CVE-2026-53143

In the Linux kernel, the following vulnerability has been resolved:

drm/amdkfd: Fix buffer overflow in SDMA queue checkpoint/restore on GFX11

The v11 MQD manager incorrectly assigned the CP-compute variants of checkpointmqd/restoremqd for KFDMQDTYPESDMA queues. These functions use sizeof(struct v11computemqd) (2048 bytes) instead of sizeof(struct v11sdma_mqd) (512 bytes), causing a 1536-byte overflow.

During CRIU checkpoint of an SDMA queue on Navi3x: - checkpoint_mqd() reads 2048 bytes from a 512-byte SDMA MQD buffer, leaking 1536 bytes of adjacent GTT memory to userspace

During CRIU restore: - restore_mqd() writes 2048 bytes into a 512-byte SDMA MQD buffer, corrupting 1536 bytes of adjacent GTT memory (often the ring buffer or neighboring MQDs)

This is a copy-paste regression unique to v11. All other ASIC backends (cik, vi, v9, v10, v12) correctly use the SDMA-specific variants.

Add checkpointmqdsdma() and restoremqdsdma() functions that properly handle the smaller v11sdmamqd structure, matching the pattern used in other MQD managers.

(cherry picked from commit 6fa41db7ffdec97d62433adf03b7b9b759af8c2c)