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Date:   Mon, 14 Feb 2022 11:13:56 +0100
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Subject: Re: [PATCH] fat: Use pointer to d_name[0] in put_user() for compat
 case
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To:     Andreas Schwab <schwab@linux-m68k.org>,
        David Laight <David.Laight@ACULAB.COM>
Cc:     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>
References: <YgmB01p+p45Cihhg@p100>
 <49a26b7a30254d9fb9653c2f815eaa28@AcuMS.aculab.com>
 <8735klx0fv.fsf@igel.home>
From:   Helge Deller <deller@gmx.de>
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On 2/14/22 10:27, Andreas Schwab wrote:
> On Feb 14 2022, David Laight wrote:
>
>> The 'bug' is caused by put_user() trying to do:
>> 	__typeof__(ptr) __ptr =3D 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))?

Yes, this works.

Helge