[PATCH AUTOSEL 6.10 083/121] fou: remove warn in gue_gro_receive on unsupported protocol

From: Sasha Levin
Date: Wed Jul 31 2024 - 20:35:04 EST


From: Willem de Bruijn <willemb@xxxxxxxxxx>

[ Upstream commit dd89a81d850fa9a65f67b4527c0e420d15bf836c ]

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@xxxxxxxxxx>
Reviewed-by: Eric Dumazet <edumazet@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20240614122552.1649044-1-willemdebruijn.kernel@xxxxxxxxx
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
net/ipv4/fou_core.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/ipv4/fou_core.c b/net/ipv4/fou_core.c
index a8494f796dca3..0abbc413e0fe5 100644
--- a/net/ipv4/fou_core.c
+++ b/net/ipv4/fou_core.c
@@ -433,7 +433,7 @@ static struct sk_buff *gue_gro_receive(struct sock *sk,

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);
--
2.43.0