linux-kernel - Re: [kernel-hardening] Re: [PATCH v2 02/11] mm: Hardened usercopy

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: <CAGXu5jJC0KGR1Q44MW_Rv_N1yFu8m4b8EQY59J-VhLHj_wt+Uw@mail.gmail.com>
Date:	Fri, 15 Jul 2016 12:23:11 -0700
From:	Kees Cook <keescook@...omium.org>
To:	"kernel-hardening@...ts.openwall.com" 
	<kernel-hardening@...ts.openwall.com>
Cc:	Balbir Singh <bsingharora@...il.com>,
	LKML <linux-kernel@...r.kernel.org>,
	Rik van Riel <riel@...hat.com>,
	Casey Schaufler <casey@...aufler-ca.com>,
	PaX Team <pageexec@...email.hu>,
	Brad Spengler <spender@...ecurity.net>,
	Russell King <linux@...linux.org.uk>,
	Catalin Marinas <catalin.marinas@....com>,
	Will Deacon <will.deacon@....com>,
	Ard Biesheuvel <ard.biesheuvel@...aro.org>,
	Benjamin Herrenschmidt <benh@...nel.crashing.org>,
	Michael Ellerman <mpe@...erman.id.au>,
	Tony Luck <tony.luck@...el.com>,
	Fenghua Yu <fenghua.yu@...el.com>,
	"David S. Miller" <davem@...emloft.net>,
	"x86@...nel.org" <x86@...nel.org>,
	Christoph Lameter <cl@...ux.com>,
	Pekka Enberg <penberg@...nel.org>,
	David Rientjes <rientjes@...gle.com>,
	Joonsoo Kim <iamjoonsoo.kim@....com>,
	Andrew Morton <akpm@...ux-foundation.org>,
	Andy Lutomirski <luto@...nel.org>,
	Borislav Petkov <bp@...e.de>,
	Mathias Krause <minipli@...glemail.com>,
	Jan Kara <jack@...e.cz>, Vitaly Wool <vitalywool@...il.com>,
	Andrea Arcangeli <aarcange@...hat.com>,
	Dmitry Vyukov <dvyukov@...gle.com>,
	Laura Abbott <labbott@...oraproject.org>,
	"linux-arm-kernel@...ts.infradead.org" 
	<linux-arm-kernel@...ts.infradead.org>, linux-ia64@...r.kernel.org,
	"linuxppc-dev@...ts.ozlabs.org" <linuxppc-dev@...ts.ozlabs.org>,
	sparclinux <sparclinux@...r.kernel.org>,
	linux-arch <linux-arch@...r.kernel.org>,
	Linux-MM <linux-mm@...ck.org>
Subject: Re: [kernel-hardening] Re: [PATCH v2 02/11] mm: Hardened usercopy

On Fri, Jul 15, 2016 at 12:19 PM, Daniel Micay <danielmicay@...il.com> wrote:
>> I'd like it to dump stack and be fatal to the process involved, but
>> yeah, I guess BUG() would work. Creating an infrastructure for
>> handling security-related Oopses can be done separately from this
>> (and
>> I'd like to see that added, since it's a nice bit of configurable
>> reactivity to possible attacks).
>
> In grsecurity, the oops handling also uses do_group_exit instead of
> do_exit but both that change (or at least the option to do it) and the
> exploit handling could be done separately from this without actually
> needing special treatment for USERCOPY. Could expose is as something
> like panic_on_oops=2 as a balance between the existing options.

I'm also uncomfortable about BUG() being removed by unsetting
CONFIG_BUG, but that seems unlikely. :)

-Kees

-- 
Kees Cook
Chrome OS & Brillo Security