net, ip_tunnel: fix interface lookup with no key
[ 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>
diff --git a/net/ipv4/ip_tunnel.c b/net/ipv4/ip_tunnel.c
index 14fd8a3..b37abba 100644
--- a/net/ipv4/ip_tunnel.c
+++ b/net/ipv4/ip_tunnel.c
@@ -155,11 +155,8 @@
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))
@@ -171,7 +168,6 @@
cand = t;
}
-skip_key_lookup:
if (cand)
return cand;