# CVE-2026-98313: drm/msm/dp: skip PUSH_IDLE when the link was never enabled

> A missing check in the Linux kernel's MSM DisplayPort driver causes a system reset when disabling a failed link, leading to local 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:** 6 Oct 2026
- **Updated:** 19 Oct 2026
- **Also known as:** AZL-110450, BELL-CVE-2026-98313, DEBIAN-CVE-2026-98313, GHSA-hmwj-x5pc-fh88, UBUNTU-CVE-2026-98313

## What is CVE-2026-98313?

CVE-2026-98313 is a denial of service 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:

drm/msm/dp: skip PUSH_IDLE when the link was never enabled

msm_dp_display_atomic_enable() returns early when link training fails,
leaving ->power_on false and the main link down.
msm_dp_display_atomic_disable() nevertheless writes DP_STATE_CTRL_PUSH_IDLE
and waits for an idle-pattern completion that cannot arrive, so every failed
enable is followed by "PUSH_IDLE pattern timedout".

Every other step of the teardown is already gated on that flag:
msm_dp_display_disable(), called from .atomic_post_disable(), returns early
on !power_on. The PUSH_IDLE write is the only one that is not, so the
controller's runtime-PM reference is then dropped without the link having
been taken down.

On glymur (Snapdragon X2 Elite) the consequence is not a warning. The SoC
does not survive it: TrustZone force-stops the SOCCP and ADSP remote
processors and the machine resets silently about 50 ms later, with no oops
and no panic. On an ASUS Zenbook A16 (UX3607OA), whose eDP panel does not
currently train, this reproduces without any compositor or GPU involvement:

  # eDP enable has already failed with "Failed link training (rc=-104)"
  echo 1 > /sys/class/graphics/fb0/blank

  [535.645455] === marker ===
  [535.694833] qcom_q6v5_pas d00000.remoteproc: fatal error received: \
                 sys_m_smsm.c:512:TZ force stop
  [535.694875] remoteproc remoteproc0: crash detected in soccp: type fatal error
  [535.728857] qcom_q6v5_pas 6800000.remoteproc: fatal error received: \
                 sys_m_smsm.c:783:err fatal notification received from TZ
  <SoC reset>

Gate the PUSH_IDLE write on ->power_on so the disable path is consistent
with the rest of the teardown. With this applied the same sequence is
harmless and the machine stays up; without it, it resets every time.

The unconditional write dates back to the original DP driver
(c943b4948b58 ("drm/msm/dp: add displayPort driver support")), but the
surrounding code has been restructured several times since, so no Fixes:
tag is offered.

Note that the eDP link-training failure that exposes this on the A16 is a
separate problem in the glymur eDP PHY and is reported separately; this
change is about not damaging the machine when training fails, for whatever
reason.

Tested on ASUS Zenbook A16 (UX3607OA), Snapdragon X2 Elite Extreme, on
linux-next next-20260803 and next-20260807. The machine has since been
running next-20260807 with this patch as its daily driver.

Patchwork: https://patchwork.freedesktop.org/patch/745167/

## Which versions are affected by CVE-2026-98313?


## How do I fix CVE-2026-98313?

Apply the vendor's patch.

## Is CVE-2026-98313 being exploited?

There is no known exploitation of CVE-2026-98313 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-98313 and fix it if it is affected.

What it is: CVE-2026-98313 is a denial of service 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-2026-98313 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-2026-98313/ (Markdown: https://insights.sbomify.com/CVE-2026-98313/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-98313
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-98313
- OSV: https://osv.dev/vulnerability/CVE-2026-98313

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-98313/
Summaries are generated and may contain mistakes; the official description above is the record.