CVE-2026-64099

In the Linux kernel, the following vulnerability has been resolved:

drm/v3d: Fix use-after-free of CPU job query arrays on error path

The CPU job ioctls fail label calls kvfree() on cpu_jobs timestamp and performance query arrays after v3d_job_cleanup(), which drops the jobs last reference and frees cpu_job. Reading cpu_job at that point is a use-after-free. Also, on the early v3d_job_init() failure path, it is a NULL dereference, since v3d_job_deallocate() zeroes the local pointer.

In the success path, the arrays are released from the schedulers .free_job callback, but on the error path, they are freed manually, as the job was never pushed to the scheduler. While the success path deals with this correctly, the fail path doesnt.

On top of that, the manual kvfree() calls only free the array storage; they dont drm_syncobj_put() the per-query syncobjs that v3d_timestamp_query_info_free() and v3d_performance_query_info_free() release on the success path. So the same fail path that triggers the use-after-free also leaks one syncobj reference per query.

Unify the CPU job teardown into the CPU jobs kref destructor, mirroring v3d_render_job_free(). The schedulers .free_job slot reverts to the generic v3d_sched_job_free() and the fail label drops the manual kvfree() calls, leaving a single teardown path that is reached from both the scheduler and the ioctl error path. That removes the use-after-free, the NULL dereference, and the syncobj leak by construction.

Affected Software

References

• https://git.kernel.org/stable/c/0f8efc45740b0628a787d1b0be8a0ddabd700625
• https://git.kernel.org/stable/c/69c2a1fec2e7ca25598180816f3bc56e1842eb41
• https://git.kernel.org/stable/c/acd55ea40d03e06f20a9986363019e0e5173990e
• https://git.kernel.org/stable/c/b0fe80c0b9250b35e2211bf3117e7aca814a21b0