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From: Dave Hansen <dave.hansen@intel.com>
Message-ID: <56798851.60906@intel.com>
Date: Tue, 22 Dec 2015 09:28:49 -0800
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Subject: Re: [kernel-hardening] [RFC][PATCH 6/7] mm: Add Kconfig option for
 slab sanitization
To: Christoph Lameter <cl@linux.com>
Cc: kernel-hardening@lists.openwall.com, Pekka Enberg <penberg@kernel.org>, David Rientjes <rientjes@google.com>, Joonsoo Kim <iamjoonsoo.kim@lge.com>, Andrew Morton <akpm@linux-foundation.org>, Laura Abbott <laura@labbott.name>, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Kees Cook <keescook@chromium.org>
List-ID: <kernel-hardening.lists.openwall.com>

On 12/22/2015 09:24 AM, Christoph Lameter wrote:
> On Tue, 22 Dec 2015, Dave Hansen wrote:
>> Or are you just saying that we should use the poisoning *code* that we
>> already have in slub?  Using the _code_ looks like a really good idea,
>> whether we're using it to write POISON_FREE, or 0's.  Something like the
>> attached patch?
> 
> Why would you use zeros? The point is just to clear the information right?
> The regular poisoning does that.

It then allows you to avoid the zeroing at allocation time.