CVE-2021-47659: drm/plane: Move range check for format_count earlier

Severity: medium (CVSS 5.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2025-02-26 · updated 2026-06-17

Description

In the Linux kernel, the following vulnerability has been resolved: drm/plane: Move range check for format_count earlier While the check for format_count > 64 in __drm_universal_plane_init() shouldn't be hit (it's a WARN_ON), in its current position it will then leak the plane->format_types array and fail to call drm_mode_object_unregister() leaking the modeset identifier. Move it to the start of the function to avoid allocating those resources in the first place.

Affected products

Linux kernel: from 4.14 before 4.19.247; from 4.20 before 5.4.198; from 5.5 before 5.10.121; from 5.11 before 5.15.46; from 5.16 before 5.17.14; from 5.18 before 5.18.3 — fixed in 4.19.247, 5.10.121, 5.15.46, 5.17.14, 5.18.3, 5.4.198

How to fix

Upgrade to a fixed version: Linux kernel 4.19.247, 5.10.121, 5.15.46, 5.17.14. Check the vendor advisory for mitigations.

References

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