# CVE-2026-98343: dmaengine: fix use-after-free in dma_chan_put() and dma_release_channel()

> A use-after-free in the Linux kernel DMA engine allows local attackers to execute arbitrary code or escalate privileges.

- **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:** 6 Oct 2026
- **Updated:** 19 Oct 2026
- **Also known as:** AZL-106095, BELL-CVE-2026-98343, DEBIAN-CVE-2026-98343, GHSA-rw66-9h9x-4vjf, UBUNTU-CVE-2026-98343

## What is CVE-2026-98343?

CVE-2026-98343 is an use after free vulnerability in Linux, published on 6 Oct 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:

dmaengine: fix use-after-free in dma_chan_put() and dma_release_channel()

When dma_device_put() drops the last reference on chan->device->ref,
dma_device_release() runs and may free the dma_device along with its
channels.

dma_chan_put() then still reads chan->device->owner via
dma_chan_to_owner() for the trailing module_put(). KASAN catches it:

	slab-use-after-free in dma_chan_put+0x3e6/0x4c0
	Read of size 8 by task insmod/6319
	Freed by task 6319:
	  kfree+0x225/0x470
	  dma_chan_put+0x395/0x4c0
	  dmaengine_put+0xf8/0x160

Cache the module owner in dma_chan_put() before the put so the trailing
module_put() does not need chan->device.

## Which versions are affected by CVE-2026-98343?


## How do I fix CVE-2026-98343?

Apply the vendor's patch.

## Is CVE-2026-98343 being exploited?

There is no known exploitation of CVE-2026-98343 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-98343 and fix it if it is affected.

What it is: CVE-2026-98343 is an use after free vulnerability in Linux, published on 6 Oct 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-2026-98343 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-2026-98343/ (Markdown: https://insights.sbomify.com/CVE-2026-98343/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-98343
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-98343
- OSV: https://osv.dev/vulnerability/CVE-2026-98343

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-98343/
Summaries are generated and may contain mistakes; the official description above is the record.