From mboxrd@z Thu Jan 1 00:00:00 1970 From: Nicolas Dichtel Subject: [PATCH net] gre: add link local route when local addr is any Date: Mon, 17 Feb 2014 14:22:21 +0100 Message-ID: <1392643341-4288-1-git-send-email-nicolas.dichtel@6wind.com> References: <5301E59F.5090506@6wind.com> Cc: hannes@stressinduktion.org, itk-intern@samfundet.no, davem@davemloft.net, netdev@vger.kernel.org, Nicolas Dichtel To: sesse@samfundet.no Return-path: Received: from 33.106-14-84.ripe.coltfrance.com ([84.14.106.33]:33411 "EHLO proxy.6wind.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752702AbaBQNYU (ORCPT ); Mon, 17 Feb 2014 08:24:20 -0500 In-Reply-To: <5301E59F.5090506@6wind.com> Sender: netdev-owner@vger.kernel.org List-ID: This bug was reported by Steinar H. Gunderson and was introduced by commit f7cb8886335d ("sit/gre6: don't try to add the same route two times"). root@morgental:~# ip tunnel add foo mode gre remote 1.2.3.4 ttl 64 root@morgental:~# ip link set foo up mtu 1468 root@morgental:~# ip -6 route show dev foo fe80::/64 proto kernel metric 256 but after the above commit, no such route shows up. There is no link local route because dev->dev_addr is 0 (because local ipv4 address is 0), hence no link local address is configured. In this scenario, the link local address is added manually: 'ip -6 addr add fe80::1 dev foo' and because prefix is /128, no link local route is added by the kernel. Even if the right things to do is to add the link local address with a /64 prefix, we need to restore the previous behavior to avoid breaking userpace. Reported-by: Steinar H. Gunderson Signed-off-by: Nicolas Dichtel --- net/ipv6/addrconf.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c index ad235690684c..fdbfeca36d63 100644 --- a/net/ipv6/addrconf.c +++ b/net/ipv6/addrconf.c @@ -2783,6 +2783,8 @@ static void addrconf_gre_config(struct net_device *dev) ipv6_addr_set(&addr, htonl(0xFE800000), 0, 0, 0); if (!ipv6_generate_eui64(addr.s6_addr + 8, dev)) addrconf_add_linklocal(idev, &addr); + else + addrconf_prefix_route(&addr, 64, dev, 0, 0); } #endif -- 1.8.5.4