From 55f08149b0ebdd3ed44f9b361829ca924c35e3a8 Mon Sep 17 00:00:00 2001 From: Pravin B Shelar Date: Wed, 25 Sep 2013 09:57:47 -0700 Subject: [PATCH] ip_tunnel: Do not use stale inner_iph pointer. [ Upstream commit d4a71b155c12d0d429c6b69d94076d6d57e2a7a7 ] While sending packet skb_cow_head() can change skb header which invalidates inner_iph pointer to skb header. Following patch avoid using it. Found by code inspection. This bug was introduced by commit 0e6fbc5b6c6218 (ip_tunnels: extend iptunnel_xmit()). Signed-off-by: Pravin B Shelar Acked-by: Eric Dumazet Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/ipv4/ip_tunnel.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/net/ipv4/ip_tunnel.c b/net/ipv4/ip_tunnel.c index ca1cb2d5f6e2b..bb7cf05645894 100644 --- a/net/ipv4/ip_tunnel.c +++ b/net/ipv4/ip_tunnel.c @@ -626,6 +626,7 @@ void ip_tunnel_xmit(struct sk_buff *skb, struct net_device *dev, tunnel->err_count = 0; } + tos = ip_tunnel_ecn_encap(tos, inner_iph, skb); ttl = tnl_params->ttl; if (ttl == 0) { if (skb->protocol == htons(ETH_P_IP)) @@ -655,7 +656,7 @@ void ip_tunnel_xmit(struct sk_buff *skb, struct net_device *dev, err = iptunnel_xmit(dev_net(dev), rt, skb, fl4.saddr, fl4.daddr, protocol, - ip_tunnel_ecn_encap(tos, inner_iph, skb), ttl, df); + tos, ttl, df); iptunnel_xmit_stats(err, &dev->stats, dev->tstats); return; -- 2.47.2