Unverified Commit 12264f72 authored by Mickaël Salaün's avatar Mickaël Salaün
Browse files

selftests/landlock: Add test to check partial access in a mount tree 

Add layout1.refer_part_mount_tree_is_allowed to test the masked logical
issue regarding collect_domain_accesses() calls followed by the
is_access_to_paths_allowed() check in current_check_refer_path().  See
previous commit.

This test should work without the previous fix as well, but it enables
us to make sure future changes will not have impact regarding this
behavior.

Cc: Günther Noack <gnoack@google.com>
Link: https://lore.kernel.org/r/20250108154338.1129069-13-mic@digikod.net


Signed-off-by: default avatarMickaël Salaün <mic@digikod.net>
parent 058518c2

tools/testing/selftests/landlock/fs_test.c

+50 −4
Original line number Diff line number Diff line
@@ -85,6 +85,9 @@ static const char file1_s3d1[] = TMP_DIR "/s3d1/f1"; 
/* dir_s3d2 is a mount point. */

static const char dir_s3d2[] = TMP_DIR "/s3d1/s3d2";

static const char dir_s3d3[] = TMP_DIR "/s3d1/s3d2/s3d3";

static const char file1_s3d3[] = TMP_DIR "/s3d1/s3d2/s3d3/f1";

static const char dir_s3d4[] = TMP_DIR "/s3d1/s3d2/s3d4";

static const char file1_s3d4[] = TMP_DIR "/s3d1/s3d2/s3d4/f1";



/*

 * layout1 hierarchy:
@@ -108,8 +111,11 @@ static const char dir_s3d3[] = TMP_DIR "/s3d1/s3d2/s3d3"; 
 * │           └── f2

 * └── s3d1

 *     ├── f1

 *     └── s3d2

 *         └── s3d3

 *     └── s3d2 [mount point]

 *         ├── s3d3

 *         │   └── f1

 *         └── s3d4

 *             └── f1

 */



static bool fgrep(FILE *const inf, const char *const str)
@@ -358,7 +364,8 @@ static void create_layout1(struct __test_metadata *const _metadata) 
	ASSERT_EQ(0, mount_opt(&mnt_tmp, dir_s3d2));

	clear_cap(_metadata, CAP_SYS_ADMIN);



	ASSERT_EQ(0, mkdir(dir_s3d3, 0700));

	create_file(_metadata, file1_s3d3);

	create_file(_metadata, file1_s3d4);

}



static void remove_layout1(struct __test_metadata *const _metadata)
@@ -378,7 +385,8 @@ static void remove_layout1(struct __test_metadata *const _metadata) 
	EXPECT_EQ(0, remove_path(dir_s2d2));



	EXPECT_EQ(0, remove_path(file1_s3d1));

	EXPECT_EQ(0, remove_path(dir_s3d3));

	EXPECT_EQ(0, remove_path(file1_s3d3));

	EXPECT_EQ(0, remove_path(file1_s3d4));

	set_cap(_metadata, CAP_SYS_ADMIN);

	umount(dir_s3d2);

	clear_cap(_metadata, CAP_SYS_ADMIN);
@@ -2444,6 +2452,44 @@ TEST_F_FORK(layout1, refer_mount_root_deny) 
	EXPECT_EQ(0, close(root_fd));

}



TEST_F_FORK(layout1, refer_part_mount_tree_is_allowed)

{

	const struct rule layer1[] = {

		{

			/* Parent mount point. */

			.path = dir_s3d1,

			.access = LANDLOCK_ACCESS_FS_REFER |

				  LANDLOCK_ACCESS_FS_MAKE_REG,

		},

		{

			/*

			 * Removing the source file is allowed because its

			 * access rights are already a superset of the

			 * destination.

			 */

			.path = dir_s3d4,

			.access = LANDLOCK_ACCESS_FS_REFER |

				  LANDLOCK_ACCESS_FS_MAKE_REG |

				  LANDLOCK_ACCESS_FS_REMOVE_FILE,

		},

		{},

	};

	int ruleset_fd;



	ASSERT_EQ(0, unlink(file1_s3d3));

	ruleset_fd = create_ruleset(_metadata,

				    LANDLOCK_ACCESS_FS_REFER |

					    LANDLOCK_ACCESS_FS_MAKE_REG |

					    LANDLOCK_ACCESS_FS_REMOVE_FILE,

				    layer1);



	ASSERT_LE(0, ruleset_fd);

	enforce_ruleset(_metadata, ruleset_fd);

	ASSERT_EQ(0, close(ruleset_fd));



	ASSERT_EQ(0, rename(file1_s3d4, file1_s3d3));

}



TEST_F_FORK(layout1, reparent_link)

{

	const struct rule layer1[] = {