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Date:   Thu, 23 Jan 2020 15:29:29 +0100
From:   Florian Westphal <fw@strlen.de>
To:     Daniel Borkmann <daniel@iogearbox.net>
Cc:     Florian Westphal <fw@strlen.de>,
        Praveen Chaudhary <praveen5582@gmail.com>, pablo@netfilter.org,
        davem@davemloft.net, kadlec@netfilter.org,
        netfilter-devel@vger.kernel.org, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org, Zhenggen Xu <zxu@linkedin.com>,
        Andy Stracner <astracner@linkedin.com>
Subject: Re: [PATCH v3] [net]: Fix skb->csum update in
 inet_proto_csum_replace16().
Message-ID: <20200123142929.GV795@breakpoint.cc>
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Daniel Borkmann <daniel@iogearbox.net> wrote:
> On 1/23/20 9:21 AM, Florian Westphal wrote:
> > So, AFAIU from what you're saying above the patch seems fine as-is and
> > just needs a more verbose commit message explaining why replace16()
> > doesn't update skb->csum while all the other ones do.
> > 
> > Is that correct?
> 
> Probably better a comment in the code to avoid confusion on why it's not done in
> inet_proto_csum_replace16() but all the other cases; mainly to avoid some folks
> in future sending random cleanup patches w/ removal attempts.

Makes sense, thanks!

Praveen, can you spin a v4 with a comment in replace16 that it
intentionally elides the skb->csum update because the function is
only used by ipv6?

Thanks!