Add a test to verify that detached mounts behave correctly.
Signed-off-by: Christian Brauner <brauner@xxxxxxxxxx>
---
.../selftests/mount_setattr/mount_setattr_test.c | 31 ++++++++++++++++++++++
1 file changed, 31 insertions(+)
diff --git a/tools/testing/selftests/mount_setattr/mount_setattr_test.c b/tools/testing/selftests/mount_setattr/mount_setattr_test.c
index 082fdf19a9be..66eed84c6a01 100644
--- a/tools/testing/selftests/mount_setattr/mount_setattr_test.c
+++ b/tools/testing/selftests/mount_setattr/mount_setattr_test.c
@@ -1878,4 +1878,35 @@ TEST_F(mount_setattr, mount_detached_mount_on_detached_mount_and_attach)
EXPECT_EQ(close(fd_tree_subdir), 0);
}
+TEST_F(mount_setattr, move_mount_detached_fail)
+{
+ 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);
+
+ /* Attach the mount to the caller's mount namespace. */
+ ASSERT_EQ(move_mount(fd_tree_base, "", -EBADF, "/tmp/target1", MOVE_MOUNT_F_EMPTY_PATH), 0);
+
+ 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(-EBADF, "/tmp/B",
+ AT_NO_AUTOMOUNT | AT_SYMLINK_NOFOLLOW |
+ OPEN_TREE_CLOEXEC | OPEN_TREE_CLONE);
+ ASSERT_GE(fd_tree_subdir, 0);
+ ASSERT_EQ(statx(fd_tree_subdir, "BB", 0, 0, &stx), 0);
+ ASSERT_FALSE(stx.stx_attributes & STATX_ATTR_MOUNT_ROOT);
+
+ /* Not allowed to move an attached mount to a detached mount. */
+ ASSERT_NE(move_mount(fd_tree_base, "", fd_tree_subdir, "", MOVE_MOUNT_F_EMPTY_PATH | MOVE_MOUNT_T_EMPTY_PATH), 0);
+ ASSERT_EQ(errno, EINVAL);
+
+ EXPECT_EQ(close(fd_tree_base), 0);
+ EXPECT_EQ(close(fd_tree_subdir), 0);
+}
+
TEST_HARNESS_MAIN
--
2.47.2
