CVE-2026-31562 Linux CVE debrief

Who should care

Linux kernel maintainers, users, and administrators who use the mediatek-drm driver should assess their exposure and apply the provided patches to prevent potential crashes. This includes reviewing and applying patches from the Linux kernel repository, ensuring that the Linux kernel is updated to a version that includes the fix, and monitoring for any potential updates or advisories from the Linux kernel community.

Why it matters

The flaw in the Linux kernel's drm/mediatek driver can cause a system crash during the mediatek-drm probe, potentially leading to a denial of service (DoS). Linux kernel maintainers and users should assess their exposure and apply the provided patches to prevent potential crashes.

• System crash during mediatek-drm probe
• Blocking of all subsequent DRM operations
• Potential denial of service (DoS) due to the crash

Technical summary

The vulnerability is caused by the mtk_dsi structure not being stored inside the driver data before invoking mipi_dsi_host_register, leading to a NULL pointer dereference during the DSI DRM encoder registration process. The issue arises from the mtk_dsi_bind function using dev_get_drvdata to retrieve the mtk_dsi struct. The crash occurs when registering the DSI DRM encoder right after acquiring the mode_config.idr_mutex, blocking all subsequent DRM operations. This can cause a system crash during the mediatek-drm probe, potentially leading to a denial of service (DoS).

Defensive priority

Medium priority for Linux kernel maintainers and users, as the vulnerability can cause a crash during the mediatek-drm probe.

Recommended defensive actions

• Review and apply the provided patches from the Linux kernel repository.
• Ensure that the Linux kernel is updated to a version that includes the fix.
• Monitor for any potential updates or advisories from the Linux kernel community.
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up.
• Review the supplied official advisory or CVE record to validate affected scope, severity, and vendor guidance.
• Plan vendor-supported updates or mitigations through normal change control where exposure is confirmed.
• Check relevant monitoring, detection, and logs for exposed assets that need extra review.

Evidence notes

The issue arises from the mtk_dsi_bind function using dev_get_drvdata to retrieve the mtk_dsi struct. The crash occurs when registering the DSI DRM encoder right after acquiring the mode_config.idr_mutex, blocking all subsequent DRM operations.

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.