From: William Dauchy w.dauchy@criteo.com
[ Upstream commit 25629fdaff2ff509dd0b3f5ff93d70a75e79e0a1 ]
when creating a new ipip interface with no local/remote configuration, the lookup is done with TUNNEL_NO_KEY flag, making it impossible to match the new interface (only possible match being fallback or metada case interface); e.g: `ip link add tunl1 type ipip dev eth0`
To fix this case, adding a flag check before the key comparison so we permit to match an interface with no local/remote config; it also avoids breaking possible userland tools relying on TUNNEL_NO_KEY flag and uninitialised key.
context being on my side, I'm creating an extra ipip interface attached to the physical one, and moving it to a dedicated namespace.
Fixes: c54419321455 ("GRE: Refactor GRE tunneling code.") Signed-off-by: William Dauchy w.dauchy@criteo.com 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/ipv4/ip_tunnel.c | 6 +----- 1 file changed, 1 insertion(+), 5 deletions(-)
--- a/net/ipv4/ip_tunnel.c +++ b/net/ipv4/ip_tunnel.c @@ -142,11 +142,8 @@ struct ip_tunnel *ip_tunnel_lookup(struc cand = t; }
- if (flags & TUNNEL_NO_KEY) - goto skip_key_lookup; - hlist_for_each_entry_rcu(t, head, hash_node) { - if (t->parms.i_key != key || + if ((!(flags & TUNNEL_NO_KEY) && t->parms.i_key != key) || t->parms.iph.saddr != 0 || t->parms.iph.daddr != 0 || !(t->dev->flags & IFF_UP)) @@ -158,7 +155,6 @@ struct ip_tunnel *ip_tunnel_lookup(struc cand = t; }
-skip_key_lookup: if (cand) return cand;