fou: remove warn in gue_gro_receive on unsupported protocol

Drop the WARN_ON_ONCE inn gue_gro_receive if the encapsulated type is
not known or does not have a GRO handler.

Such a packet is easily constructed. Syzbot generates them and sets
off this warning.

Remove the warning as it is expected and not actionable.

The warning was previously reduced from WARN_ON to WARN_ON_ONCE in
commit 270136613bf7 ("fou: Do WARN_ON_ONCE in gue_gro_receive for bad
proto callbacks").

Signed-off-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20240614122552.1649044-1-willemdebruijn.kernel@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/net/ipv4/fou_core.c b/net/ipv4/fou_core.c
index a8494f796dca336ca4b30fdbc2f91f3a7e6631fb..0abbc413e0fe510d644a81852932c352f7b098ea 100644 (file)
--- a/net/ipv4/fou_core.c
+++ b/net/ipv4/fou_core.c
@@ -433,7 +433,7 @@ next_proto:
 
        offloads = NAPI_GRO_CB(skb)->is_ipv6 ? inet6_offloads : inet_offloads;
        ops = rcu_dereference(offloads[proto]);
-       if (WARN_ON_ONCE(!ops || !ops->callbacks.gro_receive))
+       if (!ops || !ops->callbacks.gro_receive)
                goto out;
 
        pp = call_gro_receive(ops->callbacks.gro_receive, head, skb);