# CVE-2026-80645: rapidio/tsi721: prevent a bad dereference in tsi721_db_dpc()

> A null pointer dereference in the tsi721 RapidIO driver can cause a kernel crash, requiring a patch to fix the loop logic.

- **Severity:** High 8.1 (`CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/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:** 28 Aug 2026
- **Updated:** 29 Aug 2026
- **Also known as:** BELL-CVE-2026-80645, DEBIAN-CVE-2026-80645, GHSA-fmq3-pjfg-pm48, UBUNTU-CVE-2026-80645

## What is CVE-2026-80645?

CVE-2026-80645 is a high-severity vulnerability in Linux, published on 28 Aug 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:

rapidio/tsi721: prevent a bad dereference in tsi721_db_dpc()

With a list_for_each() loop, if we don't find the item we are looking for
in the list, then the loop exits with the iterator, which is "dbell" in
this loop, pointing to invalid memory.

This code uses the "found" variable to determine if we have found the
doorbell we are looking for or not.  However, the problem that the "found"
variable needs to be set to false at the start of each iteration,
otherwise after the first correct doorbell, then everything is marked as
found.

Reset the "found" to false at the start of the iteration and move the
variable inside the loop.

## Which versions are affected by CVE-2026-80645?


## How do I fix CVE-2026-80645?

Apply the vendor's patch.

## Is CVE-2026-80645 being exploited?

There is no known exploitation of CVE-2026-80645 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-80645 and fix it if it is affected.

What it is: CVE-2026-80645 is a high-severity vulnerability in Linux, published on 28 Aug 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-2026-80645 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-2026-80645/ (Markdown: https://insights.sbomify.com/CVE-2026-80645/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-80645
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-80645
- OSV: https://osv.dev/vulnerability/CVE-2026-80645

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-80645/
Summaries are generated and may contain mistakes; the official description above is the record.