sysfs: fail dentry revalidation after namespace change fix
don't assume that KOBJ_NS_TYPE_NONE==0. Also save a test-n-branch.
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Glauber Costa <glommer@parallels.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Serge E. Hallyn <serge.hallyn@ubuntu.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c
index c0bf38a..1cdfb53 100644
--- a/fs/sysfs/dir.c
+++ b/fs/sysfs/dir.c
@@ -329,10 +329,12 @@
/* The sysfs dirent has been moved to a different namespace */
type = KOBJ_NS_TYPE_NONE;
- if (sd->s_parent)
+ if (sd->s_parent) {
type = sysfs_ns_type(sd->s_parent);
- if (type && (sysfs_info(dentry->d_sb)->ns[type] != sd->s_ns))
- goto out_bad;
+ if (type != KOBJ_NS_TYPE_NONE &&
+ sysfs_info(dentry->d_sb)->ns[type] != sd->s_ns)
+ goto out_bad;
+ }
mutex_unlock(&sysfs_mutex);
out_valid: