From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755687AbbAWQFR (ORCPT ); Fri, 23 Jan 2015 11:05:17 -0500 Received: from mail-qc0-f170.google.com ([209.85.216.170]:62487 "EHLO mail-qc0-f170.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752085AbbAWQFO (ORCPT ); Fri, 23 Jan 2015 11:05:14 -0500 Message-ID: <54C27137.5010405@gmail.com> Date: Fri, 23 Jan 2015 11:05:11 -0500 From: Vlad Yasevich User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.3.0 MIME-Version: 1.0 To: Daniel Borkmann , Sun Paul CC: linux-sctp@vger.kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: Fwd: Question on SCTP ABORT chunk is generated when the association_max_retrans is reached References: <54C23581.9060809@redhat.com> In-Reply-To: <54C23581.9060809@redhat.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 01/23/2015 06:50 AM, Daniel Borkmann wrote: > Hi, > > On 01/23/2015 11:25 AM, Sun Paul wrote: > ... >> I would like to check the behave in LKSCTP. >> >> we are running DIAMETER message over SCTP, and we have set the >> parameter "net.sctp.association_max_retrans = 4" in the LinuxOS. >> >> We noticed that when remote peer have retry to send the same request >> for 4 times, the LKSCTP will initiate an ABORT chunk with reason >> "association exceeded its max_retrans count". >> >> We would like to know whether this is the correct behavior? is there >> any other option that we can alter in order to avoid the ABORT chunk >> being sent? > > I don't recall the RFC saying to send an ABORT, but let me double > check in the mean time. The RFC is silent on the matter. The abort got added in 3.8 so it's been there for a while. > > Hmm, untested, but could you try something like that? > > diff --git a/net/sctp/sm_sideeffect.c b/net/sctp/sm_sideeffect.c > index fef2acd..5ce198d 100644 > --- a/net/sctp/sm_sideeffect.c > +++ b/net/sctp/sm_sideeffect.c > @@ -584,7 +584,8 @@ static void sctp_cmd_assoc_failed(sctp_cmd_seq_t *commands, > sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, > SCTP_ULPEVENT(event)); > > - if (asoc->overall_error_count >= asoc->max_retrans) { > + if (asoc->overall_error_count >= asoc->max_retrans && > + error != SCTP_ERROR_NO_ERROR) { > abort = sctp_make_violation_max_retrans(asoc, chunk); > if (abort) > sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, This would pretty much stop all ABORTs due to excessive rtx. Might as well take the code out :). I was a bit concerned about this ABORT when it went in. -vlad