From mboxrd@z Thu Jan  1 00:00:00 1970
From: Daniel Borkmann <daniel@iogearbox.net>
Subject: Re: [PATCH net-next 1/1] net_sched: Introduce skbmod action
Date: Tue, 19 Jul 2016 17:03:40 +0200
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Cc: davem@davemloft.net, netdev@vger.kernel.org,
	xiyou.wangcong@gmail.com, nikolay@cumulusnetworks.com
To: Jamal Hadi Salim <jhs@mojatatu.com>,
	Alexei Starovoitov <alexei.starovoitov@gmail.com>
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On 07/19/2016 03:56 PM, Jamal Hadi Salim wrote:
[...]
>> But apart from this,
>> neither pedit nor tcf_skbmod_run() here handle checksum complete, so you'll
>> potentially get false positives wrt csum corruption and drops as a result
>> when using either of the two.
>
> pedit maybe tricky. Any suggestions?
> On tcf_skbmod_run, mostly ignorance: while doing only ethernet updates;
> is it still needed to do the checksum complete?

Well, what Cong recently fixed with mirred was related to mac header ...

You probably need skb_postpull_rcsum(), skb_postpush_rcsum() pair.

Also, what about skb_try_make_writable()?