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=-3.9 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, 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 58AC4C65BAF for ; Sun, 9 Dec 2018 22:16:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 27F0520661 for ; Sun, 9 Dec 2018 22:16:50 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 27F0520661 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=decadent.org.uk 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 S1727370AbeLIWHq (ORCPT ); Sun, 9 Dec 2018 17:07:46 -0500 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:37236 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727295AbeLIWHm (ORCPT ); Sun, 9 Dec 2018 17:07:42 -0500 Received: from pub.yeoldevic.com ([81.174.156.145] helo=deadeye) by shadbolt.decadent.org.uk with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.89) (envelope-from ) id 1gW738-0002ij-8s; Sun, 09 Dec 2018 21:55:42 +0000 Received: from ben by deadeye with local (Exim 4.91) (envelope-from ) id 1gW72f-0003TO-Hn; Sun, 09 Dec 2018 21:55:13 +0000 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Theodore Ts'o" , "Maxim Malkov" Date: Sun, 09 Dec 2018 21:50:33 +0000 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) X-Patchwork-Hint: ignore Subject: [PATCH 3.16 188/328] ext4: prevent online resize with backup superblock In-Reply-To: X-SA-Exim-Connect-IP: 81.174.156.145 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.62-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Theodore Ts'o commit 011fa99404bea3f5d897c4983f6bd51170e3b18f upstream. Prevent BUG or corrupted file systems after the following: mkfs.ext4 /dev/vdc 100M mount -t ext4 -o sb=40961 /dev/vdc /vdc resize2fs /dev/vdc We previously prevented online resizing using the old resize ioctl. Move the code to ext4_resize_begin(), so the check applies for all of the resize ioctl's. Reported-by: Maxim Malkov Signed-off-by: Theodore Ts'o Signed-off-by: Ben Hutchings --- fs/ext4/resize.c | 24 ++++++++++++------------ 1 file changed, 12 insertions(+), 12 deletions(-) --- a/fs/ext4/resize.c +++ b/fs/ext4/resize.c @@ -24,6 +24,18 @@ int ext4_resize_begin(struct super_block return -EPERM; /* + * If we are not using the primary superblock/GDT copy don't resize, + * because the user tools have no way of handling this. Probably a + * bad time to do it anyways. + */ + if (EXT4_SB(sb)->s_sbh->b_blocknr != + le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block)) { + ext4_warning(sb, "won't resize using backup superblock at %llu", + (unsigned long long)EXT4_SB(sb)->s_sbh->b_blocknr); + return -EPERM; + } + + /* * We are not allowed to do online-resizing on a filesystem mounted * with error, because it can destroy the filesystem easily. */ @@ -758,18 +770,6 @@ static int add_new_gdb(handle_t *handle, "EXT4-fs: ext4_add_new_gdb: adding group block %lu\n", gdb_num); - /* - * If we are not using the primary superblock/GDT copy don't resize, - * because the user tools have no way of handling this. Probably a - * bad time to do it anyways. - */ - if (EXT4_SB(sb)->s_sbh->b_blocknr != - le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block)) { - ext4_warning(sb, "won't resize using backup superblock at %llu", - (unsigned long long)EXT4_SB(sb)->s_sbh->b_blocknr); - return -EPERM; - } - gdb_bh = sb_bread(sb, gdblock); if (!gdb_bh) return -EIO;