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Date: Tue, 9 Apr 2013 11:23:15 +0200 (CEST)
From: Thomas Gleixner <tglx@linutronix.de>
To: "H. Peter Anvin" <hpa@zytor.com>
cc: Kees Cook <keescook@chromium.org>, Ingo Molnar <mingo@redhat.com>,
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Subject: Re: [PATCH] x86: make IDT read-only
In-Reply-To: <51634935.9010905@zytor.com>
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References: <20130408224328.GA17641@www.outflux.net> <51634935.9010905@zytor.com>
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On Mon, 8 Apr 2013, H. Peter Anvin wrote:

> On 04/08/2013 03:43 PM, Kees Cook wrote:
> > This makes the IDT unconditionally read-only. This primarily removes
> > the IDT from being a target for arbitrary memory write attacks. It has
> > an added benefit of also not leaking (via the "sidt" instruction) the
> > kernel base offset, if it has been relocated.
> > 
> > Signed-off-by: Kees Cook <keescook@chromium.org>
> > Cc: Eric Northup <digitaleric@google.com>
> 
> Also, tglx: does this interfere with your per-cpu IDT efforts?

I don't think so. And it's on the backburner at the moment.

Thanks,

	tglx
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