From: Li RongQing <roy.qing.li@gmail.com>
Date: Wed, 18 Jun 2014 05:46:02 +0000 (+0800)
Subject: 8021q: fix a potential memory leak
X-Git-Tag: v3.15.7~69
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=f8e4d67de57bed98a22f2f55d45224497c6a0338;p=thirdparty%2Fkernel%2Fstable.git

8021q: fix a potential memory leak

[ Upstream commit 916c1689a09bc1ca81f2d7a34876f8d35aadd11b ]

skb_cow called in vlan_reorder_header does not free the skb when it failed,
and vlan_reorder_header returns NULL to reset original skb when it is called
in vlan_untag, lead to a memory leak.

Signed-off-by: Li RongQing <roy.qing.li@gmail.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/net/8021q/vlan_core.c b/net/8021q/vlan_core.c
index 3c32bd257b739..80e0d0360b806 100644
--- a/net/8021q/vlan_core.c
+++ b/net/8021q/vlan_core.c
@@ -114,8 +114,11 @@ EXPORT_SYMBOL(vlan_dev_vlan_proto);
 
 static struct sk_buff *vlan_reorder_header(struct sk_buff *skb)
 {
-	if (skb_cow(skb, skb_headroom(skb)) < 0)
+	if (skb_cow(skb, skb_headroom(skb)) < 0) {
+		kfree_skb(skb);
 		return NULL;
+	}
+
 	memmove(skb->data - ETH_HLEN, skb->data - VLAN_ETH_HLEN, 2 * ETH_ALEN);
 	skb->mac_header += VLAN_HLEN;
 	return skb;