From patchwork Wed Mar 31 12:09:10 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Zhang Yi X-Patchwork-Id: 1460498 Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org (client-ip=23.128.96.18; helo=vger.kernel.org; envelope-from=linux-ext4-owner@vger.kernel.org; receiver=) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by ozlabs.org (Postfix) with ESMTP id 4F9Q0W08R4z9sPf for ; Wed, 31 Mar 2021 23:02:03 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235314AbhCaMBa (ORCPT ); Wed, 31 Mar 2021 08:01:30 -0400 Received: from szxga04-in.huawei.com ([45.249.212.190]:14654 "EHLO szxga04-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235140AbhCaMBT (ORCPT ); Wed, 31 Mar 2021 08:01:19 -0400 Received: from DGGEMS409-HUB.china.huawei.com (unknown [172.30.72.60]) by szxga04-in.huawei.com (SkyGuard) with ESMTP id 4F9PwZ1gv1znWwc; Wed, 31 Mar 2021 19:58:38 +0800 (CST) Received: from huawei.com (10.175.127.227) by DGGEMS409-HUB.china.huawei.com (10.3.19.209) with Microsoft SMTP Server id 14.3.498.0; Wed, 31 Mar 2021 20:01:10 +0800 From: Zhang Yi To: CC: , , , Subject: [PATCH v2] ext4: do not set SB_ACTIVE in ext4_orphan_cleanup() Date: Wed, 31 Mar 2021 20:09:10 +0800 Message-ID: <20210331120910.2223493-1-yi.zhang@huawei.com> X-Mailer: git-send-email 2.25.4 MIME-Version: 1.0 X-Originating-IP: [10.175.127.227] X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-ext4@vger.kernel.org When CONFIG_QUOTA is enabled and if we later fail to finish mounting the filesystem due to some error after ext4_orphan_cleanup(), we may hit use after free issues. The problem is that ext4_orphan_cleanup() sets SB_ACTIVE flag and so inodes processed during the orphan cleanup are put to the superblock's LRU list instead of being immediately destroyed. However the path handling error recovery after failed ->fill_super() call does not destroy inodes attached to the superblock and so they are left active in memory while the superblock is freed. Originally, SB_ACTIVE setting was added so that updated quota information is not destroyed when we drop quota inode references after orphan cleanup. However VFS does not purge dirty inode pages without SB_ACTIVE flag for many years already. So just remove the hack with setting SB_ACTIVE flag from ext4_orphan_cleanup(). Signed-off-by: Zhang Yi Tested-by: Jan Kara Reviewed-by: Jan Kara --- Changes since v1: - Rephrase the changelog as Jan suggested. fs/ext4/super.c | 3 --- 1 file changed, 3 deletions(-) diff --git a/fs/ext4/super.c b/fs/ext4/super.c index b9693680463a..2a33c53b57d8 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -3023,9 +3023,6 @@ static void ext4_orphan_cleanup(struct super_block *sb, sb->s_flags &= ~SB_RDONLY; } #ifdef CONFIG_QUOTA - /* Needed for iput() to work correctly and not trash data */ - sb->s_flags |= SB_ACTIVE; - /* * Turn on quotas which were not enabled for read-only mounts if * filesystem has quota feature, so that they are updated correctly.