linux/fs/jbd2
Zhihao Cheng e34c8dd238 jbd2: Fix wrongly judgement for buffer head removing while doing checkpoint
Following process,

jbd2_journal_commit_transaction
// there are several dirty buffer heads in transaction->t_checkpoint_list
          P1                   wb_workfn
jbd2_log_do_checkpoint
 if (buffer_locked(bh)) // false
                            __block_write_full_page
                             trylock_buffer(bh)
                             test_clear_buffer_dirty(bh)
 if (!buffer_dirty(bh))
  __jbd2_journal_remove_checkpoint(jh)
   if (buffer_write_io_error(bh)) // false
                             >> bh IO error occurs <<
 jbd2_cleanup_journal_tail
  __jbd2_update_log_tail
   jbd2_write_superblock
   // The bh won't be replayed in next mount.
, which could corrupt the ext4 image, fetch a reproducer in [Link].

Since writeback process clears buffer dirty after locking buffer head,
we can fix it by try locking buffer and check dirtiness while buffer is
locked, the buffer head can be removed if it is neither dirty nor locked.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=217490
Fixes: 470decc613 ("[PATCH] jbd2: initial copy of files from jbd")
Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20230606135928.434610-5-yi.zhang@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2023-07-10 23:09:21 -04:00
..
checkpoint.c jbd2: Fix wrongly judgement for buffer head removing while doing checkpoint 2023-07-10 23:09:21 -04:00
commit.c jbd2: remove t_checkpoint_io_list 2023-07-10 23:09:21 -04:00
journal.c Various cleanups and bug fixes in ext4's extent status tree, 2023-06-29 13:18:36 -07:00
Kconfig treewide: Add SPDX license identifier - Makefile/Kconfig 2019-05-21 10:50:46 +02:00
Makefile treewide: Add SPDX license identifier - Makefile/Kconfig 2019-05-21 10:50:46 +02:00
recovery.c jbd2: continue to record log between each mount 2023-06-26 19:35:13 -04:00
revoke.c jbd2: rename jbd_debug() to jbd2_debug() 2022-08-02 23:52:19 -04:00
transaction.c jdb2: Don't refuse invalidation of already invalidated buffers 2023-04-14 19:38:50 -04:00