From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tyler Hicks Subject: Re: [Bugme-new] [Bug 34732] New: BUG: unable to handle kernel NULL pointer dereference at 00000020 Date: Mon, 9 May 2011 16:48:45 -0500 Message-ID: <20110509214844.GA26532@boyd.l.tihix.com> References: <20110509120707.f46b15e9.akpm@linux-foundation.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: linux-fsdevel@vger.kernel.org, bugzilla-daemon@bugzilla.kernel.org, bugme-daemon@bugzilla.kernel.org, Miklos Szeredi , "Rafael J. Wysocki" , baryluk@smp.if.uj.edu.pl To: Andrew Morton Return-path: Received: from e33.co.us.ibm.com ([32.97.110.151]:52531 "EHLO e33.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755080Ab1EIVs4 (ORCPT ); Mon, 9 May 2011 17:48:56 -0400 Received: from d03relay04.boulder.ibm.com (d03relay04.boulder.ibm.com [9.17.195.106]) by e33.co.us.ibm.com (8.14.4/8.13.1) with ESMTP id p49LfoIJ025698 for ; Mon, 9 May 2011 15:41:50 -0600 Received: from d03av04.boulder.ibm.com (d03av04.boulder.ibm.com [9.17.195.170]) by d03relay04.boulder.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id p49Lo0Bm111674 for ; Mon, 9 May 2011 15:50:00 -0600 Received: from d03av04.boulder.ibm.com (loopback [127.0.0.1]) by d03av04.boulder.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id p49FmlFq003260 for ; Mon, 9 May 2011 09:48:48 -0600 Content-Disposition: inline In-Reply-To: <20110509120707.f46b15e9.akpm@linux-foundation.org> Sender: linux-fsdevel-owner@vger.kernel.org List-ID: On Mon May 09, 2011 at 12:07:07PM -0700, Andrew Morton wrote: > I assume this is a post-2.6.38 regression. > > I can't begin to think what might cause this. Is it reproducible? I'd bet on e7c0a167860620bd2938366896964f729ddaeaaa eCryptfs uses lookup_one_len() to lookup lower files, which means that the lower filesystem's d_revalidate() can get a NULL nameidata pointer. That commit dropped the check on nd before dereferencing it. Tyler