⬢ DragonFlyBSD Kernel Audit
DF-4369 / manifest.json
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{
  "finding_id": "DF-4369",
  "verdict": "not_reproduced",
  "impact": "none",
  "reproduced": 0,
  "confidence": "likely",
  "summary": "hpt_timeout() races os_cmddone(): callout_stop() does not interlock against an in-progress timeout, so the 20s deadline firing on another CPU while the command completes reads pCmd->priv after ldm_free_cmds() freed it; if the PCOMMAND is recycled (flush: priv=&done on the kernel stack; internal LDM commands: NULL/other), ext->vbus_ext resolves to stack/garbage and ldm_reset_vbus() panics. Hardware-gated: requires a RocketRAID 27xx controller; audit guest has none (dmesg: 'hpt27xx: no controller detected.'), so the race could not be executed. Static proof chain in race_proof.txt / VERDICT.md.",
  "exploit_chain": "",
  "kernel_refs": [
    "sys/dev/raid/hpt27xx/hpt27xx_osm_bsd.c:411",
    "sys/dev/raid/hpt27xx/hpt27xx_osm_bsd.c:414",
    "sys/dev/raid/hpt27xx/hpt27xx_osm_bsd.c:418",
    "sys/dev/raid/hpt27xx/hpt27xx_osm_bsd.c:421",
    "sys/dev/raid/hpt27xx/hpt27xx_osm_bsd.c:428",
    "sys/dev/raid/hpt27xx/hpt27xx_osm_bsd.c:463",
    "sys/dev/raid/hpt27xx/hpt27xx_osm_bsd.c:464",
    "sys/dev/raid/hpt27xx/hpt27xx_osm_bsd.c:530",
    "sys/dev/raid/hpt27xx/hpt27xx_osm_bsd.c:730",
    "sys/dev/raid/hpt27xx/hpt27xx_osm_bsd.c:303",
    "sys/dev/raid/hpt27xx/os_bsd.h:190",
    "sys/dev/raid/hpt27xx/him.h:417",
    "sys/kern/kern_timeout.c:1087"
  ],
  "artifacts": [
    "README.md",
    "VERDICT.md",
    "race_proof.txt",
    "verify_env.sh",
    "run.sh",
    "run.log",
    "env.txt",
    "fix.diff",
    "manifest.json",
    "verdict.json"
  ],
  "reproduce": {
    "build": "nothing to build — driver compiled into X86_64_GENERIC (sys/config/X86_64_GENERIC:117)",
    "run": "./run.sh   (guest probe: pciconf -l; kldstat -v; ls /dev/hpt27xx; dmesg | grep hpt)",
    "expected": "On real RocketRAID 27xx hardware under SMP: command completing at the same instant its 20s HPT_OSM_TIMEOUT expires causes hpt_timeout() to read pCmd->priv after ldm_free_cmds() freed it; recycled command blocks (flush priv=&done stack at :303) turn this into ldm_reset_vbus(wild pointer) -> fatal trap. On this guest: 'hpt27xx: no controller detected.' — paths unreachable."
  },
  "fix_status": "not_testable",
  "fix_baseline_reproduced": 0,
  "fix_patched_reproduced": 0,
  "fix_verdict": "fix.diff authored (hpt_timeout takes the recursive vbus lock and re-validates pCmd->priv==ext and pCmd->done==os_cmddone before resetting). Cannot be build-validated on the audit guest: no HighPoint controller, and reproducing the baseline race itself requires one. callout_stop_sync() was deliberately avoided — os_cmddone runs in interrupt context while hpt_timeout needs the same vbus lock, so a synchronizing stop would deadlock.",
  "fix_evidence": "fix.diff; VERDICT.md 'Fix' section"
}