# CVE-2026-97537: scsi: qla2xxx: Fix queue teardown NULL dma_free and bitmap locking

> A NULL pointer dereference in the qla2xxx SCSI driver during queue teardown 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:** 25 Sep 2026
- **Updated:** 21 Oct 2026
- **Also known as:** AZL-104723, BELL-CVE-2026-97537, DEBIAN-CVE-2026-97537, GHSA-46xm-fghf-r34f, UBUNTU-CVE-2026-97537

## What is CVE-2026-97537?

CVE-2026-97537 is a vulnerability in Linux, published on 25 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:

scsi: qla2xxx: Fix queue teardown NULL dma_free and bitmap locking

qla25xx_free_req_que() and qla25xx_free_rsp_que() have two pre-existing
bugs exposed on the error path of qla25xx_create_{req,rsp}_que():

 1. When dma_alloc_coherent() fails during queue creation, the error
    path calls the free function with req->ring / rsp->ring still NULL
    (from kzalloc).  The unconditional dma_free_coherent() with a NULL
    cpu_addr is undefined behavior and can panic.

 2. The free functions clear req_qid_map / rsp_qid_map under vport_lock,
    but the create functions protect the same bitmaps with mq_lock.
    This provides no mutual exclusion.  Additionally, the create error
    path clears the bit and releases mq_lock before calling the free
    function, creating a window where another thread can allocate the
    same que_id and have its ha->req_q_map entry clobbered by the
    subsequent lockless NULL assignment in the free function.

Fix by:

 - Guarding dma_free_coherent() with a NULL check on the ring pointer.

 - Using mq_lock (the lock held by all creators) in the free functions
   to atomically NULL the map entry and clear the bitmap bit.

 - Removing the now-redundant clear_bit blocks from the create error
   paths since the free functions handle it atomically.

## Which versions are affected by CVE-2026-97537?


## How do I fix CVE-2026-97537?

Apply the vendor's patch.

## Is CVE-2026-97537 being exploited?

There is no known exploitation of CVE-2026-97537 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-97537 and fix it if it is affected.

What it is: CVE-2026-97537 is a vulnerability in Linux, published on 25 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-2026-97537 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-2026-97537/ (Markdown: https://insights.sbomify.com/CVE-2026-97537/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-97537
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-97537
- OSV: https://osv.dev/vulnerability/CVE-2026-97537

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-97537/
Summaries are generated and may contain mistakes; the official description above is the record.