# CVE-2026-93815: net: au1000: move free_irq out of the close-time spinlocked section

> A sleeping function called in atomic context in the au1000 network driver can cause a kernel panic, leading to denial of service.

- **Severity:** Not scored
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 24 Sep 2026
- **Updated:** 3 Oct 2026
- **Also known as:** AZL-103595, BELL-CVE-2026-93815, DEBIAN-CVE-2026-93815, GHSA-xvh7-3cp2-m6qq, UBUNTU-CVE-2026-93815

## What is CVE-2026-93815?

CVE-2026-93815 is a denial of service vulnerability in Linux, published on 24 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:

net: au1000: move free_irq out of the close-time spinlocked section

au1000_close() calls free_irq() while aup->lock is still held with
spin_lock_irqsave(). free_irq() can sleep because it takes the IRQ
descriptor request mutex, so it does not belong inside the close-time
spinlocked section.

This was found by our static analysis tool and then confirmed by manual
review of the in-tree au1000_close() .ndo_stop path. The reviewed path
keeps aup->lock held across the MAC reset, queue stop and
free_irq(dev->irq, dev).

A directed runtime validation kept that ndo_stop carrier and the same
free_irq(dev->irq, dev) operation under the driver lock. Lockdep reported
"BUG: sleeping function called from invalid context" and "Invalid wait
context" while free_irq() was taking desc->request_mutex, with
au1000_close() and free_irq() on the stack.

Drop aup->lock before freeing the IRQ. The protected close-time work still
stops the device and queue before IRQ teardown, but the sleepable IRQ core
path now runs outside the spinlocked section.

## Which versions are affected by CVE-2026-93815?


## How do I fix CVE-2026-93815?

Apply the vendor's patch.

## Is CVE-2026-93815 being exploited?

There is no known exploitation of CVE-2026-93815 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-93815 and fix it if it is affected.

What it is: CVE-2026-93815 is a denial of service vulnerability in Linux, published on 24 Sep 2026. 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-2026-93815 in the wild and no public exploit code.

Affected product: 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-2026-93815/ (Markdown: https://insights.sbomify.com/CVE-2026-93815/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-93815
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-93815
- OSV: https://osv.dev/vulnerability/CVE-2026-93815

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-93815/
Summaries are generated and may contain mistakes; the official description above is the record.