From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:40442 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751421AbdGRIHD (ORCPT ); Tue, 18 Jul 2017 04:07:03 -0400 Subject: Patch "ipv6: avoid unregistering inet6_dev for loopback" has been added to the 4.9-stable tree To: xiyou.wangcong@gmail.com, andreyknvl@google.com, davem@davemloft.net, dlezcano@fr.ibm.com, dsahern@gmail.com, gregkh@linuxfoundation.org Cc: , From: Date: Tue, 18 Jul 2017 10:06:52 +0200 Message-ID: <1500365212140125@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: This is a note to let you know that I've just added the patch titled ipv6: avoid unregistering inet6_dev for loopback to the 4.9-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: ipv6-avoid-unregistering-inet6_dev-for-loopback.patch and it can be found in the queue-4.9 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let know about it. >>From 60abc0be96e00ca71bac083215ac91ad2e575096 Mon Sep 17 00:00:00 2001 From: WANG Cong Date: Wed, 21 Jun 2017 14:34:58 -0700 Subject: ipv6: avoid unregistering inet6_dev for loopback From: WANG Cong commit 60abc0be96e00ca71bac083215ac91ad2e575096 upstream. The per netns loopback_dev->ip6_ptr is unregistered and set to NULL when its mtu is set to smaller than IPV6_MIN_MTU, this leads to that we could set rt->rt6i_idev NULL after a rt6_uncached_list_flush_dev() and then crash after another call. In this case we should just bring its inet6_dev down, rather than unregistering it, at least prior to commit 176c39af29bc ("netns: fix addrconf_ifdown kernel panic") we always override the case for loopback. Thanks a lot to Andrey for finding a reliable reproducer. Fixes: 176c39af29bc ("netns: fix addrconf_ifdown kernel panic") Reported-by: Andrey Konovalov Cc: Andrey Konovalov Cc: Daniel Lezcano Cc: David Ahern Signed-off-by: Cong Wang Acked-by: David Ahern Tested-by: Andrey Konovalov Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/ipv6/addrconf.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) --- a/net/ipv6/addrconf.c +++ b/net/ipv6/addrconf.c @@ -3316,6 +3316,7 @@ static int addrconf_notify(struct notifi struct net_device *dev = netdev_notifier_info_to_dev(ptr); struct netdev_notifier_changeupper_info *info; struct inet6_dev *idev = __in6_dev_get(dev); + struct net *net = dev_net(dev); int run_pending = 0; int err; @@ -3331,7 +3332,7 @@ static int addrconf_notify(struct notifi case NETDEV_CHANGEMTU: /* if MTU under IPV6_MIN_MTU stop IPv6 on this interface. */ if (dev->mtu < IPV6_MIN_MTU) { - addrconf_ifdown(dev, 1); + addrconf_ifdown(dev, dev != net->loopback_dev); break; } @@ -3447,7 +3448,7 @@ static int addrconf_notify(struct notifi * IPV6_MIN_MTU stop IPv6 on this interface. */ if (dev->mtu < IPV6_MIN_MTU) - addrconf_ifdown(dev, 1); + addrconf_ifdown(dev, dev != net->loopback_dev); } break; Patches currently in stable-queue which might be from xiyou.wangcong@gmail.com are queue-4.9/ipv6-avoid-unregistering-inet6_dev-for-loopback.patch queue-4.9/tcp-reset-sk_rx_dst-in-tcp_disconnect.patch