Re:

Kees Cook
2013-09-04T15:53:38Z

On Tue, Sep 3, 2013 at 4:50 PM, Matthew Garrett
<matthew.garrett@nebula.com> wrote:
> We have two in-kernel mechanisms for restricting module loading - disabling
> it entirely, or limiting it to the loading of modules signed with a trusted
> key. These can both be configured in such a way that even root is unable to
> relax the restrictions.
>
> However, right now, there's several other straightforward ways for root to
> modify running kernel code. At the most basic level these allow root to
> reset the configuration such that modules can be loaded again, rendering
> the existing restrictions useless.
>
> This patchset adds additional restrictions to various kernel entry points
> that would otherwise make it straightforward for root to disable enforcement
> of module loading restrictions. It also provides a patch that allows the
> kernel to be configured such that module signing will be automatically
> enabled when the system is booting via UEFI Secure Boot, allowing a stronger
> guarantee of kernel integrity.
>
> V3 addresses some review feedback and also locks down uswsusp.

Looks good to me. Consider the entire series:

Acked-by: Kees Cook <keescook@chromium.org>

-Kees

--
Kees Cook
Chrome OS Security