From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [PATCH net-next 0/4] vxlan: fix default fdb entry user-space notify ordering/race Date: Sat, 07 Jul 2018 20:23:04 +0900 (KST) Message-ID: <20180707.202304.545097069909614694.davem@davemloft.net> References: <1530747992-15878-1-git-send-email-roopa@cumulusnetworks.com> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, jbenc@redhat.com, mike.rapoport@ravellosystems.com, stephen@networkplumber.org To: roopa@cumulusnetworks.com Return-path: Received: from shards.monkeyblade.net ([23.128.96.9]:51620 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753730AbeGGLXH (ORCPT ); Sat, 7 Jul 2018 07:23:07 -0400 In-Reply-To: <1530747992-15878-1-git-send-email-roopa@cumulusnetworks.com> Sender: netdev-owner@vger.kernel.org List-ID: From: Roopa Prabhu Date: Wed, 4 Jul 2018 16:46:28 -0700 > From: Roopa Prabhu > > Problem: > In vxlan_newlink, a default fdb entry is added before register_netdev. > The default fdb creation function notifies user-space of the > fdb entry on the vxlan device which user-space does not know about yet. > (RTM_NEWNEIGH goes before RTM_NEWLINK for the same ifindex). > > This series fixes the user-space netlink notification ordering issue > with the following changes: > - decouple fdb notify from fdb create. > - Move fdb notify after register_netdev. > - modify rtnl_configure_link to allow configuring a link early. > - Call rtnl_configure_link in vxlan newlink handler to notify > userspace about the newlink before fdb notify and > hence avoiding the user-space race. > > Fixes: afbd8bae9c79 ("vxlan: add implicit fdb entry for default destination") > Signed-off-by: Roopa Prabhu This is quite an old bug (circa v3.11). Maybe after this cooks for some time in net-next you can also submit it for 'net' and we can thus send it off to -stable as well? Applied to net-next, thanks.