Linux Kernel AMDGPU VCN No User Fence Vulnerability

A vulnerability in the Linux kernel's AMDGPU VCN 4.0.3 encoder and decoder rings has been addressed. These rings do not support 64-bit user fence writes, which can lead to issues when command submissions include user fences. The vulnerability arises because the VCN 4.0.3 encoding ring rejects command submissions that use user fences, creating a potential disruption in processing.

Impact

The vulnerability could cause command submissions to be rejected, disrupting the normal operation of applications relying on VCN 4.0.3 encoding and decoding.

Reproduction

The vulnerability can be reproduced by attempting to submit command streams (CS) to the VCN 4.0.3 encoder or decoder rings using 64-bit user fences. The rings will reject the submission due to the unsupported user fence writes.

Remediation

Users can update to the latest version of the Linux kernel where this vulnerability has been fixed. Instructions for downloading the patched version are available on the official Linux kernel website.