Date: Wed, 9 Mar 2016 15:22:12 -0700
From: Jonathan Corbet <corbet@lwn.net>
To: Scotty Bauer <sbauer@eng.utah.edu>
Cc: Ingo Molnar <mingo@kernel.org>, linux-kernel@vger.kernel.org,
        kernel-hardening@lists.openwall.com, x86@kernel.org,
        wmealing@redhat.com, ak@linux.intel.com, luto@amacapital.net,
        Abhiram Balasubramanian <abhiram@cs.utah.edu>,
        Linus Torvalds <torvalds@linux-foundation.org>
Subject: Re: [PATCH v3 1/3] SROP Mitigation: Architecture independent code
 for signal cookies
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	<20160309083204.GA30365@gmail.com>
	<56E09E8B.1010909@eng.utah.edu>
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On Wed, 9 Mar 2016 15:07:07 -0700
Scotty Bauer <sbauer@eng.utah.edu> wrote:

> On 03/09/2016 01:32 AM, Ingo Molnar wrote:
> > 
> > Could you please add a high level description in Documentation
> > that explains the attack and the way how this mitigation code
> > prevents that kind of attack?
> > 
> > Also, the first changelogs should contain more high level
> > description as well. For example, what does the 'verification'
> > of the signal cookie mean, and how does it prevent an SROP
> > attempt?
> > 
> > All of these patches seem to assume that people reading this code
> > know what SROP is and how we defend against it - that is not so.
> 
> I'm going to submit v4 to fix some nits where I'll include the explanation
> and a change log, I apologize for not doing that here. In the meantime if
> you don't mind visiting a link I included a brief explanation on previous
> versions of the patch set.
> 
> https://lkml.org/lkml/2016/2/6/166

The curious might also find background information in my article about this
patch set:

      https://lwn.net/Articles/676803/

(The information still belongs with the patch posting, of course...)

jon