Add a test to verify that detached mounts behave correctly.
Signed-off-by: Christian Brauner <brauner@xxxxxxxxxx>
---
.../selftests/mount_setattr/mount_setattr_test.c | 49 ++++++++++++++++++++++
1 file changed, 49 insertions(+)
diff --git a/tools/testing/selftests/mount_setattr/mount_setattr_test.c b/tools/testing/selftests/mount_setattr/mount_setattr_test.c
index 0641d2e22e02..082fdf19a9be 100644
--- a/tools/testing/selftests/mount_setattr/mount_setattr_test.c
+++ b/tools/testing/selftests/mount_setattr/mount_setattr_test.c
@@ -1829,4 +1829,53 @@ TEST_F(mount_setattr, mount_detached_mount_on_detached_mount_then_close)
EXPECT_EQ(close(fd_tree_subdir), 0);
}
+TEST_F(mount_setattr, mount_detached_mount_on_detached_mount_and_attach)
+{
+ int fd_tree_base = -EBADF, fd_tree_subdir = -EBADF;
+ struct statx stx;
+ __u64 mnt_id = 0;
+
+ 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, STATX_MNT_ID_UNIQUE, &stx), 0);
+ ASSERT_TRUE(stx.stx_attributes & STATX_ATTR_MOUNT_ROOT);
+ ASSERT_TRUE(stx.stx_mask & STATX_MNT_ID_UNIQUE);
+ mnt_id = stx.stx_mnt_id;
+
+ ASSERT_NE(move_mount(fd_tree_subdir, "", fd_tree_base, "", MOVE_MOUNT_F_EMPTY_PATH | MOVE_MOUNT_T_EMPTY_PATH), 0);
+
+ ASSERT_EQ(move_mount(fd_tree_base, "", -EBADF, "/tmp/target1", MOVE_MOUNT_F_EMPTY_PATH), 0);
+ ASSERT_EQ(statx(-EBADF, "/tmp/target1", 0, STATX_MNT_ID_UNIQUE, &stx), 0);
+ ASSERT_TRUE(stx.stx_attributes & STATX_ATTR_MOUNT_ROOT);
+ ASSERT_TRUE(stx.stx_mask & STATX_MNT_ID_UNIQUE);
+ ASSERT_EQ(stx.stx_mnt_id, mnt_id);
+
+ EXPECT_EQ(close(fd_tree_base), 0);
+ EXPECT_EQ(close(fd_tree_subdir), 0);
+}
+
TEST_HARNESS_MAIN
--
2.47.2
