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Date: Thu, 7 Oct 2010 02:21:36 +0100
From: Al Viro <viro@ZenIV.linux.org.uk>
To: Kees Cook <kees.cook@canonical.com>
Cc: linux-kernel@vger.kernel.org, Andrew Morton <akpm@linux-foundation.org>,
        Jiri Slaby <jslaby@suse.cz>, "David S. Miller" <davem@davemloft.net>,
        stable@kernel.org
Subject: Re: [PATCH] ipc: initialize structure memory to zero for shmctl
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References: <20101007001031.GX14666@outflux.net>
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On Wed, Oct 06, 2010 at 05:10:31PM -0700, Kees Cook wrote:
> The old shm interface will leak a few bytes of stack contents. Explicitly
> initialize the structure to zero-fill the untouched fields.

Umm...  I wonder if we ever have gaps in there; note that gaps between
the fields are _not_ initialized in compound literals.  Yes, I realize
that it's a separate problem, but explicit memset() prior to initializations
of fields might be a better solution, covering both.