⬢ DragonFlyBSD Kernel Audit
DF-4619 / verdict.json
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{
  "finding_id": "DF-4619",
  "status": "reproduced",
  "reproduced": 1,
  "impact": "dos",
  "confidence": "certain",
  "verdict": "REPRODUCED on the DragonFly guest by compiling the verbatim kernel function bodies (sed-extracted ar5413.c:288-540 from /usr/src) against a faithful ar5413State layout: with an EEPROM-shaped crafted dataset (xpd_mask=0xF, Pmin pattern {0,58,58,58}, overlap 15) the unbounded kk walk at ar5413.c:497/:506/:520 wrote 40 uint16 cells (80 bytes) past pcdacTable[PWR_TABLE_SIZE_2413=128] into the Bank1Data..Bank6Data members of the heap-allocated ar5413State object (intra-object overflow; RF bank scratch corrupted). Exploitation is gated on attacker-supplied AR5413 hardware with crafted EEPROM (physical/supply-chain); realistic ceiling is radio misprogramming/crash, not privilege escalation. Fix validated: with kk<PWR_TABLE_SIZE_2413 guards the overflow is gone (bank canary intact).",
  "exploit_chain": "crafted EEPROM (AR5EPROM_VER5_0/eepMap=2, xpd_mask=0xF, flat-ish curves, Pmin {0,58,58,58}) -> ath attach reads cal dataset -> first channel set invokes ar5413SetPowerTable:577 -> getGainBoundariesAndPdadcsForPowers kk walk exceeds 128 -> pPDADCValues[128..167] overwrite Bank1/2/3/6Data -> corrupted RF banks programmed to the radio at next ar5413SetRfRegs (ar5413.c:249-253) + stale pdadc tail. No uid0 route: hardware-gated, intra-object, clamped 16-bit values.",
  "evidence": "run.log: lines DF-4619 REPRODUCED: ... first clobbered u16 cell 0 bytes past array end, last 79 bytes past; fix_run.log: DF-4619: NO overflow detected after patching; ar5413_harness.c + build.sh show the verbatim extraction from /usr/src.",
  "kernel_refs": [
    "sys/dev/netif/ath/ath_hal/ar5212/ar5413.c:397",
    "sys/dev/netif/ath/ath_hal/ar5212/ar5413.c:495",
    "sys/dev/netif/ath/ath_hal/ar5212/ar5413.c:506",
    "sys/dev/netif/ath/ath_hal/ar5212/ar5413.c:520",
    "sys/dev/netif/ath/ath_hal/ar5212/ar5413.c:531",
    "sys/dev/netif/ath/ath_hal/ar5212/ar5413.c:554",
    "sys/dev/netif/ath/ath_hal/ar5413.c:35",
    "sys/dev/netif/ath/ath_hal/ar5413.c:777",
    "sys/dev/netif/ath/ath_hal/ah_eeprom_v3.h:282",
    "sys/dev/netif/ath/ath_hal/ah_eeprom_v3.c:656"
  ],
  "poc_changes": "harness written from scratch (no seed PoC): sed-extracts ar5413.c:288-540 verbatim at build time on the guest, faithful struct (bank rows 1/1/1/37/3 from ar5212.ini, verified offsets pcdac@72 Bank1@328 vpdI@1524 sizeof 2040), HALASSERT compiled out to mirror release (AH_ASSERT undefined), dataset crafted per ar2413SetupRawDataset/ar2413EepromToRawDataset shapes; spans >=2 chosen to isolate DF-4619 from the independent DF-4622 wrap",
  "attempts": 4,
  "guest_uname": "DragonFly dfbsd 6.5-DEVELOPMENT #0: Thu Jul 2 06:02:54 UTC 2026 root@dfbsd:/usr/obj/usr/src/sys/X86_64_GENERIC x86_64",
  "runtime_sec": 240,
  "guest_dirty": 0,
  "build_cmd": "sh build.sh   (sed -n 288,540p /usr/src/sys/dev/netif/ath/ath_hal/ar5212/ar5413.c > ar5413_extracted.inc; cc -O2 -Wall -o ar5413_harness ar5413_harness.c)",
  "run_cmd": "./ar5413_harness 1",
  "code_hash": "fc8693ed15ae1678c4d1a170d2a138dd392f5a59d49cadbaab442826f4a371c1",
  "fix_status": "fixed",
  "fix_baseline_reproduced": 1,
  "fix_patched_reproduced": 0,
  "fix_kernel_uname": "DragonFly dfbsd 6.5-DEVELOPMENT #0 x86_64 (harness-level validation: patched function bodies re-extracted from pristine+fix.diff copy; kernel-build validation hardware-gated: no AR5413 on guest)",
  "fix_verdict": "fix.diff bounds the three pPDADCValues write loops with kk < PWR_TABLE_SIZE_2413; on the patched extraction mode 1 reports NO overflow detected with the bank canary region intact (baseline reproduced 168-cell walk, 80 bytes past).",
  "fix_evidence": "fix_run.log (PATCHED BUILD OK section): --- mode 1 ... DF-4619: NO overflow detected",
  "notes": "intra-object overflow only (stays inside the 2040-byte ath_hal_malloc allocation); values constrained (pdadc clamps 0/127). Sibling wraps found while isolating this one are filed separately as DF-4620/DF-4622.",
  "recommended_fix": "Bound all three pPDADCValues write loops with kk < PWR_TABLE_SIZE_2413 (see fix.diff)."
}