From: Tycho Andersen <tycho-E0fblnxP3wo@public.gmane.org>
Subject: Re: [RFC PATCH v9 03/13] mm: Add support for eXclusive Page Frame
	Ownership (XPFO)
Date: Wed, 17 Apr 2019 13:52:13 -0600
Message-ID: <20190417195213.GE3758@cisco>
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To: Andy Lutomirski <luto-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
Cc: Dave Hansen <dave-gkUM19QKKo4@public.gmane.org>, Thomas Gleixner <tglx-hfZtesqFncYOwBW4kG4KsQ@public.gmane.org>, "open list:DOCUMENTATION" <linux-doc-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>, Linux-MM <linux-mm-Bw31MaZKKs3YtjvyW6yDsg@public.gmane.org>, Khalid Aziz <khalid.aziz-QHcLZuEGTsvQT0dZR+AlfA@public.gmane.org>, deepa.srinivasan-QHcLZuEGTsvQT0dZR+AlfA@public.gmane.org, "H. Peter Anvin" <hpa-YMNOUZJC4hwAvxtiuMwx3w@public.gmane.org>, Ingo Molnar <mingo-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>, X86 ML <x86-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>, iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org, jsteckli-ebkRAfMGSJGzQB+pC5nmwQ@public.gmane.org, Arjan van de Ven <arjan-wEGCiKHe2LqWVfeAwA7xHQ@public.gmane.org>, Peter Zijlstra <a.p.zijlstra-/NLkJaSkS4VmR6Xm/wNWPw@public.gmane.org>, Konrad Rzeszutek Wilk <konrad.wilk-QHcLZuEGTsvQT0dZR+AlfA@public.gmane.org>, Jon Masters <jcm-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>, Greg Kroah-Hartman <gregkh-hQyY1W1yCW8ekmWlsbkhG0B+6BGkLq7r@public.gmane.org>, Borislav Petkov <bp-Gina5bIWoIWzQB+pC5nmwQ@public.gmane.org>, Boris Ostrovsky <boris.ostrovsky-QHcLZuEGTsvQT0dZR+AlfA@public.gmane.org>, chris hyser <chris.hyser-QHcLZuEGTsvQT0dZR+AlfA@public.gmane.org>, linux-arm-kernel <linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org>, Khalid Aziz <khalid-21RPF02GE+GXwddmVfQv5g@public.gmane.org>, Juerg Haefliger <juergh-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>, Andrew Cooper <andrew.cooper3-Sxgqhf6Nn4DQT0dZR+AlfA@public.gmane.org>, LKML <linux-kerne>
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On Wed, Apr 17, 2019 at 12:49:04PM -0700, Andy Lutomirski wrote:
> I also proposed using a gcc plugin (or upstream gcc feature) to add
> some instrumentation to any code that pops RSP to verify that the
> resulting (unsigned) change in RSP is between 0 and THREAD_SIZE bytes.
> This will make ROP quite a bit harder.

I've been playing around with this for a bit, and hope to have
something to post Soon :)

Tycho