# CVE-2025-40108: serial: qcom-geni: Fix blocked task

> A regression in the Qualcomm GENI serial driver causes system hangs during boot, resulting in a 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:** 9 Nov 2025
- **Updated:** 11 May 2026
- **Also known as:** BELL-CVE-2025-40108, GHSA-wqc8-4945-8xxr, UBUNTU-CVE-2025-40108

## What is CVE-2025-40108?

CVE-2025-40108 is a denial of service vulnerability in Linux, published on 9 Nov 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:

serial: qcom-geni: Fix blocked task

Revert commit 1afa70632c39 ("serial: qcom-geni: Enable PM runtime for
serial driver") and its dependent commit 86fa39dd6fb7 ("serial:
qcom-geni: Enable Serial on SA8255p Qualcomm platforms") because the
first one causes regression - hang task on Qualcomm RB1 board (QRB2210)
and unable to use serial at all during normal boot:

  INFO: task kworker/u16:0:12 blocked for more than 42 seconds.
        Not tainted 6.17.0-rc1-00004-g53e760d89498 #9
  "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
  task:kworker/u16:0   state:D stack:0     pid:12    tgid:12    ppid:2      task_flags:0x4208060 flags:0x00000010
  Workqueue: async async_run_entry_fn
  Call trace:
   __switch_to+0xe8/0x1a0 (T)
   __schedule+0x290/0x7c0
   schedule+0x34/0x118
   rpm_resume+0x14c/0x66c
   rpm_resume+0x2a4/0x66c
   rpm_resume+0x2a4/0x66c
   rpm_resume+0x2a4/0x66c
   __pm_runtime_resume+0x50/0x9c
   __driver_probe_device+0x58/0x120
   driver_probe_device+0x3c/0x154
   __driver_attach_async_helper+0x4c/0xc0
   async_run_entry_fn+0x34/0xe0
   process_one_work+0x148/0x290
   worker_thread+0x2c4/0x3e0
   kthread+0x118/0x1c0
   ret_from_fork+0x10/0x20

The issue was reported on 12th of August and was ignored by author of
commits introducing issue for two weeks.  Only after complaining author
produced a fix which did not work, so if original commits cannot be
reliably fixed for 5 weeks, they obviously are buggy and need to be
dropped.

## Which versions are affected by CVE-2025-40108?


## How do I fix CVE-2025-40108?

Apply the vendor's patch.

## Is CVE-2025-40108 being exploited?

There is no known exploitation of CVE-2025-40108 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-40108 and fix it if it is affected.

What it is: CVE-2025-40108 is a denial of service vulnerability in Linux, published on 9 Nov 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-2025-40108 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-2025-40108/ (Markdown: https://insights.sbomify.com/CVE-2025-40108/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-40108
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-40108
- OSV: https://osv.dev/vulnerability/CVE-2025-40108

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-40108/
Summaries are generated and may contain mistakes; the official description above is the record.