linux-kernel - Re: [PATCH 1/2] mm: Expand CONFIG_SLAB_FREELIST

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <202006181330.2FDF47E03D@keescook>
Date:   Thu, 18 Jun 2020 13:37:24 -0700
From:   Kees Cook <keescook@...omium.org>
To:     Matthew Wilcox <willy@...radead.org>
Cc:     Andrew Morton <akpm@...ux-foundation.org>,
        Vlastimil Babka <vbabka@...e.cz>, Roman Gushchin <guro@...com>,
        Christoph Lameter <cl@...ux.com>,
        Alexander Popov <alex.popov@...ux.com>,
        Pekka Enberg <penberg@...nel.org>,
        David Rientjes <rientjes@...gle.com>,
        Joonsoo Kim <iamjoonsoo.kim@....com>, vinmenon@...eaurora.org,
        Matthew Garrett <mjg59@...gle.com>,
        Jann Horn <jannh@...gle.com>,
        Vijayanand Jitta <vjitta@...eaurora.org>, linux-mm@...ck.org,
        linux-kernel@...r.kernel.org
Subject: Re: [PATCH 1/2] mm: Expand CONFIG_SLAB_FREELIST_HARDENED to include
 SLAB and SLOB

On Wed, Jun 17, 2020 at 01:01:51PM -0700, Matthew Wilcox wrote:
> On Wed, Jun 17, 2020 at 12:53:48PM -0700, Kees Cook wrote:
> > Include SLAB and SLOB caches when performing kmem_cache pointer
> 
> ... SLOB?  Really?  Objects from different kmem caches are mixed together
> on the same page with SLOB (at least last time I looked).  So how does
> this work?

Hmm. I'm not sure. I can't even boot a SLOB kernel these days (even
without these patches). But, pages are shared between kmem caches on
SLOB, then I certainly can't add this check for it. :) I'll adjust this
patch.

-- 
Kees Cook