From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [PATCH] net: check the length of the data before dereferencing
 it
Date: Mon, 02 Apr 2012 05:59:14 +0200
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To: David Miller <davem@davemloft.net>
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On Sun, 2012-04-01 at 23:57 -0400, David Miller wrote:
> From: Eric Dumazet <eric.dumazet@gmail.com>
> Date: Mon, 02 Apr 2012 05:53:17 +0200
> 
> > On Mon, 2012-04-02 at 11:45 +0800, Changli Gao wrote:
> > 
> >> Thinking about a malformed tcp segment, which has no data but silly
> >> options, and whose last byte is neither TCPOPT_EOL or TCPOPT_NOP, we
> >> will try to dereference one byte over the boundary when parsing the
> >> options. I know we have skb_shared_info at the end and it won't cause
> >> any crash, but should we rely on this fact?
> >> 
> > 
> > No we cant rely on this, kmemcheck might barf on us.
> 
> Give me a break.

Sure. End of discussion.