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Date:   Mon, 3 Oct 2022 15:28:47 -0700
From:   Kees Cook <keescook@chromium.org>
To:     Rick Edgecombe <rick.p.edgecombe@intel.com>
Cc:     x86@kernel.org, "H . Peter Anvin" <hpa@zytor.com>,
        Thomas Gleixner <tglx@linutronix.de>,
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        Balbir Singh <bsingharora@gmail.com>,
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Subject: Re: [PATCH v2 29/39] x86/cet/shstk: Support wrss for userspace
Message-ID: <202210031525.78F3FA8@keescook>
References: <20220929222936.14584-1-rick.p.edgecombe@intel.com>
 <20220929222936.14584-30-rick.p.edgecombe@intel.com>
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On Thu, Sep 29, 2022 at 03:29:26PM -0700, Rick Edgecombe wrote:
> For the current shadow stack implementation, shadow stacks contents easily
> be arbitrarily provisioned with data.

I can't parse this sentence.

> This property helps apps protect
> themselves better, but also restricts any potential apps that may want to
> do exotic things at the expense of a little security.

Is anything using this right now? Wouldn't thing be safer without WRSS?
(Why can't we skip this patch?)

-- 
Kees Cook