# CVE-2026-89592: accel/rocket: fix NULL dereference and integer overflow in rocket_job_push()

> A local attacker can trigger a kernel crash or potentially escalate privileges via integer overflow and NULL dereference in the Rocket accelerator driver.

- **Severity:** Not scored
- **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:** 11 Sep 2026
- **Updated:** 19 Oct 2026
- **Also known as:** BELL-CVE-2026-89592, DEBIAN-CVE-2026-89592, GHSA-37xg-5m8h-6hgw, UBUNTU-CVE-2026-89592

## What is CVE-2026-89592?

CVE-2026-89592 is a vulnerability in Linux, published on 11 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:

accel/rocket: fix NULL dereference and integer overflow in rocket_job_push()

rocket_job_push() allocates a temporary array to hold all input and
output GEM object pointers:

    bos = kvmalloc_array(job->in_bo_count + job->out_bo_count,
                         sizeof(void *), GFP_KERNEL);
    memcpy(bos, job->in_bos, job->in_bo_count * sizeof(void *));
    memcpy(&bos[job->in_bo_count], job->out_bos, ...);

Two bugs exist:

1. Missing NULL check: if kvmalloc_array() fails, bos is NULL and
   the subsequent memcpy() dereferences it, causing a kernel NULL
   pointer dereference.

2. Integer overflow: in_bo_count and out_bo_count are both u32, set
   directly from userspace-supplied in_bo_handle_count and
   out_bo_handle_count with no prior validation. Their sum is computed
   in u32 arithmetic and can wrap to a smaller value, causing the
   allocation count passed to kvmalloc_array() to be smaller than
   intended. Subsequent uses still operate on the original counts when
   copying and locking objects, which may lead to out-of-bounds accesses
   on the temporary array.

Fix by using check_add_overflow() to detect count overflow before the
allocation, and adding a NULL check on the allocation result.

## Which versions are affected by CVE-2026-89592?


## How do I fix CVE-2026-89592?

Apply the vendor's patch.

## Is CVE-2026-89592 being exploited?

There is no known exploitation of CVE-2026-89592 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-89592 and fix it if it is affected.

What it is: CVE-2026-89592 is a vulnerability in Linux, published on 11 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-2026-89592 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-2026-89592/ (Markdown: https://insights.sbomify.com/CVE-2026-89592/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-89592
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-89592
- OSV: https://osv.dev/vulnerability/CVE-2026-89592

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-89592/
Summaries are generated and may contain mistakes; the official description above is the record.