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Date: Mon, 16 Feb 2009 21:58:14 +0200
From: Pekka Enberg <penberg@cs.helsinki.fi>
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To: Andrew Morton <akpm@linux-foundation.org>
CC: Johannes Weiner <hannes@cmpxchg.org>, linux-mm@kvack.org,
       linux-kernel@vger.kernel.org
Subject: Re: [patch 0/8] kzfree()
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Hi Andrew,

Andrew Morton wrote:
> On Mon, 16 Feb 2009 15:29:26 +0100 Johannes Weiner <hannes@cmpxchg.org> wrote:
> 
>> This series introduces kzfree() and converts callsites which do
>> memset() + kfree() explicitely.
> 
> I dunno, this looks like putting lipstick on a pig.
> 
> What is the point in zeroing memory just before freeing it?  afacit
> this is always done as a poor-man's poisoning operation.

I think they do it as security paranoia to make sure other callers don't 
accidentally see parts of crypto keys, passwords, and such. So I don't 
think we can just get rid of the memsets.

			Pekka