Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Mon, 17 Dec 2001 08:01:30 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Mon, 17 Dec 2001 08:01:20 -0500 Received: from ns.ithnet.com ([217.64.64.10]:20490 "HELO heather.ithnet.com") by vger.kernel.org with SMTP id ; Mon, 17 Dec 2001 08:01:15 -0500 Date: Mon, 17 Dec 2001 14:00:36 +0100 From: Stephan von Krawczynski To: Yoshiki Hayashi Cc: torvalds@transmeta.com, linux-kernel@vger.kernel.org, Marcelo Tosatti Subject: Re: [PATCH] 2.4.16 Fix NULL pointer dereferencing in agpgart_be.c Message-Id: <20011217140036.4a0e8969.skraw@ithnet.com> In-Reply-To: <87zo4iroxw.fsf@u.sanpo.t.u-tokyo.ac.jp> In-Reply-To: <87zo4iroxw.fsf@u.sanpo.t.u-tokyo.ac.jp> Organization: ith Kommunikationstechnik GmbH X-Mailer: Sylpheed version 0.6.6 (GTK+ 1.2.10; i686-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On 17 Dec 2001 21:50:03 +0900 Yoshiki Hayashi wrote: > This patch is against 2.4.16. I couldn't find maintainer in > MAINTAINERS file so I'm simply sending this to Linus and > linux-kernel list. > > In apggart_be.c, if the chip is i830M and the secondary device is not > found, linux kernel tries to dereference NULL pointer. It checks NULL > and returns from the function in the next statement but it's too late. > > The attached patch add NULL check before dereferencing the > pointer to fix the problem. This was solved some weeks ago and the patch is pending somewhere (marcelo?). Unfortunately the complete cure is inside this pending patch, because there are other small tweaks for i830M. The NULL-check is sufficient for non-oops, but i830-register size is smaller than the further ongoings inside agpgart_be.c. Regards, Stephan - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/