CVE-2025-21770 iommu: Fix potential memory leak in iopf_queue_remove_device()
A memory leak in the Linux kernel IOMMU driver can lead to resource exhaustion and denial of service when devices are removed with pending page requests.
- 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-2025-21770?
CVE-2025-21770 is a medium-severity denial of service vulnerability in Linux kernel, published on 27 Feb 2025. 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:
iommu: Fix potential memory leak in iopf_queue_remove_device()
The iopf_queue_remove_device() helper removes a device from the per-iommu iopf queue when PRI is disabled on the device. It responds to all outstanding iopf's with an IOMMU_PAGE_RESP_INVALID code and detaches the device from the queue.
However, it fails to release the group structure that represents a group of iopf's awaiting for a response after responding to the hardware. This can cause a memory leak if iopf_queue_remove_device() is called with pending iopf's.
Fix it by calling iopf_free_group() after the iopf group is responded.
Weakness: CWE-401
Which versions are affected by CVE-2025-21770?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2025-21770?
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-2025-21770 being exploited?
There is no known exploitation of CVE-2025-21770 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as BELL-CVE-2025-21770, DEBIAN-CVE-2025-21770, GHSA-9q42-qq54-fwvj, UBUNTU-CVE-2025-21770.