# CVE-2022-49931: IB/hfi1: Correctly move list in sc_disable()

> A null pointer dereference in the IB/hfi1 driver causes a kernel crash when a link goes down with pending send operations.

- **Severity:** High 8.8 (`CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`)
- **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:** 1 May 2025
- **Updated:** 5 Aug 2026
- **Also known as:** DEBIAN-CVE-2022-49931, GHSA-6vr6-r6mg-9m3f, UBUNTU-CVE-2022-49931

## What is CVE-2022-49931?

CVE-2022-49931 is a high-severity vulnerability in Linux kernel, published on 1 May 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:

IB/hfi1: Correctly move list in sc_disable()

Commit 13bac861952a ("IB/hfi1: Fix abba locking issue with sc_disable()")
incorrectly tries to move a list from one list head to another.  The
result is a kernel crash.

The crash is triggered when a link goes down and there are waiters for a
send to complete.  The following signature is seen:

  BUG: kernel NULL pointer dereference, address: 0000000000000030
  [...]
  Call Trace:
   sc_disable+0x1ba/0x240 [hfi1]
   pio_freeze+0x3d/0x60 [hfi1]
   handle_freeze+0x27/0x1b0 [hfi1]
   process_one_work+0x1b0/0x380
   ? process_one_work+0x380/0x380
   worker_thread+0x30/0x360
   ? process_one_work+0x380/0x380
   kthread+0xd7/0x100
   ? kthread_complete_and_exit+0x20/0x20
   ret_from_fork+0x1f/0x30

The fix is to use the correct call to move the list.

Weakness: CWE-476 (NULL Pointer Dereference)

## Which versions are affected by CVE-2022-49931?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2022-49931?

Apply the vendor's patch.

## Is CVE-2022-49931 being exploited?

There is no known exploitation of CVE-2022-49931 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-2022-49931 and fix it if it is affected.

What it is: CVE-2022-49931 is a high-severity vulnerability in Linux kernel, published on 1 May 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-2022-49931 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-2022-49931/ (Markdown: https://insights.sbomify.com/CVE-2022-49931/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2022-49931
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2022-49931
- OSV: https://osv.dev/vulnerability/CVE-2022-49931

---
From sbomify Insights: https://insights.sbomify.com/CVE-2022-49931/
Summaries are generated and may contain mistakes; the official description above is the record.