From patchwork Mon Mar 15 13:54:08 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 401272 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=-19.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT 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 9C35DC433E6 for ; Mon, 15 Mar 2021 14:06:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 70A3F64F06 for ; Mon, 15 Mar 2021 14:06:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234874AbhCOOF6 (ORCPT ); Mon, 15 Mar 2021 10:05:58 -0400 Received: from mail.kernel.org ([198.145.29.99]:37820 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233279AbhCOOBV (ORCPT ); Mon, 15 Mar 2021 10:01:21 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 572FC64F5D; Mon, 15 Mar 2021 14:00:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1615816857; bh=l9t/jy+7hTt25NJiy8W2DlxlKVv9HV05Irxdw8Kn1YI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=hyyip4fKh6x1vjHbjqEgzCs/mDp1cyZ9y5SnH+5JqZOZPS36ufI6xNlhN0XodbaTr n0CVjoWoTHTtyM+s/bNomZT9gGAY/keJm1V16nocVBRvNu8R9kq5yPFFiui867lna2 atV3rSKTWqzT2wn+pOMtgOARV+Q+BgSru2BRdd24= From: gregkh@linuxfoundation.org To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Murphy Zhou , Jan Kara , Theodore Tso , Sasha Levin Subject: [PATCH 5.10 155/290] ext4: dont try to processed freed blocks until mballoc is initialized Date: Mon, 15 Mar 2021 14:54:08 +0100 Message-Id: <20210315135547.155524013@linuxfoundation.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210315135541.921894249@linuxfoundation.org> References: <20210315135541.921894249@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Greg Kroah-Hartman From: Theodore Ts'o [ Upstream commit 027f14f5357279655c3ebc6d14daff8368d4f53f ] If we try to make any changes via the journal between when the journal is initialized, but before the multi-block allocated is initialized, we will end up deferencing a NULL pointer when the journal commit callback function calls ext4_process_freed_data(). The proximate cause of this failure was commit 2d01ddc86606 ("ext4: save error info to sb through journal if available") since file system corruption problems detected before the call to ext4_mb_init() would result in a journal commit before we aborted the mount of the file system.... and we would then trigger the NULL pointer deref. Link: https://lore.kernel.org/r/YAm8qH/0oo2ofSMR@mit.edu Reported-by: Murphy Zhou Reviewed-by: Jan Kara Signed-off-by: Theodore Ts'o Signed-off-by: Sasha Levin --- fs/ext4/super.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/fs/ext4/super.c b/fs/ext4/super.c index ea5aefa23a20..e30bf8f342c2 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -4876,7 +4876,6 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent) set_task_ioprio(sbi->s_journal->j_task, journal_ioprio); - sbi->s_journal->j_commit_callback = ext4_journal_commit_callback; sbi->s_journal->j_submit_inode_data_buffers = ext4_journal_submit_inode_data_buffers; sbi->s_journal->j_finish_inode_data_buffers = @@ -4993,6 +4992,14 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent) goto failed_mount5; } + /* + * We can only set up the journal commit callback once + * mballoc is initialized + */ + if (sbi->s_journal) + sbi->s_journal->j_commit_callback = + ext4_journal_commit_callback; + block = ext4_count_free_clusters(sb); ext4_free_blocks_count_set(sbi->s_es, EXT4_C2B(sbi, block));