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

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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>
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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