[PATCH v8 6/9] selftests/landlock: Test open() and ftruncate() in multiple scenarios

[Mickaël Salaün]

Clean test cases and complete coverage, great!

On 01/10/2022 17:49, Günther Noack wrote:
> This test uses multiple fixture variants to exercise a broader set of
> scnenarios.
> 
> Signed-off-by: Günther Noack <gnoack3000 at gmail.com>
> ---
>   tools/testing/selftests/landlock/fs_test.c | 96 ++++++++++++++++++++++
>   1 file changed, 96 insertions(+)
> 
> diff --git a/tools/testing/selftests/landlock/fs_test.c b/tools/testing/selftests/landlock/fs_test.c
> index 718543fd3dfc..308f6f36e8c0 100644
> --- a/tools/testing/selftests/landlock/fs_test.c
> +++ b/tools/testing/selftests/landlock/fs_test.c
> @@ -3445,6 +3445,102 @@ TEST_F_FORK(layout1, ftruncate)
>   	ASSERT_EQ(0, close(fd_layer3));
>   }
>   
> +/* clang-format off */
> +FIXTURE(ftruncate) {};
> +/* clang-format on */
> +
> +FIXTURE_SETUP(ftruncate)
> +{
> +	prepare_layout(_metadata);
> +	create_file(_metadata, file1_s1d1);
> +}
> +
> +FIXTURE_TEARDOWN(ftruncate)
> +{
> +	EXPECT_EQ(0, remove_path(file1_s1d1));
> +	cleanup_layout(_metadata);
> +}
> +
> +FIXTURE_VARIANT(ftruncate)
> +{
> +	const __u64 handled;
> +	const __u64 permitted;
> +	const int expected_open_result;
> +	const int expected_ftruncate_result;
> +};
> +
> +/* clang-format off */
> +FIXTURE_VARIANT_ADD(ftruncate, w_w) {
> +	/* clang-format on */
> +	.handled = LANDLOCK_ACCESS_FS_WRITE_FILE,
> +	.permitted = LANDLOCK_ACCESS_FS_WRITE_FILE,
> +	.expected_open_result = 0,
> +	.expected_ftruncate_result = 0,
> +};
> +
> +/* clang-format off */
> +FIXTURE_VARIANT_ADD(ftruncate, t_t) {
> +	/* clang-format on */
> +	.handled = LANDLOCK_ACCESS_FS_TRUNCATE,
> +	.permitted = LANDLOCK_ACCESS_FS_TRUNCATE,
> +	.expected_open_result = 0,
> +	.expected_ftruncate_result = 0,
> +};
> +
> +/* clang-format off */
> +FIXTURE_VARIANT_ADD(ftruncate, wt_w) {
> +	/* clang-format on */
> +	.handled = LANDLOCK_ACCESS_FS_WRITE_FILE | LANDLOCK_ACCESS_FS_TRUNCATE,
> +	.permitted = LANDLOCK_ACCESS_FS_WRITE_FILE,
> +	.expected_open_result = 0,
> +	.expected_ftruncate_result = EACCES,
> +};
> +
> +/* clang-format off */
> +FIXTURE_VARIANT_ADD(ftruncate, wt_wt) {
> +	/* clang-format on */
> +	.handled = LANDLOCK_ACCESS_FS_WRITE_FILE | LANDLOCK_ACCESS_FS_TRUNCATE,
> +	.permitted = LANDLOCK_ACCESS_FS_WRITE_FILE |
> +		     LANDLOCK_ACCESS_FS_TRUNCATE,
> +	.expected_open_result = 0,
> +	.expected_ftruncate_result = 0,
> +};
> +
> +/* clang-format off */
> +FIXTURE_VARIANT_ADD(ftruncate, wt_t) {
> +	/* clang-format on */
> +	.handled = LANDLOCK_ACCESS_FS_WRITE_FILE | LANDLOCK_ACCESS_FS_TRUNCATE,
> +	.permitted = LANDLOCK_ACCESS_FS_TRUNCATE,
> +	.expected_open_result = EACCES,
> +};
> +
> +TEST_F_FORK(ftruncate, open_and_ftruncate)
> +{
> +	const char *const path = file1_s1d1;
> +	const struct rule rules[] = {
> +		{
> +			.path = path,
> +			.access = variant->permitted,
> +		},
> +		{},
> +	};
> +	int fd, ruleset_fd;
> +
> +	/* Enable Landlock. */
> +	ruleset_fd = create_ruleset(_metadata, variant->handled, rules);
> +	ASSERT_LE(0, ruleset_fd);
> +	enforce_ruleset(_metadata, ruleset_fd);
> +	ASSERT_EQ(0, close(ruleset_fd));
> +
> +	fd = open(path, O_WRONLY);
> +	EXPECT_EQ(variant->expected_open_result, (fd < 0 ? errno : 0));
> +	if (fd >= 0) {
> +		EXPECT_EQ(variant->expected_ftruncate_result,
> +			  test_ftruncate(fd));
> +		ASSERT_EQ(0, close(fd));
> +	}
> +}
> +
>   /* clang-format off */
>   FIXTURE(layout1_bind) {};
>   /* clang-format on */