Re: [PATCH net-next v4 4/4] net: gro: move L3 flush checks to tcp_gro_receive

From: Eric Dumazet
Date: Tue Mar 26 2024 - 10:17:12 EST


On Mon, Mar 25, 2024 at 7:27 PM Richard Gobert <richardbgobert@xxxxxxxxx> wrote:
>
> {inet,ipv6}_gro_receive functions perform flush checks (ttl, flags,
> iph->id, ...) against all packets in a loop. These flush checks are used
> currently only in tcp flows in GRO.

I think this is a bug.

GRO should not aggregate packets if their ttl/tos fields do not match.