[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date: Thu, 7 Jul 2016 13:25:21 -0400
From: Kees Cook <keescook@...omium.org>
To: Baruch Siach <baruch@...s.co.il>
Cc: LKML <linux-kernel@...r.kernel.org>, Jan Kara <jack@...e.cz>,
"kernel-hardening@...ts.openwall.com"
<kernel-hardening@...ts.openwall.com>,
Catalin Marinas <catalin.marinas@....com>,
Will Deacon <will.deacon@....com>,
Linux-MM <linux-mm@...ck.org>,
sparclinux <sparclinux@...r.kernel.org>,
linux-ia64@...r.kernel.org, Christoph Lameter <cl@...ux.com>,
Andrea Arcangeli <aarcange@...hat.com>,
linux-arch <linux-arch@...r.kernel.org>,
Michael Ellerman <mpe@...erman.id.au>,
"x86@...nel.org" <x86@...nel.org>,
Russell King <linux@...linux.org.uk>,
"linux-arm-kernel@...ts.infradead.org"
<linux-arm-kernel@...ts.infradead.org>,
Benjamin Herrenschmidt <benh@...nel.crashing.org>,
PaX Team <pageexec@...email.hu>, Borislav Petkov <bp@...e.de>,
Mathias Krause <minipli@...glemail.com>,
Fenghua Yu <fenghua.yu@...el.com>,
Rik van Riel <riel@...hat.com>,
Vitaly Wool <vitalywool@...il.com>,
David Rientjes <rientjes@...gle.com>,
Tony Luck <tony.luck@...el.com>,
Andy Lutomirski <luto@...nel.org>,
Joonsoo Kim <iamjoonsoo.kim@....com>,
Dmitry Vyukov <dvyukov@...gle.com>,
Laura Abbott <labbott@...oraproject.org>,
Brad Spengler <spender@...ecurity.net>,
Ard Biesheuvel <ard.biesheuvel@...aro.org>,
Pekka Enberg <penberg@...nel.org>,
Casey Schaufler <casey@...aufler-ca.com>,
Andrew Morton <akpm@...ux-foundation.org>,
"linuxppc-dev@...ts.ozlabs.org" <linuxppc-dev@...ts.ozlabs.org>,
"David S. Miller" <davem@...emloft.net>
Subject: Re: [PATCH 1/9] mm: Hardened usercopy
On Thu, Jul 7, 2016 at 1:37 AM, Baruch Siach <baruch@...s.co.il> wrote:
> Hi Kees,
>
> On Wed, Jul 06, 2016 at 03:25:20PM -0700, Kees Cook wrote:
>> +#ifdef CONFIG_HAVE_HARDENED_USERCOPY_ALLOCATOR
>
> Should be CONFIG_HARDENED_USERCOPY to match the slab/slub implementation
> condition.
>
>> +const char *__check_heap_object(const void *ptr, unsigned long n,
>> + struct page *page);
>> +#else
>> +static inline const char *__check_heap_object(const void *ptr,
>> + unsigned long n,
>> + struct page *page)
>> +{
>> + return NULL;
>> +}
>> +#endif
Hmm, I think what I have is correct: if the allocator supports the
heap object checking, it defines __check_heap_object as existing via
CONFIG_HAVE_HARDENED_USERCOPY_ALLOCATOR. If usercopy checking is done
at all is controlled by CONFIG_HARDENED_USERCOPY.
I.e. you can have the other usercopy checks even if your allocator
doesn't support object size checking.
-Kees
--
Kees Cook
Chrome OS & Brillo Security
Powered by blists - more mailing lists