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From:   Kees Cook <keescook@chromium.org>
Date:   Tue, 8 Jan 2019 16:56:03 -0800
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Subject: Re: [PATCH 1/2] x86/pkeys: copy pkey state at fork()
To:     Dave Hansen <dave.hansen@intel.com>
Cc:     Dave Hansen <dave.hansen@linux.intel.com>,
        LKML <linux-kernel@vger.kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        "H. Peter Anvin" <hpa@zytor.com>, X86 ML <x86@kernel.org>,
        Peter Zijlstra <peterz@infradead.org>,
        Michael Ellerman <mpe@ellerman.id.au>,
        Will Deacon <will.deacon@arm.com>,
        Andy Lutomirski <luto@kernel.org>,
        Joerg Roedel <jroedel@suse.de>,
        Daniel Micay <danielmicay@gmail.com>
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On Tue, Nov 20, 2018 at 1:14 PM Kees Cook <keescook@chromium.org> wrote:
>
> On Fri, Oct 26, 2018 at 12:59 PM, Dave Hansen <dave.hansen@intel.com> wrote:
> > On 10/26/18 12:51 PM, Dave Hansen wrote:
> > ...
> >> The result is that, after a fork(), the child's pkey state ends up
> >> looking like it does after an execve(), which is totally wrong.  pkeys
> >> that are already allocated can be allocated again, for instance.
> >
> > One thing I omitted.  This was very nicely discovered and reported by
> > danielmicay@gmail.com.  Thanks, Daniel!
>
> Thread ping. Is there a v2 of this, or can this go in as-is? Looks good to me:
>
> Reviewed-by: Kees Cook <keescook@chromium.org>

Ingo, can you take these two patches? Use of pkeys is still buggy
without it. (And probably should have a Cc: stable tag too.)

-Kees

-- 
Kees Cook