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Date: Sun, 13 Jun 2010 23:57:00 +0200
From: Patrick Lamaiziere <patfbsd@davenulle.org>
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Cc: ticso@cicely.de
Subject: Re: Cleanup for cryptographic algorithms vs. compiler optimizations
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Le Sun, 13 Jun 2010 23:35:12 +0200,
Bernd Walter <ticso@cicely7.cicely.de> a écrit :

> Go back to the originating mail.
> Crypto code wasn't aware of this problem and this is a way more
> obviuous optimization than function exchange.
> And I do believe that the programmers were clever people.
> Alarming, isn't it?

The removal of dead store by gcc is recent.

There was a discussion about this problem on the linux crypto mailing
list, see:
http://www.mail-archive.com/linux-crypto@vger.kernel.org/msg04229.html

If i remember well, they have introduced a secure_memset() function or
something like that, but I do not find this piece of code any more.

Regards.