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Date: Wed, 16 Nov 2016 09:51:30 +0100
From: Greg KH <gregkh@linuxfoundation.org>
To: Ingo Molnar <mingo@kernel.org>
Cc: Kees Cook <keescook@chromium.org>,
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Subject: Re: [RFC][PATCH 7/7] kref: Implement using refcount_t
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On Wed, Nov 16, 2016 at 09:31:55AM +0100, Ingo Molnar wrote:
> So what I'd love to see is to have a kernel option that re-introduces some 
> historic root (and other) holes that can be exploited deterministically - 
> obviously default disabled.

Ick, I don't want to have to support nasty #ifdefs for
"CONFIG_TOTALLY_INSECURE" type options in code logic for the next 20+
years, do you?

> I'd restrict this to reasonably 'deterministic' holes, and the exploits themselves 
> could be somewhere in tools/. (Obviously only where the maintainers agree to host 
> the code.) They wouldn't give a root shell, they'd only test whether they reached 
> uid0 (or some other elevated privilege).

Having exploits in tools/ would be good, I would like to see that, as
then we can ensure that we don't ever introduce old problems that we
have fixed again in the future.  That I have no objection to.

thanks,

greg k-h