Subject: Re: [PATCH v2 1/1] Add Trusted Path Execution as a stackable LSM
From: Mimi Zohar <zohar@linux.vnet.ibm.com>
To: Matt Brown <matt@nmatt.com>, Kees Cook <keescook@chromium.org>
Cc: James Morris <james.l.morris@oracle.com>,
        "Serge E. Hallyn" <serge@hallyn.com>,
        LKML <linux-kernel@vger.kernel.org>,
        linux-security-module <linux-security-module@vger.kernel.org>,
        "kernel-hardening@lists.openwall.com" 
        <kernel-hardening@lists.openwall.com>
Date: Fri, 09 Jun 2017 06:18:27 -0400
In-Reply-To: <94ba5ebb-952b-2037-799e-07306629a6f9@nmatt.com>
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         <20170608034349.31876-2-matt@nmatt.com>
         <CAGXu5jLsrTZV_xDR_MPZdkT44P1MpbDiF3Kk2HNWBXKsdY+fzg@mail.gmail.com>
         <94ba5ebb-952b-2037-799e-07306629a6f9@nmatt.com>
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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.

Mimi