From mboxrd@z Thu Jan  1 00:00:00 1970
From: Cong Wang <xiyou.wangcong@gmail.com>
Subject: Re: [Patch net] net_sched: refetch skb protocol for each filter
Date: Mon, 14 Jan 2019 11:55:49 -0800
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Cc: Linux Kernel Network Developers <netdev@vger.kernel.org>,
        Martin Olsson <martin.olsson+netdev@sentorsecurity.com>,
        Jamal Hadi Salim <jhs@mojatatu.com>,
        Jiri Pirko <jiri@resnulli.us>
To: Daniel Borkmann <daniel@iogearbox.net>
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On Mon, Jan 14, 2019 at 1:23 AM Daniel Borkmann <daniel@iogearbox.net> wrote:
> Can't we do something like the below instead? Otherwise we'll needlessly refetch
> protocol every time there is a mismatch in above tp->protocol check as well.

Does this save anything given the fact we simply return if err>=0?

The protocol must be fetched, either before the loop or inside the loop, before
this "if err>=0". If we return, it won't be refetched even with my
patch. If we don't,
it has to be refetched again. So, I don't see any difference here.