Linux Kernel GuC Submission Request Reference Counting Vulnerability

A vulnerability in the Linux kernel's handling of request reference counting during error capture and debugfs dumping has been addressed. This issue arose when GuC support was integrated into error capture, disrupting the proper reference counting of request objects. The vulnerability affects the Intel Graphics Driver, specifically in the context of GuC submission management. The problem was exacerbated by the fact that the code responsible for dumping engine state to debugfs did not previously obtain an explicit reference, leading to potential null pointer dereferences and request leaks. The vulnerability has been resolved by standardizing the reference counting process, ensuring that it is consistently applied regardless of the submission model.

Impact

The vulnerability could lead to improper request management, causing null pointer dereferences and memory leaks by failing to correctly reference or release request objects during error handling and state dumping processes.