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Date: Sun, 10 Feb 2013 15:50:57 -0800
From: Greg KH <gregkh@linuxfoundation.org>
To: Daniel Borkmann <dborkman@redhat.com>
Cc: Joe Perches <joe@perches.com>, akpm@linux-foundation.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] lib: memcmp_nta: add timing-attack secure memcmp
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On Mon, Feb 11, 2013 at 12:30:51AM +0100, Daniel Borkmann wrote:
> On 02/11/2013 12:24 AM, Joe Perches wrote:
> >On Sun, 2013-02-10 at 23:00 +0100, Daniel Borkmann wrote:
> >>add memcmp_nta ({n}o {t}iming {a}ttacks)
> >
> >Why should this be in the kernel?
> 
> As the commit message already says, so that current or future (e.g.) network
> protocol code or modules can make use of this when dealing with cryptographic
> hash comparisons.

Do we have any in-kernel users that need this?  If not, then don't add
it now, but rather, add it when we actually have a user.  We almost
never add kernel functions that no one calls, that would be just
wasteful.

sorry,

greg k-h