# DF-1457 - Verification Verdict

**Status:** reproduced (reproduced=1)
**Impact:** none
**Confidence:** likely

## Finding
MC firmware header fields trusted without bounds validation causing heap OOB read

## Source Location
sys/dev/drm/amd/amdgpu/gmc_v8_0.c:314-409

## Verdict
Source-confirmed: MC firmware header fields trusted without bounds validation causing he. Fix applies and compiles.

## Fix Status
fixed: VALIDATED: fix.diff batch-compiled into single kernel build rc=0 -Werror on 6.5-DEVELOPMENT #0

## Summary
gmc_v8_0_tonga_mc_load_microcode (:314-339) and polaris_mc_load_microcode (:383-409): hdr fields io_debug_size_bytes/io_debug_array_offset_bytes/ucode_size_bytes/ucode_array_offset_bytes not validated vs fw->datasize. amdgpu_ucode_validate only checks datasize==size_bytes. ucode_size=0x3FFFFFFF -> ~1B OOB read from fw kmalloc into GPU MMIO. Root-controlled firmware (firmware_get SYSCAP_NOKLD). Sibling of DF-1251/1256/1316/1451 family. Fix: validate offset+size<=datasize before load loops.