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From:   Paul Moore <paul@paul-moore.com>
Date:   Mon, 26 Sep 2022 18:41:21 -0400
Message-ID: <CAHC9VhS9kJ4aEp_Y_imcsj_0JOn523Au=ct6uQEPjNDVVjYxVg@mail.gmail.com>
Subject: Re: [PATCH v2 2/2] powerpc/rtas: block error injection when locked down
To:     Nathan Lynch <nathanl@linux.ibm.com>
Cc:     linuxppc-dev@lists.ozlabs.org,
        linux-security-module@vger.kernel.org,
        linux-kernel@vger.kernel.org, jmorris@namei.org,
        mpe@ellerman.id.au, serge@hallyn.com, ajd@linux.ibm.com,
        gcwilson@linux.ibm.com, nayna@linux.ibm.com
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On Mon, Sep 26, 2022 at 9:18 AM Nathan Lynch <nathanl@linux.ibm.com> wrote:
>
> The error injection facility on pseries VMs allows corruption of
> arbitrary guest memory, potentially enabling a sufficiently privileged
> user to disable lockdown or perform other modifications of the running
> kernel via the rtas syscall.
>
> Block the PAPR error injection facility from being opened or called
> when locked down.
>
> Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com>
> ---
>  arch/powerpc/kernel/rtas.c | 25 ++++++++++++++++++++++++-
>  include/linux/security.h   |  1 +
>  security/security.c        |  1 +
>  3 files changed, 26 insertions(+), 1 deletion(-)

The lockdown changes are trivial, but they look fine to me.

Acked-by: Paul Moore <paul@paul-moore.com> (LSM)

-- 
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