Date: Fri, 18 Nov 2016 12:19:42 -0600 (CST)
From: Christoph Lameter <cl@linux.com>
To: Kees Cook <keescook@chromium.org>
cc: Michael Ellerman <mpe@ellerman.id.au>,
        Andrew Morton <akpm@linux-foundation.org>,
        Pekka Enberg <penberg@kernel.org>,
        David Rientjes <rientjes@google.com>,
        Joonsoo Kim <iamjoonsoo.kim@lge.com>, Linux-MM <linux-mm@kvack.org>,
        LKML <linux-kernel@vger.kernel.org>,
        "kernel-hardening@lists.openwall.com" 
        <kernel-hardening@lists.openwall.com>
Subject: Re: [PATCH v2] slab: Add POISON_POINTER_DELTA to ZERO_SIZE_PTR
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On Fri, 18 Nov 2016, Kees Cook wrote:
> In this case, what about the original < ZERO_SIZE_PTR check Michael
> suggested? At least the one use in usercopy.c needs to be fixed, but
> otherwise, it should be fine?

Looks like it.