don't bother with propagate_mnt() unless the target is shared
If the dest_mnt is not shared, propagate_mnt() does nothing -
there's no mounts to propagate to and thus no copies to create.
Might as well don't bother calling it in that case.
Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/namespace.c b/fs/namespace.c
index 9db3ce3..d3fb9f0 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -1653,16 +1653,14 @@
err = invent_group_ids(source_mnt, true);
if (err)
goto out;
- }
- err = propagate_mnt(dest_mnt, dest_mp, source_mnt, &tree_list);
- if (err)
- goto out_cleanup_ids;
-
- lock_mount_hash();
-
- if (IS_MNT_SHARED(dest_mnt)) {
+ err = propagate_mnt(dest_mnt, dest_mp, source_mnt, &tree_list);
+ if (err)
+ goto out_cleanup_ids;
+ lock_mount_hash();
for (p = source_mnt; p; p = next_mnt(p, source_mnt))
set_mnt_shared(p);
+ } else {
+ lock_mount_hash();
}
if (parent_path) {
detach_mnt(source_mnt, parent_path);
@@ -1685,8 +1683,7 @@
return 0;
out_cleanup_ids:
- if (IS_MNT_SHARED(dest_mnt))
- cleanup_group_ids(source_mnt, NULL);
+ cleanup_group_ids(source_mnt, NULL);
out:
return err;
}