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Date:   Fri, 12 Oct 2018 01:15:01 +0200 (CEST)
From:   Thomas Gleixner <tglx@linutronix.de>
To:     Jann Horn <jannh@google.com>
cc:     Kees Cook <keescook@chromium.org>,
        Andy Lutomirski <luto@kernel.org>, kristen@linux.intel.com,
        Kernel Hardening <kernel-hardening@lists.openwall.com>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        "H . Peter Anvin" <hpa@zytor.com>,
        the arch/x86 maintainers <x86@kernel.org>,
        kernel list <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] x86: entry: flush the cache if syscall error
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On Thu, 11 Oct 2018, Jann Horn wrote:
> On Thu, Oct 11, 2018 at 10:56 PM Kees Cook <keescook@chromium.org> wrote:
> > Seems like just changing this with "ax == 0" into "ax >= 0" would solve that?
> 
> As spender points out on twitter
> (https://twitter.com/grsecurity/status/1050497259937370118 - thanks,
> spender!), struct pt_regs stores register values as "unsigned long",
> and so you'll need to use something like IS_ERR_VALUE().

Ha, so it's not only me who noticed, but then I'm not reading twitter...

Thanks,

	tglx