Linux Kernel AMDGPU User Queue Stale Write Pointer Mapping Vulnerability

A vulnerability in the Linux kernel's AMDGPU driver related to user queues has been addressed. The issue involved improper management of write pointer (wptr) object mappings, which could lead to accessing outdated data. This vulnerability was present because the wptr object could be unmapped while a queue was still being created, causing conflicts with other buffer objects at the same address. The problem has been fixed by using the 'drm_exec' function to properly manage locks on the virtual memory root buffer object and the write pointer object buffer object, ensuring that the mapping data is accessed correctly.

Impact

The vulnerability could lead to accessing stale mapping data, potentially causing incorrect behavior in the user queue management.