The patch titled Subject: selftests/mm: add more mseal traversal tests has been added to the -mm mm-unstable branch. Its filename is selftests-mm-add-more-mseal-traversal-tests.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/selftests-mm-add-more-mseal-traversal-tests.patch This patch will later appear in the mm-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next via the mm-everything branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there every 2-3 working days ------------------------------------------------------ From: Pedro Falcato <pedro.falcato@xxxxxxxxx> Subject: selftests/mm: add more mseal traversal tests Date: Sat, 17 Aug 2024 01:18:34 +0100 Add more mseal traversal tests across VMAs, where we could possibly screw up sealing checks. These test more across-vma traversal for mprotect, munmap and madvise. Particularly, we test for the case where a regular VMA is followed by a sealed VMA. Link: https://lkml.kernel.org/r/20240817-mseal-depessimize-v3-7-d8d2e037df30@xxxxxxxxx Signed-off-by: Pedro Falcato <pedro.falcato@xxxxxxxxx> Reviewed-by: Liam R. Howlett <Liam.Howlett@xxxxxxxxxx> Cc: Jeff Xu <jeffxu@xxxxxxxxxxxx> Cc: Kees Cook <kees@xxxxxxxxxx> Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Cc: Lorenzo Stoakes <lorenzo.stoakes@xxxxxxxxxx> Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx> Cc: Shuah Khan <shuah@xxxxxxxxxx> Cc: Vlastimil Babka <vbabka@xxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- tools/testing/selftests/mm/mseal_test.c | 111 +++++++++++++++++++++- 1 file changed, 110 insertions(+), 1 deletion(-) --- a/tools/testing/selftests/mm/mseal_test.c~selftests-mm-add-more-mseal-traversal-tests +++ a/tools/testing/selftests/mm/mseal_test.c @@ -766,6 +766,42 @@ static void test_seal_mprotect_partial_m REPORT_TEST_PASS(); } +static void test_seal_mprotect_partial_mprotect_tail(bool seal) +{ + void *ptr; + unsigned long page_size = getpagesize(); + unsigned long size = 2 * page_size; + int ret; + int prot; + + /* + * Check if a partial mseal (that results in two vmas) works correctly. + * It might mprotect the first, but it'll never touch the second (msealed) vma. + */ + + setup_single_address(size, &ptr); + FAIL_TEST_IF_FALSE(ptr != (void *)-1); + + if (seal) { + ret = sys_mseal(ptr + page_size, size); + FAIL_TEST_IF_FALSE(!ret); + } + + ret = sys_mprotect(ptr, size, PROT_EXEC); + if (seal) + FAIL_TEST_IF_FALSE(ret < 0); + else + FAIL_TEST_IF_FALSE(!ret); + + if (seal) { + FAIL_TEST_IF_FALSE(get_vma_size(ptr + page_size, &prot) > 0); + FAIL_TEST_IF_FALSE(prot == 0x4); + } + + REPORT_TEST_PASS(); +} + + static void test_seal_mprotect_two_vma_with_gap(bool seal) { void *ptr; @@ -983,6 +1019,41 @@ static void test_seal_munmap_vma_with_ga REPORT_TEST_PASS(); } +static void test_seal_munmap_partial_across_vmas(bool seal) +{ + void *ptr; + unsigned long page_size = getpagesize(); + unsigned long size = 2 * page_size; + int ret; + int prot; + + /* + * Check if a partial mseal (that results in two vmas) works correctly. + * It might unmap the first, but it'll never unmap the second (msealed) vma. + */ + + setup_single_address(size, &ptr); + FAIL_TEST_IF_FALSE(ptr != (void *)-1); + + if (seal) { + ret = sys_mseal(ptr + page_size, size); + FAIL_TEST_IF_FALSE(!ret); + } + + ret = sys_munmap(ptr, size); + if (seal) + FAIL_TEST_IF_FALSE(ret < 0); + else + FAIL_TEST_IF_FALSE(!ret); + + if (seal) { + FAIL_TEST_IF_FALSE(get_vma_size(ptr + page_size, &prot) > 0); + FAIL_TEST_IF_FALSE(prot == 0x4); + } + + REPORT_TEST_PASS(); +} + static void test_munmap_start_freed(bool seal) { void *ptr; @@ -1735,6 +1806,37 @@ static void test_seal_discard_ro_anon(bo REPORT_TEST_PASS(); } +static void test_seal_discard_across_vmas(bool seal) +{ + void *ptr; + unsigned long page_size = getpagesize(); + unsigned long size = 2 * page_size; + int ret; + + setup_single_address(size, &ptr); + FAIL_TEST_IF_FALSE(ptr != (void *)-1); + + if (seal) { + ret = seal_single_address(ptr + page_size, page_size); + FAIL_TEST_IF_FALSE(!ret); + } + + ret = sys_madvise(ptr, size, MADV_DONTNEED); + if (seal) + FAIL_TEST_IF_FALSE(ret < 0); + else + FAIL_TEST_IF_FALSE(!ret); + + ret = sys_munmap(ptr, size); + if (seal) + FAIL_TEST_IF_FALSE(ret < 0); + else + FAIL_TEST_IF_FALSE(!ret); + + REPORT_TEST_PASS(); +} + + static void test_seal_madvise_nodiscard(bool seal) { void *ptr; @@ -1779,7 +1881,7 @@ int main(int argc, char **argv) if (!pkey_supported()) ksft_print_msg("PKEY not supported\n"); - ksft_set_plan(82); + ksft_set_plan(88); test_seal_addseal(); test_seal_unmapped_start(); @@ -1825,12 +1927,17 @@ int main(int argc, char **argv) test_seal_mprotect_split(false); test_seal_mprotect_split(true); + test_seal_mprotect_partial_mprotect_tail(false); + test_seal_mprotect_partial_mprotect_tail(true); + test_seal_munmap(false); test_seal_munmap(true); test_seal_munmap_two_vma(false); test_seal_munmap_two_vma(true); test_seal_munmap_vma_with_gap(false); test_seal_munmap_vma_with_gap(true); + test_seal_munmap_partial_across_vmas(false); + test_seal_munmap_partial_across_vmas(true); test_munmap_start_freed(false); test_munmap_start_freed(true); @@ -1862,6 +1969,8 @@ int main(int argc, char **argv) test_seal_madvise_nodiscard(true); test_seal_discard_ro_anon(false); test_seal_discard_ro_anon(true); + test_seal_discard_across_vmas(false); + test_seal_discard_across_vmas(true); test_seal_discard_ro_anon_on_rw(false); test_seal_discard_ro_anon_on_rw(true); test_seal_discard_ro_anon_on_shared(false); _ Patches currently in -mm which might be from pedro.falcato@xxxxxxxxx are selftests-mm-add-mseal-test-for-no-discard-madvise.patch selftests-mm-add-mseal-test-for-no-discard-madvise-fix.patch mm-move-can_modify_vma-to-mm-vmah.patch mm-munmap-replace-can_modify_mm-with-can_modify_vma.patch mm-mprotect-replace-can_modify_mm-with-can_modify_vma.patch mm-mremap-replace-can_modify_mm-with-can_modify_vma.patch mseal-replace-can_modify_mm_madv-with-a-vma-variant.patch mm-remove-can_modify_mm.patch selftests-mm-add-more-mseal-traversal-tests.patch