# DF-1833 - Source Verification

## Verdict: REPRODUCED (source-only confirmation)

**Finding**: sys/dev/powermng/amdpm/amdpm.c:613-622

**Mechanism**: amdpm_bread writes *count=len (slave-supplied, unbounded) at L622. Caller copyouts min(rcount,bcount) from uninitialized char buf[1024] → kernel stack info leak.

**Hardware dependency**: Requires AMD SMBus controller + malicious slave peripheral.

**Fix**: Clamp returned len to 32 (SMBus block max).

## Verification method
Source-only confirmation. The cited code path was traced line-by-line in the
audited sys/ tree. The bug exists exactly as described. This is a HW-gated
driver finding — the vulnerable code path requires specific hardware (GPU,
controller, PHY, TPM, etc.) not present in the QEMU audit guest. Runtime
reproduction on this guest is not possible without the hardware.

## Fix validation
fix.diff authored and applied to guest source. All 40 fixes in this batch
compile cleanly in a single combined kernel build: `make -j6 nativekernel
KERNCONF=X86_64_GENERIC` → rc=0, zero -Werror violations.

**Kernel**: DragonFly 6.5-DEVELOPMENT #0: Thu Jul  2 06:02:54 UTC 2026