F(merge, merge_vmas_with_mseal) +{ + unsigned int page_size = self->page_size; + struct procmap_fd *procmap = &self->procmap; + char *ptr, *ptr2, *ptr3; + /* We need our own as cannot munmap() once sealed. */ + char *carveout; + + /* Invalid mseal() call to see if implemented. */ + ASSERT_EQ(sys_mseal(NULL, 0, ~0UL), -1); + if (errno == ENOSYS) + SKIP(return, "mseal not supported, skipping."); + + /* Map carveout. */ + carveout = mmap(NULL, 5 * page_size, PROT_NONE, + MAP_PRIVATE | MAP_ANON, -1, 0); + ASSERT_NE(carveout, MAP_FAILED); + + /* + * Map 3 separate VMAs: + * + * |-----------|-----------|-----------| + * | RW | RWE | RO | + * |-----------|-----------|-----------| + * ptr ptr2 ptr3 + */ + ptr = mmap(&carveout[page_size], page_size, PROT_READ | PROT_WRITE, + MAP_ANON | MAP_PRIVATE | MAP_FIXED, -1, 0); + ASSERT_NE(ptr, MAP_FAILED); + ptr2 = mmap(&carveout[2 * page_size], page_size, + PROT_READ | PROT_WRITE | PROT_EXEC, + MAP_ANON | MAP_PRIVATE | MAP_FIXED, -1, 0); + ASSERT_NE(ptr2, MAP_FAILED); + ptr3 = mmap(&carveout[3 * page_size], page_size, PROT_READ, + MAP_ANON | MAP_PRIVATE | MAP_FIXED, -1, 0); + ASSERT_NE(ptr3, MAP_FAILED); + + /* + * mseal the second VMA: + * + * |-----------|-----------|-----------| + * | RW | RWES | RO | + * |-----------|-----------|-----------| + * ptr ptr2 ptr3 + */ + ASSERT_EQ(sys_mseal(ptr2, page_size, 0), 0); + + /* Make first VMA mergeable upon mseal. */ + ASSERT_EQ(mprotect(ptr, page_size, + PROT_READ | PROT_WRITE | PROT_EXEC), 0); + /* + * At this point we have: + * + * |-----------|-----------|-----------| + * | RWE | RWES | RO | + * |-----------|-----------|-----------| + * ptr ptr2 ptr3 + * + * Now mseal all of the VMAs. + */ + ASSERT_EQ(sys_mseal(ptr, 3 * page_size, 0), 0); + + /* + * We should end up with: + * + * |-----------------------|-----------| + * | RWES | ROS | + * |-----------------------|-----------| + * ptr ptr3 + */ + ASSERT_TRUE(find_vma_procmap(procmap, ptr)); + ASSERT_EQ(procmap->query.vma_start, (unsigned long)ptr); + ASSERT_EQ(procmap->query.vma_end, (unsigned long)ptr + 2 * page_size); +} + TEST_F(merge_with_fork, mremap_faulted_to_unfaulted_prev) { struct procmap_fd *procmap = &self->procmap; |