From: Yan, Zheng <zyan@redhat.com>
Date: Wed, 19 Nov 2014 07:50:34 +0000 (+0800)
Subject: vfs: fix reference leak in d_prune_aliases()
X-Git-Tag: v3.18-rc6~8^2~2
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=4a7795d35e252f38298980530e01e21867f8f856;p=karo-tx-linux.git

vfs: fix reference leak in d_prune_aliases()

In "d_prune_alias(): just lock the parent and call __dentry_kill()" the old
dget + d_drop + dput has been replaced with lock_parent + __dentry_kill;
unfortunately, dput() does more than just killing dentry - it also drops the
reference to parent.  New variant leaks that reference and needs dput(parent)
after killing the child off.

Signed-off-by: Yan, Zheng <zyan@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---

diff --git a/fs/dcache.c b/fs/dcache.c
index 3ffef7f4e5cd..5bc72b07fde2 100644
--- a/fs/dcache.c
+++ b/fs/dcache.c
@@ -778,6 +778,7 @@ restart:
 			struct dentry *parent = lock_parent(dentry);
 			if (likely(!dentry->d_lockref.count)) {
 				__dentry_kill(dentry);
+				dput(parent);
 				goto restart;
 			}
 			if (parent)