{
  "finding_id": "DF-4212",
  "status": "untested",
  "reproduced": 0,
  "impact": "none",
  "confidence": "certain",
  "verdict": "mpt_raid_attach takes MPT_LOCK only after mpt_spawn_raid_thread succeeds (mpt_raid.c:290), but the spawn-failure goto cleanup (283-287) reaches MPT_UNLOCK (315) on a lock never acquired -> DragonFly lockmgr panic LK_RELEASE: no lock held (kern_lock.c:768). The other error path (handler registration failure, 292-297) leaks the csa CCB allocated at 288. Both are attach-time error-path defects; hardware-gated (no MPT HBA on guest).",
  "exploit_chain": "",
  "evidence": "findings/poc/DF-4212/VERDICT.md, findings/poc/DF-4212/env.txt (guest pciconf: no triggering hardware), findings/poc/DF-4212/fix.diff",
  "kernel_refs": [
    "sys/dev/disk/mpt/mpt_raid.c:283",
    "sys/dev/disk/mpt/mpt_raid.c:288",
    "sys/dev/disk/mpt/mpt_raid.c:290",
    "sys/dev/disk/mpt/mpt_raid.c:314",
    "sys/dev/disk/mpt/mpt.h:763",
    "sys/kern/kern_lock.c:768"
  ],
  "poc_changes": "no runnable PoC: hardware-gated path absent from the audit guest (env.txt)",
  "attempts": 0,
  "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": 0,
  "guest_dirty": 0,
  "build_cmd": null,
  "run_cmd": null,
  "code_hash": null,
  "notes": "Trigger: kthread_create ENOMEM during mpt(4) attach (boot or kldload under memory pressure).",
  "recommended_fix": "return early on spawn failure (nothing to unwind); free csa on the register-failure path",
  "fix_status": "not_testable",
  "fix_baseline_reproduced": 0,
  "fix_patched_reproduced": 0,
  "fix_verdict": "diff authored and git-apply-verified against the read-only sys/ tree; runtime fix validation impossible without the triggering hardware on the QEMU guest",
  "fix_evidence": "findings/poc/DF-4212/fix.diff (git apply --check passed)"
}