From mboxrd@z Thu Jan  1 00:00:00 1970
From: Paolo Bonzini <pbonzini@redhat.com>
Subject: Re: [PATCH] x86: Lock down MSR writing in secure boot
Date: Wed, 13 Feb 2013 20:55:25 +0100
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To: "H. Peter Anvin" <hpa@zytor.com>
Cc: Matthew Garrett <matthew.garrett@nebula.com>, Borislav Petkov <bp@alien8.de>, Kees Cook <keescook@chromium.org>, LKML <linux-kernel@vger.kernel.org>, Thomas Gleixner <tglx@linutronix.de>, Ingo Molnar <mingo@redhat.com>, "x86@kernel.org" <x86@kernel.org>, "linux-efi@vger.kernel.org" <linux-efi@vger.kernel.org>, linux-security-module <linux-security-module@vger.kernel.org>
List-Id: linux-efi@vger.kernel.org

Il 13/02/2013 18:22, H. Peter Anvin ha scritto:
>>
>> On non-x86 machines CAP_SYS_RAWIO is much less dangerous, especially
>> when coupled with file DAC.

Discretionary Access Control.

> Either way, I think you are at best deluded and more like you just
> completely wrong about CAP_SYS_RAWIO being "less dangerous on non-x86
> machines".  With the possible exception of s390 I suspect it is, in
> fact, more dangerous.

I may well be wrong, but as a quick data point CAP_SYS_RAWIO has no
occurrences in arch/ except arch/x86.  Of course a lot of driver
functionality will be limited to CAP_SYS_RAWIO, but usually this
requires having a file descriptor for some file.

Paolo