From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [PATCH net] ipv6: bump genid when the IFA_F_TENTATIVE flag is clear Date: Thu, 24 Nov 2016 12:04:55 -0500 (EST) Message-ID: <20161124.120455.1449935896058022891.davem@davemloft.net> References: Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, hideaki.yoshifuji@miraclelinux.com, hannes@stressinduktion.org To: pabeni@redhat.com Return-path: Received: from shards.monkeyblade.net ([184.105.139.130]:35400 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756858AbcKXRE6 (ORCPT ); Thu, 24 Nov 2016 12:04:58 -0500 In-Reply-To: Sender: netdev-owner@vger.kernel.org List-ID: From: Paolo Abeni Date: Tue, 22 Nov 2016 16:57:40 +0100 > When an ipv6 address has the tentative flag set, it can't be > used as source for egress traffic, while the associated route, > if any, can be looked up and even stored into some dst_cache. > > In the latter scenario, the source ipv6 address selected and > stored in the cache is most probably wrong (e.g. with > link-local scope) and the entity using the dst_cache will > experience lack of ipv6 connectivity until said cache is > cleared or invalidated. > > Overall this may cause lack of connectivity over most IPv6 tunnels > (comprising geneve and vxlan), if the first egress packet reaches > the tunnel before the DaD is completed for the used ipv6 > address. > > This patch bumps a new genid after that the IFA_F_TENTATIVE flag > is cleared, so that dst_cache will be invalidated on > next lookup and ipv6 connectivity restored. > > Fixes: 0c1d70af924b ("net: use dst_cache for vxlan device") > Fixes: 468dfffcd762 ("geneve: add dst caching support") > Acked-by: Hannes Frederic Sowa > Signed-off-by: Paolo Abeni Applied and queued up for -stable, thanks.