Unverified Commit d83a55b8 authored by Christian Brauner's avatar Christian Brauner
Browse files

selftests: first test for mounting detached mounts onto detached mounts 

Add a test to verify that detached mounts behave correctly.

Link: https://lore.kernel.org/r/20250221-brauner-open_tree-v1-10-dbcfcb98c676@kernel.org


Signed-off-by: default avatarChristian Brauner <brauner@kernel.org>
parent 21107723

tools/testing/selftests/mount_setattr/mount_setattr_test.c

+40 −0
Original line number Diff line number Diff line
@@ -1789,4 +1789,44 @@ TEST_F(mount_setattr, open_tree_detached_fail3) 
	ASSERT_EQ(errno, EINVAL);

}



TEST_F(mount_setattr, mount_detached_mount_on_detached_mount_then_close)

{

	int fd_tree_base = -EBADF, fd_tree_subdir = -EBADF;

	struct statx stx;



	fd_tree_base = sys_open_tree(-EBADF, "/mnt",

				     AT_NO_AUTOMOUNT | AT_SYMLINK_NOFOLLOW |

				     OPEN_TREE_CLOEXEC | OPEN_TREE_CLONE);

	ASSERT_GE(fd_tree_base, 0);

	/*

	 * /mnt testing tmpfs

	 */

	ASSERT_EQ(statx(fd_tree_base, "A", 0, 0, &stx), 0);

	ASSERT_FALSE(stx.stx_attributes & STATX_ATTR_MOUNT_ROOT);



	fd_tree_subdir = sys_open_tree(fd_tree_base, "",

				       AT_NO_AUTOMOUNT | AT_SYMLINK_NOFOLLOW |

				       AT_EMPTY_PATH | OPEN_TREE_CLOEXEC |

				       OPEN_TREE_CLONE);

	ASSERT_GE(fd_tree_subdir, 0);

	/*

	 * /mnt testing tmpfs

	 */

	ASSERT_EQ(statx(fd_tree_subdir, "A", 0, 0, &stx), 0);

	ASSERT_FALSE(stx.stx_attributes & STATX_ATTR_MOUNT_ROOT);



	/*

	 * /mnt   testing tmpfs

	 * `-/mnt testing tmpfs

	 */

	ASSERT_EQ(move_mount(fd_tree_subdir, "", fd_tree_base, "", MOVE_MOUNT_F_EMPTY_PATH | MOVE_MOUNT_T_EMPTY_PATH), 0);

	ASSERT_EQ(statx(fd_tree_subdir, "", AT_EMPTY_PATH, 0, &stx), 0);

	ASSERT_TRUE(stx.stx_attributes & STATX_ATTR_MOUNT_ROOT);



	ASSERT_NE(move_mount(fd_tree_subdir, "", fd_tree_base, "", MOVE_MOUNT_F_EMPTY_PATH | MOVE_MOUNT_T_EMPTY_PATH), 0);



	EXPECT_EQ(close(fd_tree_base), 0);

	EXPECT_EQ(close(fd_tree_subdir), 0);

}



TEST_HARNESS_MAIN