Commit 1245dfc8 authored Oct 17, 2014 by Li RongQing Committed by David S. Miller Oct 17, 2014

ipv4: fix a potential use after free in ip_tunnel_core.c



pskb_may_pull() maybe change skb->data and make eth pointer oboslete,
so set eth after pskb_may_pull()

Fixes:3d7b46cd("ip_tunnel: push generic protocol handling to ip_tunnel module")
Cc: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: Li RongQing <roy.qing.li@gmail.com>
Acked-by: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

parent f88e6714

net/ipv4/ip_tunnel_core.c

+2 −1

Original line number	Diff line number	Diff line
		@@ -91,11 +91,12 @@ int iptunnel_pull_header(struct sk_buff *skb, int hdr_len, __be16 inner_proto)
		skb_pull_rcsum(skb, hdr_len);

		if (inner_proto == htons(ETH_P_TEB)) {
		struct ethhdr eh = (struct ethhdr )skb->data;
		struct ethhdr *eh;

		if (unlikely(!pskb_may_pull(skb, ETH_HLEN)))
		return -ENOMEM;

		eh = (struct ethhdr *)skb->data;
		if (likely(ntohs(eh->h_proto) >= ETH_P_802_3_MIN))
		skb->protocol = eh->h_proto;
		else