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Date: Fri, 2 Nov 2001 13:51:37 +0100 (CET)
From: Roman Zippel <zippel@linux-m68k.org>
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To: Ken Ashcraft <kash@stanford.edu>
cc: <linux-kernel@vger.kernel.org>, <engler@stanford.edu>
Subject: Re: null pointer questions
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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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