# CVE-2025-38515: drm/sched: Increment job count before swapping tail spsc queue

> A race condition in the Linux kernel DRM scheduler can cause job scheduling hangs, leading to a denial of service.

- **Severity:** Medium 4.7 (`CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H`)
- **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:** Yes
- **Published:** 16 Aug 2025
- **Updated:** 11 May 2026
- **Also known as:** AZL-66392, AZL-73545, BELL-CVE-2025-38515, DEBIAN-CVE-2025-38515, GHSA-6wqf-m4v2-8ppm, ROOT-OS-DEBIAN-11-CVE-2025-38515, ROOT-OS-DEBIAN-12-CVE-2025-38515, ROOT-OS-DEBIAN-13-CVE-2025-38515, ROOT-OS-UBUNTU-2404-CVE-2025-38515, UBUNTU-CVE-2025-38515

## What is CVE-2025-38515?

CVE-2025-38515 is a medium-severity vulnerability in Debian Debian Linux, published on 16 Aug 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:

drm/sched: Increment job count before swapping tail spsc queue

A small race exists between spsc_queue_push and the run-job worker, in
which spsc_queue_push may return not-first while the run-job worker has
already idled due to the job count being zero. If this race occurs, job
scheduling stops, leading to hangs while waiting on the job’s DMA
fences.

Seal this race by incrementing the job count before appending to the
SPSC queue.

This race was observed on a drm-tip 6.16-rc1 build with the Xe driver in
an SVM test case.

## Which versions are affected by CVE-2025-38515?

It affects 2 products.


Products: Debian Debian Linux, Linux kernel.

## How do I fix CVE-2025-38515?

Apply the vendor's patch.

## Is CVE-2025-38515 being exploited?

There is no known exploitation of CVE-2025-38515 in the wild and no public exploit code.

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- [CVE-2026-24061](https://insights.sbomify.com/CVE-2026-24061/): GNU InetUtils Argument Injection (critical 9.8, exploited in the wild)
- [CVE-2025-39682](https://insights.sbomify.com/CVE-2025-39682/): Linux Kernel Improper Check for Unusual or Exceptional Conditions (critical 9.8, exploited in the wild)
- [CVE-2024-9680](https://insights.sbomify.com/CVE-2024-9680/): Mozilla Firefox Use-After-Free (critical 9.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-38515 and fix it if it is affected.

What it is: CVE-2025-38515 is a medium-severity vulnerability in Debian Debian Linux, published on 16 Aug 2025. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2025-38515 in the wild and no public exploit code.

Affected product: Debian Debian Linux. 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-2025-38515/ (Markdown: https://insights.sbomify.com/CVE-2025-38515/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-38515
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-38515
- OSV: https://osv.dev/vulnerability/CVE-2025-38515

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-38515/
Summaries are generated and may contain mistakes; the official description above is the record.