From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sergei Shtylyov Subject: Re: [PATCH net v2] ip_tunnel: Set network header properly for IP_ECN_decapsulate() Date: Sun, 04 May 2014 19:13:12 +0400 Message-ID: <53665908.5080604@cogentembedded.com> References: Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit To: Ying Cai , netdev , Neal Cardwell , Eric Dumazet , pshelar@nicira.com Return-path: Received: from mail-la0-f42.google.com ([209.85.215.42]:40078 "EHLO mail-la0-f42.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750863AbaEDPNK (ORCPT ); Sun, 4 May 2014 11:13:10 -0400 Received: by mail-la0-f42.google.com with SMTP id pn19so626776lab.15 for ; Sun, 04 May 2014 08:13:08 -0700 (PDT) In-Reply-To: Sender: netdev-owner@vger.kernel.org List-ID: Hello. On 04-05-2014 9:40, Ying Cai wrote: > In ip_tunnel_rcv(), set skb->network_header to inner IP header > before IP_ECN_decapsulate(). > Without the fix, IP_ECN_decapsulate() takes outer IP header as > inner IP header, possibly causing error messages or packet drops. > Note that this skb_reset_network_header() call was in this spot when > the original feature for checking consistency of ECN bits through > tunnels was added in eccc1bb8d4b4 ("tunnel: drop packet if ECN present > with not-ECT"). It was only removed from this spot in 3d7b46cd20e3 > ("ip_tunnel: push generic protocol handling to ip_tunnel module."). > Fixes: 3d7b46cd20e3 ("ip_tunnel: push generic protocol handling to > ip_tunnel module.") > Reported-by: Neal Cardwell > Signed-off-by: Ying Cai > Acked-by: Neal Cardwell > --- > net/ipv4/ip_tunnel.c | 2 ++ > 1 file changed, 2 insertions(+) > diff --git a/net/ipv4/ip_tunnel.c b/net/ipv4/ip_tunnel.c > index fa5b751..b3f8597 100644 > --- a/net/ipv4/ip_tunnel.c > +++ b/net/ipv4/ip_tunnel.c > @@ -442,6 +442,8 @@ int ip_tunnel_rcv(struct ip_tunnel *tunnel, struct > sk_buff *skb, > tunnel->i_seqno = ntohl(tpi->seq) + 1; > } > > + skb_reset_network_header(skb); > + > err = IP_ECN_decapsulate(iph, skb); > if (unlikely(err)) { > if (log_ecn_error) The path is seriously whitespace-damaged. See Documentation/email-clients.txt in the kernel tree. WBR, Sergei