Message-ID: <4B47C984.1080903@zytor.com>
Date: Fri, 08 Jan 2010 16:10:44 -0800
From: "H. Peter Anvin" <hpa@zytor.com>
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To: Arnd Bergmann <arnd@arndb.de>
CC: Arjan van de Ven <arjan@infradead.org>,
       Heiko Carstens <heiko.carstens@de.ibm.com>, Ingo Molnar <mingo@elte.hu>,
       David Miller <davem@davemloft.net>,
       Andrew Morton <akpm@linux-foundation.org>, linux-kernel@vger.kernel.org
Subject: Re: strict copy_from_user checks issues?
References: <20100104154345.GA5671@osiris.boeblingen.de.ibm.com> <201001071502.29777.arnd@arndb.de> <4B4674FF.5070700@zytor.com> <201001090107.43402.arnd@arndb.de>
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On 01/08/2010 04:07 PM, Arnd Bergmann wrote:
> 
> Also, the calling conventions require you to write slightly more when
> you want to pass down an error value, e.g.
> 
> 	return copy_to_user(uptr, &data, sizeof(data)) ? -EFAULT : 0;
> 
> instead of
> 
> 	return put_user(data, uptr);
> 
> The latter form requires a macro instead of a function for the user copy,
> but we now have that anyway because of the size check.
> 

Well... we already have the latter form?

	-hpa

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