From: Andi Kleen <ak@suse.de>
To: Mitchell Blank Jr <mitch@sfgoth.com>
Subject: Re: [patch] avoid unaligned access when accessing poll stack
Date: Sat, 1 Apr 2006 04:44:09 +0200
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Cc: Jes Sorensen <jes@sgi.com>, Linus Torvalds <torvalds@osdl.org>,
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       linux-ia64@vger.kernel.org
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On Saturday 01 April 2006 04:35, Mitchell Blank Jr wrote:

>   * I also changed "size" to be unsigned since that makes more sense and
>     is less prone to overflow bugs.  I'm also a little scared by the
>     "kmalloc(6 * size)" since that type of call is a classic multiply-overflow
>     security hole (hence libc's calloc() API).  However "size" is constrained
>     by fdt->max_fdset so I think it isn't exploitable.  The kernel doesn't
>     have an overflow-safe API for kmalloc'ing arrays, does it?

kcalloc. But it's slow since it memsets.

-Andi

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