From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754869AbXGHRC7 (ORCPT ); Sun, 8 Jul 2007 13:02:59 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752006AbXGHRCu (ORCPT ); Sun, 8 Jul 2007 13:02:50 -0400 Received: from smtp2.linux-foundation.org ([207.189.120.14]:51867 "EHLO smtp2.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751836AbXGHRCt (ORCPT ); Sun, 8 Jul 2007 13:02:49 -0400 Date: Sun, 8 Jul 2007 10:02:30 -0700 (PDT) From: Linus Torvalds To: Markus Trippelsdorf cc: Andrew Morton , linux-kernel@vger.kernel.org, drepper@redhat.com Subject: Re: 2.6.22-rc6(mm1) Unable to handle kernel NULL pointer dereference - git-bisect result In-Reply-To: <20070708152808.GA5902@gentoox2.trippelsdorf.de> Message-ID: References: <20070708051452.GA4140@gentoox2.trippelsdorf.de> <20070708012016.455ce8d5.akpm@linux-foundation.org> <20070708100911.GA4196@gentoox2.trippelsdorf.de> <20070708152808.GA5902@gentoox2.trippelsdorf.de> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=us-ascii Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Sun, 8 Jul 2007, Markus Trippelsdorf wrote: > > I tested this further and it turned out that the Linus tree is also > affected. So I ran git-bisect, after I found out that version > 2.6.21.6 was not affected by this bug. git-bisect is wonderful. > gentoox2 linux # git bisect bad > 1c710c896eb461895d3c399e15bb5f20b39c9073 is first bad commit > commit 1c710c896eb461895d3c399e15bb5f20b39c9073 > Author: Ulrich Drepper Ok, I see what's wrong. We're doing "vfs_permission()" and passing in "nd" to it when "times" is NULL, but Uli didn't even *initialize* it for the case of filename == NULL && dfd != AT_FDCWD so yeah, it's broken. I was planning on doing 2.6.22 today, so I'm actually inclined to revert the commit entirely, even though it looks like it's probably fairly trivial to fix. But if we get a really quick and obvious fix, I guess I'll apply it. I have to say, the new do_utimes() code is pretty ugly compared to the old one exactly in the added special cases (the ones that caused this bug..) Uli? Linus