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Subject: Re: Validating Pointers
To: andrew.r.cress@intel.com (Cress, Andrew R)
Date: Thu, 26 Jul 2001 16:52:48 +0100 (BST)
Cc: linux-kernel@vger.kernel.org
In-Reply-To: <no.id> from "Cress, Andrew R" at Jul 26, 2001 08:36:49 AM
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From: Alan Cox <alan@lxorguk.ukuu.org.uk>
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> Is there a general (correct) kernel subroutine to validate a pointer
> received in a routine as input from the outside world?  Is access_ok() a
> good one to use?

access_ok may do minimal checks, or no checking at all. The only point at
which you can validate a user point is when you use copy*user and
get/put_user to access the data.