From: Paolo Abeni <pab...@redhat.com>
Date: Tue, 18 Jul 2017 11:57:55 +0200
> Eric noticed that in udp_recvmsg() we still need to access
> skb->dst while processing the IP options.
> Since commit 0a463c78d25b ("udp: avoid a cache miss on dequeue")
> skb->dst is no more available at recvmsg() time and bad things
> will happen if we enter the relevant code path.
>
> This commit address the issue, avoid clearing skb->dst if
> any IP options are present into the relevant skb.
> Since the IP CB is contained in the first skb cacheline, we can
> test it to decide to leverage the consume_stateless_skb()
> optimization, without measurable additional cost in the faster
> path.
>
> v1 -> v2: updated commit message tags
>
> Fixes: 0a463c78d25b ("udp: avoid a cache miss on dequeue")
> Reported-by: Andrey Konovalov <andreyk...@google.com>
> Reported-by: Eric Dumazet <eduma...@google.com>
> Signed-off-by: Paolo Abeni <pab...@redhat.com>
Applied, thank you.
