CVE-2026-31571: drm/i915: Unlink NV12 planes earlier

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: 2026-04-24 · updated 2026-06-17

Description

In the Linux kernel, the following vulnerability has been resolved: drm/i915: Unlink NV12 planes earlier unlink_nv12_plane() will clobber parts of the plane state potentially already set up by plane_atomic_check(), so we must make sure not to call the two in the wrong order. The problem happens when a plane previously selected as a Y plane is now configured as a normal plane by user space. plane_atomic_check() will first compute the proper plane state based on the userspace request, and unlink_nv12_plane() later clears some of the state. This used to work on account of unlink_nv12_plane() skipping the state clearing based on the plane visibility. But I removed that check, thinking it was an impossible situation. Now when that situation happens unlink_nv12_plane() will just WARN and proceed to clobber the state. Rather than reverting to the old way of doing things, I think it's more clear if we unlink the NV12 planes before we even compute the new plane state. (cherry picked from commit 017ecd04985573eeeb0745fa2c23896fb22ee0cc)

Affected products

Linux kernel: from 6.15.1 before 6.18.21; from 6.19 before 6.19.11; 6.15, 7.0-rc1, 7.0-rc2, 7.0-rc3, 7.0-rc4, 7.0-rc5 (+2) — fixed in 6.18.21, 6.19.11

How to fix

Upgrade to a fixed version: Linux kernel 6.18.21, 6.19.11. Check the vendor advisory for mitigations.

References

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