From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sergei Shtylyov Subject: Re: [PATCH v2] ipv6: Fix protocol resubmission Date: Fri, 29 May 2015 23:27:56 +0300 Message-ID: <5568CBCC.1080503@cogentembedded.com> References: <1432929886-14259-1-git-send-email-johunt@akamai.com> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, tom@herbertland.com To: Josh Hunt , davem@davemloft.net Return-path: Received: from mail-la0-f50.google.com ([209.85.215.50]:33114 "EHLO mail-la0-f50.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1422659AbbE2U2E (ORCPT ); Fri, 29 May 2015 16:28:04 -0400 Received: by labpy14 with SMTP id py14so52425726lab.0 for ; Fri, 29 May 2015 13:28:03 -0700 (PDT) In-Reply-To: <1432929886-14259-1-git-send-email-johunt@akamai.com> Sender: netdev-owner@vger.kernel.org List-ID: Hello. On 05/29/2015 11:04 PM, Josh Hunt wrote: > I came across this problem while trying to use UDP encapsulation with IPv6. The > change below fixes that, but it was not immediately apparent if there are any > other protocols relying on this broken behavior. FWIW the behavior below now > matches IPv4. > Josh Need "Signed-off-by:" line insted of this. > v2: Actually sets nexthdr so we can use it ;) Normally goes after ---, not before. > --- > UDP encapsulation is broken on IPv6 because it expects when it returns a negative > value that the packet will be resubmitted to the stack with the handler corresponding > to the return value. The check currently looks for return values > 0 and then resubmits. > This patch fixes that check and also moves the resubmit label to take advantage of > the return code identifying the next protocol we want to process. > Signed-off-by: Josh Hunt > --- > net/ipv6/ip6_input.c | 7 ++++--- > 1 file changed, 4 insertions(+), 3 deletions(-) > diff --git a/net/ipv6/ip6_input.c b/net/ipv6/ip6_input.c > index f2e464e..e16c289 100644 > --- a/net/ipv6/ip6_input.c > +++ b/net/ipv6/ip6_input.c [...] > @@ -246,9 +246,10 @@ resubmit: > goto discard; > > ret = ipprot->handler(skb); > - if (ret > 0) > + if (ret < 0) { > + nexthdr = -ret; > goto resubmit; > - else if (ret == 0) > + } else if (ret == 0) > IP6_INC_STATS_BH(net, idev, IPSTATS_MIB_INDELIVERS); The CodingStyle dictates that all branches must have {} if at least one has them. [...] WBR, Sergei