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Date: Wed, 12 Dec 2012 16:43:21 -0800
From: Andrew Morton <akpm@linux-foundation.org>
To: Stephan Mueller <smueller@chronox.de>
Cc: "Ted Ts'o" <tytso@mit.edu>, lkml <linux-kernel@vger.kernel.org>,
        Jeff Liu <jeff.liu@oracle.com>, Kees Cook <keescook@chromium.org>
Subject: Re: [PATCH] avoid entropy starvation due to stack protection
Message-Id: <20121212164321.a01c5641.akpm@linux-foundation.org>
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On Tue, 11 Dec 2012 13:33:04 +0100
Stephan Mueller <smueller@chronox.de> wrote:

> Some time ago, I noticed the fact that for every newly
> executed process, the function create_elf_tables requests 16 bytes of
> randomness from get_random_bytes. This is easily visible when calling
> 
> while [ 1 ]
> do
> 	cat /proc/sys/kernel/random/entropy_avail
> 	sleep 1
> done

Please see
http://ozlabs.org/~akpm/mmotm/broken-out/binfmt_elfc-use-get_random_int-to-fix-entropy-depleting.patch

That patch is about one week from a mainline merge, btw.