Executive brief
A synchronization issue was identified in the Linux kernel's AMD GPU driver. This flaw occurs when multiple processes share memory buffers across different graphics processors. An exploit could lead to a system crash or application failure (page fault) when one process moves a shared memory buffer while another is still actively using it.
Technical details
A synchronization vulnerability exists in the amdgpu driver within the amdgpu_dma_buf_move_notify function. The root cause is an incorrect use of synchronization 'tickets' in amdgpu_vm_handle_moved, which causes the kernel to update page tables immediately rather than waiting for active GPU jobs to complete. In multi-GPU environments without P2P PCI support, this race condition allows a buffer object (BO) to be moved while a blit or rendering job is still executing on another GPU, resulting in a page fault. The fix involves ensuring the 'clear=true' path is used in amdgpu_vm_bo_update to properly synchronize with pending command submissions. Patches have been merged into multiple stable branches of the Linux kernel.
Affected products
- Linux Linux Kernel n/a
Timeline
- 2026-02-09: other: Patch authored
- 2026-05-08: advisory: CVE published