| Message ID | 20200327145444.61875-1-w.dauchy@criteo.com |
|---|---|
| State | New |
| Headers | show |
| Series | [v2,net] net, ip_tunnel: fix interface lookup with no key | expand |
diff --git a/net/ipv4/ip_tunnel.c b/net/ipv4/ip_tunnel.c index 74e1d964a615..b30485615426 100644 --- a/net/ipv4/ip_tunnel.c +++ b/net/ipv4/ip_tunnel.c @@ -142,11 +142,8 @@ struct ip_tunnel *ip_tunnel_lookup(struct ip_tunnel_net *itn, 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_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(struct ip_tunnel_net *itn, cand = t; } -skip_key_lookup: if (cand) return cand;
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> --- net/ipv4/ip_tunnel.c | 6 +----- 1 file changed, 1 insertion(+), 5 deletions(-)