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From:   Andreas Schwab <schwab@linux-m68k.org>
To:     David Laight <David.Laight@ACULAB.COM>
Cc:     'Helge Deller' <deller@gmx.de>,
        OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        "linux-parisc@vger.kernel.org" <linux-parisc@vger.kernel.org>
Subject: Re: [PATCH] fat: Use pointer to d_name[0] in put_user() for compat
 case
References: <YgmB01p+p45Cihhg@p100>
        <49a26b7a30254d9fb9653c2f815eaa28@AcuMS.aculab.com>
Date:   Mon, 14 Feb 2022 10:27:32 +0100
In-Reply-To: <49a26b7a30254d9fb9653c2f815eaa28@AcuMS.aculab.com> (David
        Laight's message of "Mon, 14 Feb 2022 09:12:01 +0000")
Message-ID: <8735klx0fv.fsf@igel.home>
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On Feb 14 2022, David Laight wrote:

> The 'bug' is caused by put_user() trying to do:
> 	__typeof__(ptr) __ptr = ptr;
> where __typeof__ is returning char[n] not char *.
>
> I've tried a few things but can't get __typeof__ to
> generate a suitable type for both a simple type and array.

Does it work to use __typeof__(&*(ptr))?

-- 
Andreas Schwab, schwab@linux-m68k.org
GPG Key fingerprint = 7578 EB47 D4E5 4D69 2510  2552 DF73 E780 A9DA AEC1
"And now for something completely different."