CVE-2026-43305: drm/amd/display: Fix mismatched unlock for DMUB HW lock in HWSS fast path

Severity: medium (CVSS 5.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.1% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-05-08 · updated 2026-06-17
Weakness: CWE-667

Description

In the Linux kernel, the following vulnerability has been resolved: drm/amd/display: Fix mismatched unlock for DMUB HW lock in HWSS fast path [Why] The evaluation for whether we need to use the DMUB HW lock isn't the same as whether we need to unlock which results in a hang when the fast path is used for ASIC without FAMS support. [How] Store a flag that indicates whether we should use the lock and use that same flag to specify whether unlocking is needed.

Affected products

Linux kernel: from 6.19 before 6.19.6 — fixed in 6.19.6

How to fix

Upgrade to a fixed version: Linux kernel 6.19.6. Check the vendor advisory for mitigations.

References

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