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Date: Fri, 2 Nov 2001 15:16:09 +0200 (EET)
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To: Roman Zippel <zippel@linux-m68k.org>
cc: <linux-kernel@vger.kernel.org>, <engler@stanford.edu>
Subject: Re: null pointer questions
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On Fri, 2 Nov 2001, Roman Zippel wrote:

> Hi,
> 
> On Thu, 1 Nov 2001, Ken Ashcraft wrote:
> 
> > 1. If I pass size 0 to kmalloc, what does it return?
> 
> AFAIK size is always rounded up, so you get the smallest possible
> allocation unit.
> 
> > 2. What happens if I pass a null pointer as the destination parameter
> > to copy_from_user?  Does copy_from_user handle it safely or will the
> > kernel seg fault?
> 
> The kernel won't crash, but it might fail (depending on whether 0 is a
> valid user space address or not).
> 
> bye, Roman
> 
> 
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