From mboxrd@z Thu Jan 1 00:00:00 1970 From: David L Stevens Subject: Re: [PATCH net-next 2/3] ipv6: mld: do not overwrite uri when receiving an mldv2 query Date: Thu, 25 Sep 2014 12:02:17 -0400 Message-ID: <54243C89.6060405@oracle.com> References: <1411455828-5196-1-git-send-email-dborkman@redhat.com> <1411455828-5196-3-git-send-email-dborkman@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: hannes@stressinduktion.org, netdev@vger.kernel.org To: Daniel Borkmann , davem@davemloft.net Return-path: Received: from aserp1040.oracle.com ([141.146.126.69]:21675 "EHLO aserp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753476AbaIYQCl (ORCPT ); Thu, 25 Sep 2014 12:02:41 -0400 In-Reply-To: <1411455828-5196-3-git-send-email-dborkman@redhat.com> Sender: netdev-owner@vger.kernel.org List-ID: While I can see the case you're making, I think the intent of MRC is violated by arbitrary URI. > 5.1.3. Maximum Response Code > > The Maximum Response Code field specifies the maximum time allowed > before sending a responding Report. >... > Small values of Maximum Response Delay allow MLDv2 routers to tune > the "leave latency" (the time between the moment the last node on a > link ceases to listen to a specific multicast address and the moment > the routing protocol is notified that there are no more listeners for > that address). Larger values, especially in the exponential range, > allow the tuning of the burstiness of MLD traffic on a link. If URI is larger than MRD, then a lost unsolicited report, or series, specifically will *not* propagate changes throughout the network in less than MRD*QRV, as intended. It was an intentional design choice, not required or prohibited by RFC. I'm not sure what problem you think it's causing, but if they are not equal, I think at least the URI should be enforced to <= MRD. The querier, IMO, should set these network-wide relevant parameters, not the individual hosts. Is there actually some bad effect from this? +-DLS