From: Andrew Morton <akpm@linux-foundation.org>
Date: Mon, 9 Jul 2012 23:13:36 +0000 (-0700)
Subject: sysfs: fail dentry revalidation after namespace change fix
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=17f79be93d95bb0e46bd08681ec9c9e601869c15;p=GitHub%2FLineageOS%2Fandroid_kernel_motorola_exynos9610.git

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 c0bf38a21caa..1cdfb53199aa 100644
--- a/fs/sysfs/dir.c
+++ b/fs/sysfs/dir.c
@@ -329,10 +329,12 @@ static int sysfs_dentry_revalidate(struct dentry *dentry, struct nameidata *nd)
 
 	/* 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: