From 6ab88e4863bf4952e014610830d5cd83baefa09a Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Lu=C3=ADs=20Henriques?= Date: Wed, 27 Apr 2022 11:16:38 +0800 Subject: [PATCH] ext4: set csum seed in tmp inode while migrating to extents MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit stable inclusion from stable-v5.10.94 commit da364ab35892f69785266a93bd174f647db1f670 bugzilla: https://gitee.com/openeuler/kernel/issues/I531X9 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=da364ab35892f69785266a93bd174f647db1f670 -------------------------------- commit e81c9302a6c3c008f5c30beb73b38adb0170ff2d upstream. When migrating to extents, the temporary inode will have it's own checksum seed. This means that, when swapping the inodes data, the inode checksums will be incorrect. This can be fixed by recalculating the extents checksums again. Or simply by copying the seed into the temporary inode. Link: https://bugzilla.kernel.org/show_bug.cgi?id=213357 Reported-by: Jeroen van Wolffelaar Signed-off-by: Luís Henriques Link: https://lore.kernel.org/r/20211214175058.19511-1-lhenriques@suse.de Signed-off-by: Theodore Ts'o Cc: stable@kernel.org Signed-off-by: Greg Kroah-Hartman Signed-off-by: Zheng Zengkai Acked-by: Xie XiuQi --- fs/ext4/migrate.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/fs/ext4/migrate.c b/fs/ext4/migrate.c index c5e3fc998211..69cc3f8e03bd 100644 --- a/fs/ext4/migrate.c +++ b/fs/ext4/migrate.c @@ -459,6 +459,17 @@ int ext4_ext_migrate(struct inode *inode) ext4_journal_stop(handle); goto out_unlock; } + /* + * 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; i_size_write(tmp_inode, i_size_read(inode)); /* * Set the i_nlink to zero so it will be deleted later @@ -502,7 +513,6 @@ int ext4_ext_migrate(struct inode *inode) goto out_tmp_inode; } - ei = EXT4_I(inode); i_data = ei->i_data; memset(&lb, 0, sizeof(lb)); -- GitLab