# CVE-2025-22094: powerpc/perf: Fix ref-counting on the PMU 'vpa_pmu'

> A missing reference count in the Linux kernel powerpc perf subsystem allows unloading a module while active, causing a null pointer dereference and kernel panic.

- **Severity:** High 7.3 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** A user has to click or open something
- **Fix available:** Yes
- **Published:** 16 Apr 2025
- **Updated:** 5 Aug 2026
- **Also known as:** BELL-CVE-2025-22094, GHSA-2879-fhf4-rjj6, ROOT-OS-DEBIAN-13-CVE-2025-22094, UBUNTU-CVE-2025-22094

## What is CVE-2025-22094?

CVE-2025-22094 is a high-severity vulnerability in Linux kernel, published on 16 Apr 2025. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.

### Official description

In the Linux kernel, the following vulnerability has been resolved:

powerpc/perf: Fix ref-counting on the PMU 'vpa_pmu'

Commit 176cda0619b6 ("powerpc/perf: Add perf interface to expose vpa
counters") introduced 'vpa_pmu' to expose Book3s-HV nested APIv2 provided
L1<->L2 context switch latency counters to L1 user-space via
perf-events. However the newly introduced PMU named 'vpa_pmu' doesn't
assign ownership of the PMU to the module 'vpa_pmu'. Consequently the
module 'vpa_pmu' can be unloaded while one of the perf-events are still
active, which can lead to kernel oops and panic of the form below on a
Pseries-LPAR:

BUG: Kernel NULL pointer dereference on read at 0x00000058
<snip>
 NIP [c000000000506cb8] event_sched_out+0x40/0x258
 LR [c00000000050e8a4] __perf_remove_from_context+0x7c/0x2b0
 Call Trace:
 [c00000025fc3fc30] [c00000025f8457a8] 0xc00000025f8457a8 (unreliable)
 [c00000025fc3fc80] [fffffffffffffee0] 0xfffffffffffffee0
 [c00000025fc3fcd0] [c000000000501e70] event_function+0xa8/0x120
<snip>
 Kernel panic - not syncing: Aiee, killing interrupt handler!

Fix this by adding the module ownership to 'vpa_pmu' so that the module
'vpa_pmu' is ref-counted and prevented from being unloaded when perf-events
are initialized.

Weakness: CWE-476 (NULL Pointer Dereference)

## Which versions are affected by CVE-2025-22094?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2025-22094?

Apply the vendor's patch.

## Is CVE-2025-22094 being exploited?

There is no known exploitation of CVE-2025-22094 in the wild and no public exploit code.

## Other vulnerabilities in Linux kernel

- [CVE-2026-53266](https://insights.sbomify.com/CVE-2026-53266/): Linux Kernel Out-of-Bounds Write (high 8.8, exploited in the wild)
- [CVE-2013-6282](https://insights.sbomify.com/CVE-2013-6282/): Linux Kernel Improper Input Validation (high 8.8, exploited in the wild)
- [CVE-2022-0185](https://insights.sbomify.com/CVE-2022-0185/): Linux Kernel Heap-Based Buffer Overflow (high 8.4, exploited in the wild)
- [CVE-2013-2094](https://insights.sbomify.com/CVE-2013-2094/): Linux Kernel Privilege Escalation (high 8.4, exploited in the wild)
- [CVE-2026-53362](https://insights.sbomify.com/CVE-2026-53362/): Linux Kernel Unspecified (high 7.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-22094 and fix it if it is affected.

What it is: CVE-2025-22094 is a high-severity vulnerability in Linux kernel, published on 16 Apr 2025. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2025-22094 in the wild and no public exploit code.

Affected product: Linux kernel. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2025-22094/ (Markdown: https://insights.sbomify.com/CVE-2025-22094/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-22094
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-22094
- OSV: https://osv.dev/vulnerability/CVE-2025-22094

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-22094/
Summaries are generated and may contain mistakes; the official description above is the record.