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=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED autolearn=ham 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 DE087C43441 for ; Fri, 9 Nov 2018 05:49:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7C78320825 for ; Fri, 9 Nov 2018 05:49:58 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7C78320825 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=virtuozzo.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727753AbeKIP2y (ORCPT ); Fri, 9 Nov 2018 10:28:54 -0500 Received: from relay.sw.ru ([185.231.240.75]:48408 "EHLO relay.sw.ru" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727087AbeKIP2y (ORCPT ); Fri, 9 Nov 2018 10:28:54 -0500 Received: from [172.16.24.21] by relay.sw.ru with esmtp (Exim 4.90_1) (envelope-from ) id 1gKzfx-0002Bk-P8; Fri, 09 Nov 2018 08:49:50 +0300 From: Vasily Averin Subject: [PATCH v3] ext4: missing !bh check in ext4_xattr_inode_write() To: linux-ext4@vger.kernel.org, Theodore Ts'o , Andreas Dilger Cc: linux-kernel@vger.kernel.org References: <20181108145429.GE22459@thunk.org> Message-ID: <55574e0e-01a9-3cad-34ab-251e340fb78e@virtuozzo.com> Date: Fri, 9 Nov 2018 08:49:48 +0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.2.1 MIME-Version: 1.0 In-Reply-To: <20181108145429.GE22459@thunk.org> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org According to Ted Ts'o ext4_getblk() called in ext4_xattr_inode_write() should not return bh = NULL The only time that bh could be NULL, then, would be in the case of something really going wrong; a programming error elsewhere (perhaps a wild pointer dereference) or I/O error causing on-disk file system corruption (although that would be highly unlikely given that we had *just* allocated the blocks and so the metadata blocks in question probably would still be in the cache). Fixes e50e5129f384 ("ext4: xattr-in-inode support") Cc: stable@kernel.org # 4.13 Signed-off-by: Vasily Averin --- fs/ext4/xattr.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/fs/ext4/xattr.c b/fs/ext4/xattr.c index 0b9688683526..7643d52c776c 100644 --- a/fs/ext4/xattr.c +++ b/fs/ext4/xattr.c @@ -1384,6 +1384,12 @@ static int ext4_xattr_inode_write(handle_t *handle, struct inode *ea_inode, bh = ext4_getblk(handle, ea_inode, block, 0); if (IS_ERR(bh)) return PTR_ERR(bh); + if (!bh) { + WARN_ON_ONCE(1); + EXT4_ERROR_INODE(ea_inode, + "ext4_getblk() return bh = NULL"); + return -EFSCORRUPTED; + } ret = ext4_journal_get_write_access(handle, bh); if (ret) goto out; -- 2.17.1