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Date: Tue, 17 Jan 2012 13:52:27 -0500 (EST)
Message-Id: <20120117.135227.1766844710849171296.davem@davemloft.net>
To: joe@perches.com
Cc: mirq-linux@rere.qmqm.pl, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] vsprintf: Prevent NULL dereference using %pNF
From: David Miller <davem@davemloft.net>
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From: Joe Perches <joe@perches.com>
Date: Tue, 17 Jan 2012 10:51:13 -0800

> On Tue, 2012-01-17 at 13:46 -0500, David Miller wrote:
>> From: Joe Perches <joe@perches.com>
>> Date: Tue, 17 Jan 2012 10:37:13 -0800
>> > Passing NULL to %pNF is done in skb_gso_segment
>> > which could be dereferenced.
>> skb_gso_segment() should be fixed instead.
> 
> Maybe.  Dereferencing NULL is bad form.

We don't check for NULL for IPV4 or IPV6 addresses, no reason
to treat this any differently.

Either do it for all %pX things, or none of them.