The AMDGPU driver in the Linux kernel contains a memory leak that occurs when a user queue is torn down. A reference to the most recent fence is retained in userq->last_fence and is not released during module unload. Because of the missing dma_fence_put() call, the last fence object can remain allocated, leaving objects in the amdgpu_userq_fence slab cache. This leak can lead to kernel memory waste and may trigger a BUG during driver unload as reported in the kernel log.

All Linux kernel builds that include the AMDGPU driver and execute the user queue teardown path are affected. Versions of the kernel prior to the fix (commit 8e051e38a8d45caf6a866d4ff842105b577953bb) are vulnerable. No specific version numbers are provided, but the issue exists in kernels containing the corresponding code before the update.

The EPSS score is below 1%, indicating a very low probability that this flaw is actively exploited. The vulnerability is not listed in the CISA KEV catalog. Exploitation would require local kernel access and the ability to unload or reload the AMDGPU module, a scenario unlikely to be targeted by attackers. Consequently, the overall risk is low, and the flaw is unlikely to be leveraged in a real-world attack.