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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 94083C43219 for ; Mon, 24 Jan 2022 19:12:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233506AbiAXTMy (ORCPT ); Mon, 24 Jan 2022 14:12:54 -0500 Received: from ams.source.kernel.org ([145.40.68.75]:36936 "EHLO ams.source.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1347384AbiAXTKV (ORCPT ); Mon, 24 Jan 2022 14:10:21 -0500 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id BCC9EB8122A; Mon, 24 Jan 2022 19:10:19 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1C1E6C340E7; Mon, 24 Jan 2022 19:10:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1643051418; bh=WGNVpAlelXoXa7YIBX5GGnhU0Tj3kAZDb3k7l8hJze8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=mpmGC/LKDX1fylYeEfjq2Xz92WX7JuNvWp/KXj9ei2+FmfdCq1tZTOy+MuX5wcYyL 6k1Rj7Amm7dR+iWTxQt465nP3XPJSgJ+mOhMeEzhFfVypBDhhWfJgHukGaK1X+gR/o mgmC+tTEuX2H3yusdxdbL93iOL35IntI4mZmrdnk= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Theodore Tso , Lukas Czerner , stable@kernel.org Subject: [PATCH 4.14 156/186] ext4: dont use the orphan list when migrating an inode Date: Mon, 24 Jan 2022 19:43:51 +0100 Message-Id: <20220124183942.116336411@linuxfoundation.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20220124183937.101330125@linuxfoundation.org> References: <20220124183937.101330125@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Theodore Ts'o commit 6eeaf88fd586f05aaf1d48cb3a139d2a5c6eb055 upstream. We probably want to remove the indirect block to extents migration feature after a deprecation window, but until then, let's fix a potential data loss problem caused by the fact that we put the tmp_inode on the orphan list. In the unlikely case where we crash and do a journal recovery, the data blocks belonging to the inode being migrated are also represented in the tmp_inode on the orphan list --- and so its data blocks will get marked unallocated, and available for reuse. Instead, stop putting the tmp_inode on the oprhan list. So in the case where we crash while migrating the inode, we'll leak an inode, which is not a disaster. It will be easily fixed the next time we run fsck, and it's better than potentially having blocks getting claimed by two different files, and losing data as a result. Signed-off-by: Theodore Ts'o Reviewed-by: Lukas Czerner Cc: stable@kernel.org Signed-off-by: Greg Kroah-Hartman --- fs/ext4/migrate.c | 19 ++++--------------- 1 file changed, 4 insertions(+), 15 deletions(-) --- a/fs/ext4/migrate.c +++ b/fs/ext4/migrate.c @@ -462,12 +462,12 @@ int ext4_ext_migrate(struct inode *inode percpu_down_write(&sbi->s_writepages_rwsem); /* - * Worst case we can touch the allocation bitmaps, a bgd - * block, and a block to link in the orphan list. We do need - * need to worry about credits for modifying the quota inode. + * Worst case we can touch the allocation bitmaps and a block + * group descriptor block. We do need need to worry about + * credits for modifying the quota inode. */ handle = ext4_journal_start(inode, EXT4_HT_MIGRATE, - 4 + EXT4_MAXQUOTAS_TRANS_BLOCKS(inode->i_sb)); + 3 + EXT4_MAXQUOTAS_TRANS_BLOCKS(inode->i_sb)); if (IS_ERR(handle)) { retval = PTR_ERR(handle); @@ -488,10 +488,6 @@ int ext4_ext_migrate(struct inode *inode * Use the correct seed for checksum (i.e. the seed from 'inode'). This * is so that the metadata blocks will have the correct checksum after * the migration. - * - * Note however that, if a crash occurs during the migration process, - * the recovery process is broken because the tmp_inode checksums will - * be wrong and the orphans cleanup will fail. */ ei = EXT4_I(inode); EXT4_I(tmp_inode)->i_csum_seed = ei->i_csum_seed; @@ -503,7 +499,6 @@ int ext4_ext_migrate(struct inode *inode clear_nlink(tmp_inode); ext4_ext_tree_init(handle, tmp_inode); - ext4_orphan_add(handle, tmp_inode); ext4_journal_stop(handle); /* @@ -528,12 +523,6 @@ int ext4_ext_migrate(struct inode *inode handle = ext4_journal_start(inode, EXT4_HT_MIGRATE, 1); if (IS_ERR(handle)) { - /* - * It is impossible to update on-disk structures without - * a handle, so just rollback in-core changes and live other - * work to orphan_list_cleanup() - */ - ext4_orphan_del(NULL, tmp_inode); retval = PTR_ERR(handle); goto out_tmp_inode; }