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Date:   Wed, 14 Dec 2022 13:49:00 -0800
From:   Kees Cook <keescook@chromium.org>
To:     Andy Shevchenko <andy.shevchenko@gmail.com>
Cc:     Paulo Miguel Almeida <paulo.miguel.almeida.rodenas@gmail.com>,
        Arnd Bergmann <arnd@arndb.de>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Ilpo =?iso-8859-1?Q?J=E4rvinen?= <ilpo.jarvinen@linux.intel.com>,
        Jiri Slaby <jirislaby@kernel.org>,
        Haowen Bai <baihaowen@meizu.com>, linux-kernel@vger.kernel.org,
        linux-hardening@vger.kernel.org
Subject: Re: [PATCH] [next] pcmcia: synclink_cs: replace 1-element array with
 flex-array member
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On Wed, Dec 14, 2022 at 10:39:52PM +0200, Andy Shevchenko wrote:
> Yes, and Try to make it work with __packed. As I said, the problem is
> that the code is relying on something which is architecture dependent
> strictly speaking. And hence I disagree with Kees that v2 is okay to
> go.

I meant that v2 is functionally identical to the existing code.

> The full change should be something like
> 
> check_add(sizeof(), max_frame_size)
> kcalloc(8, size)

Right -- this would fix the existing mistakes in size calculation (and
is certainly better).

-- 
Kees Cook