# DF-1808 - Source Verification

## Verdict: REPRODUCED (source-only confirmation)

**Finding**: sys/dev/netif/ath/ath_hal/ar5211/ar5211_misc.c:680-682

**Mechanism**: HAL_DIAG_RFGAIN copies entire GAIN_VALUES struct including currStep kernel rodata pointer to userland via SIOCGATHDIAG. No priv check on the path.

**Hardware dependency**: Requires ATH_DIAGAPI (not in GENERIC) + ath(4) hardware.

**Fix**: Zero currStep pointer before export in HAL_DIAG_RFGAIN case.

## 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