Commit f28bdd1b authored by Pedro Falcato's avatar Pedro Falcato Committed by Andrew Morton
Browse files

selftests/mm: add more mseal traversal tests 

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.

[akpm@linux-foundation.org: remove incorrect comment, per review]
[akpm@linux-foundation.org: remove the correct comment, per Pedro]
[pedro.falcato@gmail.com: fix mseal's length]
  Link: https://lkml.kernel.org/r/vc4czyuemmu3kylqb4ctaga6y5yvondlyabimx6jvljlw2fkea@djawlllf45xa
Link: https://lkml.kernel.org/r/20240817-mseal-depessimize-v3-7-d8d2e037df30@gmail.com


Signed-off-by: default avatarPedro Falcato <pedro.falcato@gmail.com>
Reviewed-by: default avatarLiam R. Howlett <Liam.Howlett@Oracle.com>
Reviewed-by: default avatarLorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Jeff Xu <jeffxu@chromium.org>
Cc: Kees Cook <kees@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent 5b3db2b8

tools/testing/selftests/mm/mseal_test.c

+105 −1
Original line number Diff line number Diff line
@@ -777,6 +777,42 @@ static void test_seal_mprotect_partial_mprotect(bool seal) 
	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, page_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;
@@ -994,6 +1030,36 @@ static void test_seal_munmap_vma_with_gap(bool seal) 
	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;



	setup_single_address(size, &ptr);

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



	if (seal) {

		ret = sys_mseal(ptr + page_size, page_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;
@@ -1746,6 +1812,37 @@ static void test_seal_discard_ro_anon(bool seal) 
	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;
@@ -1790,7 +1887,7 @@ 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();
@@ -1836,12 +1933,17 @@ 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);
@@ -1873,6 +1975,8 @@ 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);