CVE-2026-46080 ocfs2: split transactions in dio completion to avoid credit exhaustion
A flaw in the Linux kernel's OCFS2 filesystem can cause JBD2 credit exhaustion during direct I/O completion, leading to system warnings and potential denial of service.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-46080?
CVE-2026-46080 is a medium-severity denial of service vulnerability in Linux kernel, published on 27 May 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
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.
Which versions are affected by CVE-2026-46080?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2026-46080?
Apply the vendor's patch.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-46080 being exploited?
There is no known exploitation of CVE-2026-46080 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as AZL-88698, BELL-CVE-2026-46080, DEBIAN-CVE-2026-46080, GHSA-8mmh-cvrq-r3x6, ROOT-OS-DEBIAN-11-CVE-2026-46080, ROOT-OS-DEBIAN-12-CVE-2026-46080 and 3 more.