From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [PATCH net-next v2] net: ipv6: make sure multicast packets are not forwarded beyond the different scopes Date: Tue, 02 May 2017 14:59:23 -0400 (EDT) Message-ID: <20170502.145923.66844914584656456.davem@davemloft.net> References: <20170427071202.84403-1-donatas.abraitis@gmail.com> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, stable@vger.kernel.org To: donatas.abraitis@gmail.com Return-path: In-Reply-To: <20170427071202.84403-1-donatas.abraitis@gmail.com> Sender: stable-owner@vger.kernel.org List-Id: netdev.vger.kernel.org From: Donatas Abraitis Date: Thu, 27 Apr 2017 10:12:02 +0300 > RFC4291 2.7 Routers must not forward any multicast packets > beyond of the scope indicated by the scop field in the > destination multicast address. > > Signed-off-by: Donatas Abraitis I think it's a ">=" test which is needed here, not pure equality. Scopes are subsets of other scopes and are therefore allowed within eachother. Did you actually see misbehavior due to this issue, or see a real bonafide conformance test fail? If you're just reading the RFC and sticking tests here and there based upon what you read, without any testing or real life verification of the issue, this is _strongly_ discouraged. It would even be ok if you merely showed how another open source networking stack makes this test.