jbd2: use a per-journal lock_class_key for jbd2_trans_commit_key

commit 524c3853831cf4f7e1db579e487c757c3065165c upstream.

syzbot is reporting possibility of deadlock due to sharing lock_class_key
for jbd2_handle across ext4 and ocfs2. But this is a false positive, for
one disk partition can't have two filesystems at the same time.

Reported-by: syzbot+6e493c165d26d6fcbf72@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=6e493c165d26d6fcbf72
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Tested-by: syzbot+6e493c165d26d6fcbf72@syzkaller.appspotmail.com
Reviewed-by: Jan Kara <jack@suse.cz>
Message-ID: <987110fc-5470-457a-a218-d286a09dd82f@I-love.SAKURA.ne.jp>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Tetsuo Handa
2025-10-22 20:11:37 +09:00
committed by Greg Kroah-Hartman
parent 79a0e4d3fb
commit 815327958e
2 changed files with 10 additions and 2 deletions

View File

@@ -1563,7 +1563,6 @@ static journal_t *journal_init_common(struct block_device *bdev,
struct block_device *fs_dev,
unsigned long long start, int len, int blocksize)
{
static struct lock_class_key jbd2_trans_commit_key;
journal_t *journal;
int err;
int n;
@@ -1572,6 +1571,7 @@ static journal_t *journal_init_common(struct block_device *bdev,
if (!journal)
return ERR_PTR(-ENOMEM);
lockdep_register_key(&journal->jbd2_trans_commit_key);
journal->j_blocksize = blocksize;
journal->j_dev = bdev;
journal->j_fs_dev = fs_dev;
@@ -1601,7 +1601,7 @@ static journal_t *journal_init_common(struct block_device *bdev,
journal->j_max_batch_time = 15000; /* 15ms */
atomic_set(&journal->j_reserved_credits, 0);
lockdep_init_map(&journal->j_trans_commit_map, "jbd2_handle",
&jbd2_trans_commit_key, 0);
&journal->jbd2_trans_commit_key, 0);
/* The journal is marked for error until we succeed with recovery! */
journal->j_flags = JBD2_ABORT;
@@ -1648,6 +1648,7 @@ err_cleanup:
kfree(journal->j_wbuf);
jbd2_journal_destroy_revoke(journal);
journal_fail_superblock(journal);
lockdep_unregister_key(&journal->jbd2_trans_commit_key);
kfree(journal);
return ERR_PTR(err);
}
@@ -2229,6 +2230,7 @@ int jbd2_journal_destroy(journal_t *journal)
crypto_free_shash(journal->j_chksum_driver);
kfree(journal->j_fc_wbuf);
kfree(journal->j_wbuf);
lockdep_unregister_key(&journal->jbd2_trans_commit_key);
kfree(journal);
return err;

View File

@@ -1266,6 +1266,12 @@ struct journal_s
*/
struct lockdep_map j_trans_commit_map;
#endif
/**
* @jbd2_trans_commit_key:
*
* "struct lock_class_key" for @j_trans_commit_map
*/
struct lock_class_key jbd2_trans_commit_key;
/**
* @j_fc_cleanup_callback: