From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id BE820C432C0 for ; Wed, 27 Nov 2019 19:44:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9F52A205ED for ; Wed, 27 Nov 2019 19:44:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726970AbfK0ToX (ORCPT ); Wed, 27 Nov 2019 14:44:23 -0500 Received: from outgoing-auth-1.mit.edu ([18.9.28.11]:45242 "EHLO outgoing.mit.edu" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726593AbfK0ToX (ORCPT ); Wed, 27 Nov 2019 14:44:23 -0500 Received: from callcc.thunk.org (97-71-153.205.biz.bhn.net [97.71.153.205] (may be forged)) (authenticated bits=0) (User authenticated as tytso@ATHENA.MIT.EDU) by outgoing.mit.edu (8.14.7/8.12.4) with ESMTP id xARJiFu6029787 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 27 Nov 2019 14:44:16 -0500 Received: by callcc.thunk.org (Postfix, from userid 15806) id 1B71C4202FD; Wed, 27 Nov 2019 14:44:15 -0500 (EST) Date: Wed, 27 Nov 2019 14:44:15 -0500 From: "Theodore Y. Ts'o" To: Jan Kara Cc: linux-ext4@vger.kernel.org, stable@vger.kernel.org Subject: Re: [PATCH] ext4: Fix ext4_empty_dir() for directories with holes Message-ID: <20191127194415.GA22921@mit.edu> References: <20191127131258.1163-1-jack@suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20191127131258.1163-1-jack@suse.cz> User-Agent: Mutt/1.12.2 (2019-09-21) Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org On Wed, Nov 27, 2019 at 02:12:58PM +0100, Jan Kara wrote: > Function ext4_empty_dir() doesn't correctly handle directories with > holes and crashes on bh->b_data dereference when bh is NULL.... Hi Jan, Thanks for the patch. However, it looks like we're still vulnerable to the first block of the directory being NULL? > @@ -2833,19 +2833,25 @@ bool ext4_empty_dir(struct inode *inode) > return true; > > de = (struct ext4_dir_entry_2 *) bh->b_data; ^^^^^^^^^^^ - Ted