On Thu, Aug 29, 2024 at 09:43:51PM GMT, jeffxu@chromium.org wrote:
From: Jeff Xu jeffxu@chromium.org
Add sealing test to cover mmap for Expand/shrink across vmas. Reuse the same address in !MAP_FIXED case.
Signed-off-by: Jeff Xu jeffxu@chromium.org
tools/testing/selftests/mm/mseal_test.c | 125 +++++++++++++++++++++++- 1 file changed, 124 insertions(+), 1 deletion(-)
diff --git a/tools/testing/selftests/mm/mseal_test.c b/tools/testing/selftests/mm/mseal_test.c index ae06c354220d..d83538039e76 100644 --- a/tools/testing/selftests/mm/mseal_test.c +++ b/tools/testing/selftests/mm/mseal_test.c @@ -2222,6 +2222,122 @@ static void test_munmap_free_multiple_ranges(bool seal) REPORT_TEST_PASS(); } +static void test_seal_mmap_expand_seal_middle(bool seal) +{
- void *ptr;
- unsigned long page_size = getpagesize();
- unsigned long size = 12 * page_size;
- int ret;
- void *ret2;
- int prot;
- setup_single_address(size, &ptr);
- FAIL_TEST_IF_FALSE(ptr != (void *)-1);
- /* ummap last 4 pages. */
- ret = sys_munmap(ptr + 8 * page_size, 4 * page_size);
- FAIL_TEST_IF_FALSE(!ret);
- size = get_vma_size(ptr, &prot);
- FAIL_TEST_IF_FALSE(size == 8 * page_size);
- FAIL_TEST_IF_FALSE(prot == 0x4);
- if (seal) {
ret = sys_mseal(ptr + 4 * page_size, 4 * page_size);FAIL_TEST_IF_FALSE(!ret);- }
- /* use mmap to expand. */
- ret2 = mmap(ptr, 12 * page_size, PROT_READ,
MAP_ANONYMOUS | MAP_PRIVATE | MAP_FIXED, -1, 0);
This is not expansion, but overwriting. Expansion is allowed through an adjacent mmap + mseal (which will merge the two VMAs).
- if (seal) {
FAIL_TEST_IF_FALSE(ret2 == MAP_FAILED);FAIL_TEST_IF_FALSE(errno == EPERM);size = get_vma_size(ptr, &prot);FAIL_TEST_IF_FALSE(size == 4 * page_size);FAIL_TEST_IF_FALSE(prot == 0x4);size = get_vma_size(ptr + 4 * page_size, &prot);FAIL_TEST_IF_FALSE(size == 4 * page_size);FAIL_TEST_IF_FALSE(prot == 0x4);- } else
FAIL_TEST_IF_FALSE(ret2 == ptr);- REPORT_TEST_PASS();
+}
+static void test_seal_mmap_shrink_seal_middle(bool seal) +{
- void *ptr;
- unsigned long page_size = getpagesize();
- unsigned long size = 12 * page_size;
- int ret;
- void *ret2;
- int prot;
- setup_single_address(size, &ptr);
- FAIL_TEST_IF_FALSE(ptr != (void *)-1);
- if (seal) {
ret = sys_mseal(ptr + 4 * page_size, 4 * page_size);FAIL_TEST_IF_FALSE(!ret);- }
- /* use mmap to shrink. */
- ret2 = mmap(ptr, 7 * page_size, PROT_READ,
MAP_ANONYMOUS | MAP_PRIVATE | MAP_FIXED, -1, 0);
This is also a partial overwrite.
- if (seal) {
FAIL_TEST_IF_FALSE(ret2 == MAP_FAILED);FAIL_TEST_IF_FALSE(errno == EPERM);size = get_vma_size(ptr, &prot);FAIL_TEST_IF_FALSE(size == 4 * page_size);FAIL_TEST_IF_FALSE(prot == 0x4);size = get_vma_size(ptr + 4 * page_size, &prot);FAIL_TEST_IF_FALSE(size == 4 * page_size);FAIL_TEST_IF_FALSE(prot == 0x4);size = get_vma_size(ptr + 4 * page_size, &prot);FAIL_TEST_IF_FALSE(size == 4 * page_size);FAIL_TEST_IF_FALSE(prot == 0x4);- } else
FAIL_TEST_IF_FALSE(ret2 == ptr);- REPORT_TEST_PASS();
+}
+static void test_seal_mmap_reuse_addr(bool seal) +{
- void *ptr;
- unsigned long page_size = getpagesize();
- unsigned long size = page_size;
- int ret;
- void *ret2;
- int prot;
- setup_single_address(size, &ptr);
- FAIL_TEST_IF_FALSE(ptr != (void *)-1);
- if (seal) {
ret = sys_mseal(ptr, size);FAIL_TEST_IF_FALSE(!ret);- }
- /* use mmap to change protection. */
- ret2 = mmap(ptr, size, PROT_NONE,
MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
This is also an overwrite. You're semantically testing the same thing, and testing the same regions of code. These 3 tests are all kind of the same thing.