From: Li RongQing <roy.qing.li@gmail.com>
Date: Sat, 18 Oct 2014 09:27:42 +0000 (+0800)
Subject: ipv6: fix a potential use after free in ip6_offload.c
X-Git-Tag: v3.18-rc1~10^2~2
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=fc6fb41cd64fd810bcc69fe9776d2f500778f38f;p=karo-tx-linux.git

ipv6: fix a potential use after free in ip6_offload.c

pskb_may_pull() maybe change skb->data and make opth pointer oboslete,
so set the opth again

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>
---

diff --git a/net/ipv6/ip6_offload.c b/net/ipv6/ip6_offload.c
index 9034f76ae013..91014d32488d 100644
--- a/net/ipv6/ip6_offload.c
+++ b/net/ipv6/ip6_offload.c
@@ -46,6 +46,7 @@ static int ipv6_gso_pull_exthdrs(struct sk_buff *skb, int proto)
 		if (unlikely(!pskb_may_pull(skb, len)))
 			break;
 
+		opth = (void *)skb->data;
 		proto = opth->nexthdr;
 		__skb_pull(skb, len);
 	}