CVE-2024-42263

What it actually does

Missing drm_syncobj_put calls in the v3d timestamp extension cause drm_syncobj references to be leaked when userspace memory fetch fails inside the main loop.

Why it matters to the business

Systems using the v3d DRM driver may experience gradual memory exhaustion or denial of service after repeated triggering of the affected code path, increasing operational risk for graphics workloads on affected kernels.

How an attack unfolds

A local attacker invokes the timestamp extension ioctl, forces a userspace memory copy failure during iteration, and leaves accumulated drm_syncobj references unreleased, steadily consuming kernel memory.

How to fix it

Update the Linux kernel to a version containing commit 9b5033ee2c5af6d1135a403df32d219ab57e55f9 or later; apply the exported common cleanup helper for drm_syncobj references.

How to confirm the fix worked

Confirm the presence of the cleanup helper call after the memory-fetch error path in the v3d timestamp extension code; verify the fixed commit hash is present in the running kernel tree.

Typical attack path

1. Obtain local user access on a system with the v3d DRM driver loaded
2. Trigger the timestamp extension ioctl path
3. Cause the userspace memory fetch to fail inside the main loop
4. Repeat to accumulate unreleased drm_syncobj objects

How to detect it

Review kernel logs for repeated failures inside v3d timestamp handling; inspect memory usage trends on systems with the v3d driver active; look for processes invoking DRM ioctls immediately before memory spikes.

What your security team should do

• Prioritize kernel upgrades on any hosts exposing the v3d DRM driver
• Monitor for memory pressure or OOM events correlated with graphics workloads
• Restrict local user access to graphics devices until patches are applied