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Date:   Mon, 13 Dec 2021 20:27:42 +0000
From:   Matthew Wilcox <willy@infradead.org>
To:     William Kucharski <william.kucharski@oracle.com>
Cc:     Kees Cook <keescook@chromium.org>,
        "linux-mm@kvack.org" <linux-mm@kvack.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        "linux-hardening@vger.kernel.org" <linux-hardening@vger.kernel.org>
Subject: Re: [PATCH v3 0/3] Assorted improvements to usercopy
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 <196BFB9E-9A72-48B1-863E-021DE0B162A7@oracle.com>
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On Mon, Dec 13, 2021 at 07:18:57PM +0000, William Kucharski wrote:
> I like these, but a quick question:
> 
> Since the usercopy_abort() calls are all because the offset exceeds the page
> size, is there a reason why you don't specifically state that via the detail
> parameter rather than just supply a NULL pointer?

Hmm ... I'd defer to Kees on this, because I'm not familiar with
usercopy_abort() usage, but the only places which use the detail
parameter today are slab/slub, which use it to pass the name of
the slab.  I think the user is supposed to infer that we overran the
end of the page based on the offset & length values.

> Otherwise for the patch series:
> 
> Reviewed-by: William Kucharski <william.kucharski@oracle.com>

Thanks!