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From:   Kees Cook <keescook@chromium.org>
Date:   Tue, 26 Feb 2019 15:40:34 -0800
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Subject: Re: [PATCH 3/3] lkdtm: Check for SMEP clearing protections
To:     Thomas Gleixner <tglx@linutronix.de>
Cc:     Peter Zijlstra <peterz@infradead.org>,
        Jann Horn <jannh@google.com>,
        Sean Christopherson <sean.j.christopherson@intel.com>,
        Dominik Brodowski <linux@dominikbrodowski.net>,
        Kernel Hardening <kernel-hardening@lists.openwall.com>,
        LKML <linux-kernel@vger.kernel.org>
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On Tue, Feb 26, 2019 at 3:37 PM Kees Cook <keescook@chromium.org> wrote:
> +       for (i = 0; i < 64; i++) {
> ...
> +       }
> +       if (i >= 256) {
> +               pr_info("ok: cannot locate cr4 writing call gadget\n");
> +               return;
> +       }

*brown paper bag*
Argh. I changed the depth of that search at the last moment and now
it's mismatched. *sigh* I will send a v2 for this with it fixed.

-- 
Kees Cook