Re: [PATCH v2 1/1] Add Trusted Path Execution as a stackable LSM

From: Kees Cook
Date: Fri Jun 09 2017 - 08:56:12 EST


On Fri, Jun 9, 2017 at 3:18 AM, Mimi Zohar <zohar@xxxxxxxxxxxxxxxxxx> wrote:
> On Thu, 2017-06-08 at 23:50 -0400, Matt Brown wrote:
>> >>
>> >> * Issues:
>> >> * Can be bypassed by interpreted languages such as python. You can run
>> >> malicious code by doing: python -c 'evil code'
>> >
>> > What's the recommendation for people interested in using TPE but
>> > having interpreters installed?
>> >
>>
>> If you don't need a given interpreter installed, uninstall it. While
>> this is common sense system hardening it especially would make a
>> difference under the TPE threat model.
>>
>> I don't have a knock down answer for this. Interpreters are a hard
>> problem for TPE.
>
> You might be interested in the minor LSM named "shebang", that I
> posted as a proof of concept back in January, which restricts the
> python interactive prompt/interpreter, but allows the scripts
> themselves to be executed.

https://patchwork.kernel.org/patch/9547405/

Maybe these could be merged and the interpreter string could be made
into a configurable list?

-Kees

--
Kees Cook
Pixel Security