| From foo@baz Thu Feb 27 20:11:26 PST 2014 |
| From: Nicolas Dichtel <nicolas.dichtel@6wind.com> |
| Date: Mon, 17 Feb 2014 14:22:21 +0100 |
| Subject: gre: add link local route when local addr is any |
| |
| From: Nicolas Dichtel <nicolas.dichtel@6wind.com> |
| |
| [ Upstream commit 08b44656c08c8c2f73cdac2a058be2880e3361f2 ] |
| |
| 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 <sesse@samfundet.no> |
| Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> |
| Signed-off-by: David S. Miller <davem@davemloft.net> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| --- |
| net/ipv6/addrconf.c | 2 ++ |
| 1 file changed, 2 insertions(+) |
| |
| --- a/net/ipv6/addrconf.c |
| +++ b/net/ipv6/addrconf.c |
| @@ -2726,6 +2726,8 @@ static void addrconf_gre_config(struct n |
| 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 |
| |
