From 9cb429d692b341e972b12e6cd097364050ebbb26 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Tue, 24 Jul 2012 01:19:31 +0000 Subject: tcp: early_demux fixes 1) Remove a non needed pskb_may_pull() in tcp_v4_early_demux() and fix a potential bug if skb->head was reallocated (iph & th pointers were not reloaded) TCP stack will pull/check headers anyway. 2) must reload iph in ip_rcv_finish() after early_demux() call since skb->head might have changed. 3) skb->dev->ifindex can be now replaced by skb->skb_iif Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller --- net/ipv4/ip_input.c | 5 ++++- net/ipv4/tcp_ipv4.c | 9 ++------- 2 files changed, 6 insertions(+), 8 deletions(-) (limited to 'net/ipv4') diff --git a/net/ipv4/ip_input.c b/net/ipv4/ip_input.c index 4ebc6fe..93134b0 100644 --- a/net/ipv4/ip_input.c +++ b/net/ipv4/ip_input.c @@ -326,8 +326,11 @@ static int ip_rcv_finish(struct sk_buff *skb) rcu_read_lock(); ipprot = rcu_dereference(inet_protos[protocol]); - if (ipprot && ipprot->early_demux) + if (ipprot && ipprot->early_demux) { ipprot->early_demux(skb); + /* must reload iph, skb->head might have changed */ + iph = ip_hdr(skb); + } rcu_read_unlock(); } diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c index 3e30548..b6b07c9 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -1686,7 +1686,6 @@ void tcp_v4_early_demux(struct sk_buff *skb) struct net *net = dev_net(skb->dev); const struct iphdr *iph; const struct tcphdr *th; - struct net_device *dev; struct sock *sk; if (skb->pkt_type != PACKET_HOST) @@ -1701,14 +1700,10 @@ void tcp_v4_early_demux(struct sk_buff *skb) if (th->doff < sizeof(struct tcphdr) / 4) return; - if (!pskb_may_pull(skb, ip_hdrlen(skb) + th->doff * 4)) - return; - - dev = skb->dev; sk = __inet_lookup_established(net, &tcp_hashinfo, iph->saddr, th->source, iph->daddr, ntohs(th->dest), - dev->ifindex); + skb->skb_iif); if (sk) { skb->sk = sk; skb->destructor = sock_edemux; @@ -1718,7 +1713,7 @@ void tcp_v4_early_demux(struct sk_buff *skb) if (dst) dst = dst_check(dst, 0); if (dst && - icsk->rx_dst_ifindex == dev->ifindex) + icsk->rx_dst_ifindex == skb->skb_iif) skb_dst_set_noref(skb, dst); } } -- cgit v1.1