CVE-2026-80881 ocfs2: fix buffer head management in ocfs2_read_blocks()
A flaw in the Linux kernel OCFS2 filesystem allows attackers to corrupt memory or cause denial of service by exploiting improper buffer head management.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-80881?
CVE-2026-80881 is a memory corruption vulnerability in Linux, published on 4 Sep 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: fix buffer head management in ocfs2_read_blocks()
In ocfs2_read_blocks(), caller should't assume that buffer head returned by 'sb_getblk()' is exclusively owned and so 'put_bh()' always drops b_count from 1 to 0. If it is not so, buffer head remains on hold and likely to be returned by the next call to 'sb_getblk()' unchanged - that is, with BH_Uptodate bit set even if it has failed validation previously, thus allowing to insert that buffer head into OCFS2 metadata cache and submit it to upper layers. To avoid such a scenario, BH_Uptodate should be cleared immediately after 'validate()' callback has detected some data inconsistency.
Which versions are affected by CVE-2026-80881?
How do I fix CVE-2026-80881?
Apply the vendor's patch.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2026-80881 being exploited?
There is no known exploitation of CVE-2026-80881 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2026-80881, DEBIAN-CVE-2026-80881, GHSA-5x8p-2x56-54gv, UBUNTU-CVE-2026-80881.