From e8d11678770b9bbdcc5c2a9b3a041d136575f322 Mon Sep 17 00:00:00 2001 From: Pravin B Shelar Date: Tue, 13 Aug 2013 01:41:06 -0700 Subject: [PATCH] ip_tunnel: Do not use inner ip-header-id for tunnel ip-header-id. [ Upstream commit 4221f40513233fa8edeef7fc82e44163fde03b9b ] Using inner-id for tunnel id is not safe in some rare cases. E.g. packets coming from multiple sources entering same tunnel can have same id. Therefore on tunnel packet receive we could have packets from two different stream but with same source and dst IP with same ip-id which could confuse ip packet reassembly. Following patch reverts optimization from commit 490ab08127 (IP_GRE: Fix IP-Identification.) Signed-off-by: Pravin B Shelar CC: Jarno Rajahalme CC: Ansis Atteka Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- drivers/net/vxlan.c | 2 +- include/net/ip_tunnels.h | 14 -------------- net/ipv4/ip_tunnel.c | 2 +- 3 files changed, 2 insertions(+), 16 deletions(-) diff --git a/drivers/net/vxlan.c b/drivers/net/vxlan.c index 57325f3..054489f 100644 --- a/drivers/net/vxlan.c +++ b/drivers/net/vxlan.c @@ -1090,7 +1090,7 @@ static netdev_tx_t vxlan_xmit_one(struct sk_buff *skb, struct net_device *dev, iph->daddr = dst; iph->saddr = fl4.saddr; iph->ttl = ttl ? : ip4_dst_hoplimit(&rt->dst); - tunnel_ip_select_ident(skb, old_iph, &rt->dst); + __ip_select_ident(iph, &rt->dst, (skb_shinfo(skb)->gso_segs ?: 1) - 1); nf_reset(skb); diff --git a/include/net/ip_tunnels.h b/include/net/ip_tunnels.h index 09b1360..a9942e1 100644 --- a/include/net/ip_tunnels.h +++ b/include/net/ip_tunnels.h @@ -141,20 +141,6 @@ static inline u8 ip_tunnel_ecn_encap(u8 tos, const struct iphdr *iph, return INET_ECN_encapsulate(tos, inner); } -static inline void tunnel_ip_select_ident(struct sk_buff *skb, - const struct iphdr *old_iph, - struct dst_entry *dst) -{ - struct iphdr *iph = ip_hdr(skb); - - /* Use inner packet iph-id if possible. */ - if (skb->protocol == htons(ETH_P_IP) && old_iph->id) - iph->id = old_iph->id; - else - __ip_select_ident(iph, dst, - (skb_shinfo(skb)->gso_segs ?: 1) - 1); -} - static inline void iptunnel_xmit(struct sk_buff *skb, struct net_device *dev) { int err; diff --git a/net/ipv4/ip_tunnel.c b/net/ipv4/ip_tunnel.c index cbfc37f..b7a4c21 100644 --- a/net/ipv4/ip_tunnel.c +++ b/net/ipv4/ip_tunnel.c @@ -686,7 +686,7 @@ void ip_tunnel_xmit(struct sk_buff *skb, struct net_device *dev, iph->daddr = fl4.daddr; iph->saddr = fl4.saddr; iph->ttl = ttl; - tunnel_ip_select_ident(skb, inner_iph, &rt->dst); + __ip_select_ident(iph, &rt->dst, (skb_shinfo(skb)->gso_segs ?: 1) - 1); iptunnel_xmit(skb, dev); return; -- 2.7.4