In changelink ops, the ip6gre_net pointer is retrieved from dev_net(dev), which is wrong in case of x-netns. Thus, the tunnel is not unlinked from its current list and is relinked into another net namespace. This corrupts the tunnel lists and can later trigger a kernel oops.
Fix this by retrieving the netns from device private area. Fixes: c8632fc30bb0 ("net: ip6_gre: Split up ip6gre_changelink()") Cc: Petr Machata <pe...@mellanox.com> Signed-off-by: Olivier Matz <olivier.m...@6wind.com> Acked-by: Nicolas Dichtel <nicolas.dich...@6wind.com> --- net/ipv6/ip6_gre.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/net/ipv6/ip6_gre.c b/net/ipv6/ip6_gre.c index 09d0826742f8..f2543df50035 100644 --- a/net/ipv6/ip6_gre.c +++ b/net/ipv6/ip6_gre.c @@ -2025,9 +2025,9 @@ static int ip6gre_changelink(struct net_device *dev, struct nlattr *tb[], struct nlattr *data[], struct netlink_ext_ack *extack) { - struct ip6gre_net *ign = net_generic(dev_net(dev), ip6gre_net_id); + struct ip6_tnl *t = netdev_priv(dev); + struct ip6gre_net *ign = net_generic(t->net, ip6gre_net_id); struct __ip6_tnl_parm p; - struct ip6_tnl *t; t = ip6gre_changelink_common(dev, tb, data, &p, extack); if (IS_ERR(t)) -- 2.11.0