From mboxrd@z Thu Jan  1 00:00:00 1970
From: Pablo Neira Ayuso <pablo@netfilter.org>
Subject: Re: [PATCH nf 1/1] netfilter: seqadj: Fix possible non-linear data
 access for TCP header
Date: Thu, 13 Apr 2017 23:42:49 +0200
Message-ID: <20170413214249.GA3612@salvia>
References: <1491820563-98023-1-git-send-email-gfree.wind@foxmail.com>
 <20170413213705.GA3430@salvia>
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Cc: netfilter-devel@vger.kernel.org, Gao Feng <fgao@ikuai8.com>
To: gfree.wind@foxmail.com
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On Thu, Apr 13, 2017 at 11:37:05PM +0200, Pablo Neira Ayuso wrote:
> On Mon, Apr 10, 2017 at 06:36:03PM +0800, gfree.wind@foxmail.com wrote:
> > From: Gao Feng <fgao@ikuai8.com>
> > 
> > The current call path of nf_ct_tcp_seqadj_set is the following.
> > 
> > nfqnl_recv_verdict->ctnetlink_glue_hook->ctnetlink_glue_seqadj
> > ->nf_ct_tcp_seqadj_set.
> > 
> > It couldn't make sure the TCP header is in the linear data part.
> > So use the skb_header_pointer instead of the current codes.
> > 
> > BTW, the nf_ct_tcp_seqadj_set is one external function of netfilter
> > which works in the network layer, it should not assume the transport
> > header is in the linear data.
> 
> Applied.
> 
> I wish you fix your mail client setup, it is a mess. I always have to
> figure out which patch is correct in the large bunch.  You have to be
> more careful.

Wait, I'm dropping this.

Caller already guarantee that this area has been skb_make_writable via
payload mangle, right?

Please, have a closer look.