ipv4: early demux should be aware of fragments

We should not assume a valid protocol header is present,
as this is not the case for IPv4 fragments.

Lets avoid extra cache line misses and potential bugs
if we actually find a socket and incorrectly uses its dst.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Eric Dumazet 2016-01-26 16:59:42 -08:00 committed by David S. Miller
parent b64438853f
commit 63e51b6a24
1 changed files with 4 additions and 1 deletions

View File

@ -316,7 +316,10 @@ static int ip_rcv_finish(struct net *net, struct sock *sk, struct sk_buff *skb)
const struct iphdr *iph = ip_hdr(skb);
struct rtable *rt;
if (sysctl_ip_early_demux && !skb_dst(skb) && !skb->sk) {
if (sysctl_ip_early_demux &&
!skb_dst(skb) &&
!skb->sk &&
!ip_is_fragment(iph)) {
const struct net_protocol *ipprot;
int protocol = iph->protocol;