Executive brief
A vulnerability was identified in the Linux kernel's AMD GPU driver specifically affecting JPEG hardware acceleration. The issue stems from the driver attempting to use a synchronization feature (user fences) that the hardware does not support. This could lead to unpredictable system behavior or stability issues when processing JPEG media.
Technical details
A vulnerability in the Linux kernel's DRM AMDGPU driver exists because the JPEG v5.3.0 ring does not support 64-bit user fence writes. Prior to the fix, the driver did not explicitly reject Command Stream (CS) submissions that included user fences for this specific hardware version. An attacker with local access could potentially trigger undefined behavior or kernel instability by submitting malformed CS requests. The fix involves setting the 'no_user_fence' flag to true in the jpeg_v5_3_0_dec_ring_vm_funcs structure to ensure such submissions are rejected.
Affected products
- Linux Linux Kernel 7.0, 7.1
Timeline
- 2026-07-19: disclosed
- 2026-07-19: advisory