In the Linux kernel, the following vulnerability has been resolved:
ocfs2: split transactions in dio completion to avoid credit exhaustion
During ocfs2 dio operations, JBD2 may report warnings via following
call trace:
ocfs2_dio_end_io_write
ocfs2_mark_extent_written
ocfs2_change_extent_flag
ocfs2_split_extent
ocfs2_try_to_merge_extent
ocfs2_extend_rotate_transaction
ocfs2_extend_trans
jbd2__journal_restart
start_this_handle
output: JBD2: kworker/6:2 wants too many credits credits:5450 rsv_credits:0 max:5449
To prevent exceeding the credits limit, modify ocfs2_dio_end_io_write() to
handle extents in a batch of transaction.
Additionally, relocate ocfs2_del_inode_from_orphan(). The orphan inode
should only be removed from the orphan list after the extent tree update
is complete. This ensures that if a crash occurs in the middle of extent
tree updates, we won't leave stale blocks beyond EOF.
This patch also changes the logic for updating the inode size and removing
orphan, making it similar to ext4_dio_write_end_io(). Both operations are
performed only when everything looks good.
Finally, thanks to Jans and Joseph for providing the bug fix prototype and
suggestions.