CVE-2026-68276 drm/amdgpu/gfx: fix cleaner shader IB buffer overflow

In the Linux kernel, the following vulnerability has been resolved: drm/amdgpu/gfx: fix cleaner shader IB buffer overflow The cleaner shader sysfs path allocates a 16-dword 64 byte IB but incorrectly fills alignmask + 1 dwords. On GFX rings alignmask is 0xff, so the loop wrote 256 dwords into a...