CVE-2026-72370 iomap: release pages on atomic dio size mismatch
A memory leak in the Linux kernel's iomap subsystem can lead to resource exhaustion and denial of service when handling atomic direct I/O size mismatches.
- 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-2026-72370?
CVE-2026-72370 is a memory corruption vulnerability in Linux, published on 15 Aug 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:
iomap: release pages on atomic dio size mismatch
If bio_iov_iter_get_pages() or the bounce helper succeeds but builds a short bio, the REQ_ATOMIC size check rejects it before submission. The old error path only dropped the bio reference, leaving any pages already attached to the bio unreleased.
Release or unbounce the pages before falling through to out_put_bio on this error path.
This bug was reported by sashiko: https://sashiko.dev/#/patchset/20260608073134.95964-1-changfengnan%40bytedance.com
Which versions are affected by CVE-2026-72370?
How do I fix CVE-2026-72370?
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-2026-72370 being exploited?
There is no known exploitation of CVE-2026-72370 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2026-72370, DEBIAN-CVE-2026-72370, GHSA-mf8w-m9qx-f6j9, UBUNTU-CVE-2026-72370.