From mboxrd@z Thu Jan  1 00:00:00 1970
From: Shmulik Ladkani <shmulik.ladkani@ravellosystems.com>
Subject: Re: [PATCH v2 net] net: skbuff: skb_vlan_push: Fix wrong unwinding
 of skb->data after __vlan_insert_tag call
Date: Wed, 28 Sep 2016 20:11:36 +0300
Message-ID: <20160928201136.1600ac65@halley>
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Cc: "David S. Miller" <davem@davemloft.net>,
        Pravin Shelar <pshelar@ovn.org>, netdev@vger.kernel.org,
        Shmulik Ladkani <shmulik.ladkani@gmail.com>,
        Jiri Pirko <jiri@mellanox.com>
To: Daniel Borkmann <daniel@iogearbox.net>
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On Wed, 28 Sep 2016 16:43:38 +0200 Daniel Borkmann <daniel@iogearbox.net> wrote:
> > (1) suppose upon entry we have
> >
> >      DA,SA,0x8100,TCI,0x0800,
> >      ^                ^
> >      mac_hdr          data
> >
> > initial offset is 18, and after current unwinding code we'll get  
> 
> You mean data points after the 0x0800, right?

Sorry. Yes, exactly as you say. Initially 18 bytes ahead:

    DA,SA,0x8100,TCI,0x0800,
    ^                       ^
    mac_hdr                 data