Commit 67203f3f authored by Pedro Falcato's avatar Pedro Falcato Committed by Andrew Morton
Browse files

selftests/mm: add mseal test for no-discard madvise 

Add an mseal test for madvise() operations that aren't considered
"discard" (e.g purely advisory ops such as MADV_RANDOM).

[pedro.falcato@gmail.com: adjust the mseal test's plan]
  Link: https://lkml.kernel.org/r/20240807203724.2686144-1-pedro.falcato@gmail.com
Link: https://lkml.kernel.org/r/20240807173336.2523757-3-pedro.falcato@gmail.com


Signed-off-by: default avatarPedro Falcato <pedro.falcato@gmail.com>
Tested-by: default avatarJeff Xu <jeffxu@chromium.org>
Reviewed-by: default avatarJeff Xu <jeffxu@chromium.org>
Cc: Kees Cook <kees@kernel.org>
Cc: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent cc0a0f98

tools/testing/selftests/mm/mseal_test.c

+35 −1
Original line number Diff line number Diff line
@@ -1731,6 +1731,38 @@ static void test_seal_discard_ro_anon(bool seal) 
	REPORT_TEST_PASS();

}



static void test_seal_madvise_nodiscard(bool seal)

{

	void *ptr;

	unsigned long page_size = getpagesize();

	unsigned long size = 4 * page_size;

	int ret;



	setup_single_address(size, &ptr);

	FAIL_TEST_IF_FALSE(ptr != (void *)-1);



	if (seal) {

		ret = seal_single_address(ptr, size);

		FAIL_TEST_IF_FALSE(!ret);

	}



	/*

	 * Test a random madvise flag like MADV_RANDOM that does not touch page

	 * contents (and thus should work for msealed VMAs). RANDOM also happens to

	 * share bits with other discard-ish flags like REMOVE.

	 */

	ret = sys_madvise(ptr, size, MADV_RANDOM);

	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();

}



int main(int argc, char **argv)

{

	bool test_seal = seal_support();
@@ -1743,7 +1775,7 @@ int main(int argc, char **argv) 
	if (!pkey_supported())

		ksft_print_msg("PKEY not supported\n");



	ksft_set_plan(80);

	ksft_set_plan(82);



	test_seal_addseal();

	test_seal_unmapped_start();
@@ -1822,6 +1854,8 @@ int main(int argc, char **argv) 
	test_seal_mremap_move_fixed_zero(true);

	test_seal_mremap_move_dontunmap_anyaddr(false);

	test_seal_mremap_move_dontunmap_anyaddr(true);

	test_seal_madvise_nodiscard(false);

	test_seal_madvise_nodiscard(true);

	test_seal_discard_ro_anon(false);

	test_seal_discard_ro_anon(true);

	test_seal_discard_ro_anon_on_rw(false);