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Date: Fri, 24 Mar 2017 11:54:52 +0100
From: Ingo Molnar <mingo@kernel.org>
To: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Dave Young <dyoung@redhat.com>, Baoquan He <bhe@redhat.com>,
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        Andrew Morton <akpm@linux-foundation.org>,
        Masahiro Yamada <yamada.masahiro@socionext.com>,
        Bhupesh Sharma <bhsharma@redhat.com>
Subject: Re: [PATCH v2] x86/mm/KASLR: EFI region is mistakenly included into
 KASLR VA space for randomization
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* Ard Biesheuvel <ard.biesheuvel@linaro.org> wrote:

> > Turning KASLR off actively degrades that randomization of the kernel virtual 
> > addresses.
> >
> > Am I missing anything?
> >
> 
> No, I think you are right. UEFI runtime services region are likely to consist of 
> R+W+X mappings for the foreseeable future on x86, and the more we tighten down 
> security in other places, the more appealing the UEFI regions become for 
> exploitation (even if they are only mapped while runtime services calls are in 
> progress).

Ok, so I'm fine with the current proposed patch as a temporary workaround, but 
only if we are going to get a real fix as well, ASAP.

Thanks,

	Ingo