Date: Tue, 18 Apr 2017 08:31:24 -0500 (CDT)
From: Christoph Lameter <cl@linux.com>
To: Michal Hocko <mhocko@kernel.org>
cc: Kees Cook <keescook@chromium.org>,
        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>
Subject: Re: [PATCH] mm: Add additional consistency check
In-Reply-To: <20170418064124.GA22360@dhcp22.suse.cz>
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On Tue, 18 Apr 2017, Michal Hocko wrote:

> > The patch does not do that. See my review. Invalid points to kfree are
> > already caught with a bug on. See kfree in mm/slub.c
>
> Are you even reading those emails? First of all we are talking about
> slab here. Secondly I've already pointed out that the BUG_ON(!PageSlab)
> in kmem_freepages is already too late because we do operate on a
> potential garbage from invalid page...

Again this is confusing because you are discussing something that was not
covered by the patch submitted. Please start another discussion thread
on kfree() separately from the discussion of the patch here.