From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [PATCH v5] ipv6:introduce function to find route for redirect Date: Thu, 05 Sep 2013 12:45:51 -0400 (EDT) Message-ID: <20130905.124551.1242334240830454476.davem@davemloft.net> References: <52271D15.1000806@cn.fujitsu.com> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, hannes@stressinduktion.org To: duanj.fnst@cn.fujitsu.com Return-path: Received: from shards.monkeyblade.net ([149.20.54.216]:33960 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752668Ab3IEQpx (ORCPT ); Thu, 5 Sep 2013 12:45:53 -0400 In-Reply-To: <52271D15.1000806@cn.fujitsu.com> Sender: netdev-owner@vger.kernel.org List-ID: From: Duan Jiong Date: Wed, 04 Sep 2013 19:44:21 +0800 > From: Duan Jiong > > RFC 4861 says that the IP source address of the Redirect is the > same as the current first-hop router for the specified ICMP > Destination Address, so the gateway should be taken into > consideration when we find the route for redirect. > > There was once a check in commit > a6279458c534d01ccc39498aba61c93083ee0372 ("NDISC: Search over > all possible rules on receipt of redirect.") and the check > went away in commit b94f1c0904da9b8bf031667afc48080ba7c3e8c9 > ("ipv6: Use icmpv6_notify() to propagate redirect, instead of > rt6_redirect()"). > > The bug is only "exploitable" on layer-2 because the source > address of the redirect is checked to be a valid link-local > address but it makes spoofing a lot easier in the same L2 > domain nonetheless. > > Thanks very much for Hannes's help. > > Signed-off-by: Duan Jiong Applied.