⬢ DragonFlyBSD Kernel Audit
DF-5348 / manifest.json
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{
  "finding_id": "DF-5348",
  "verdict": "reproduced",
  "impact": "phantom deferred load/callback after bus_dmamap_unload (driver-level write-after-free risk) + leaked bounce-page reservations (DoS)",
  "reproduce": {
    "build": "cd /root/busdmauaf && printf 'KMOD=busdmauaf_t2\\nSRCS=busdmauaf.c\\nCOPTS+=-DPOC_TEST=2\\n\\n.include <bsd.kmod.mk>\\n' > Makefile && make -m /usr/share/mk SYSDIR=/usr/src/sys MAKEOBJDIRPREFIX=/root/obj",
    "run": "kldload ./busdmauaf_t2.ko; sleep 2; dmesg | grep PHANTOM",
    "expected": "baseline: '*** DEFERRED CALLBACK FIRED FOR UNLOADED MAP ***' + 'RESULT=PHANTOM CONFIRMED'; patched kernel: 'RESULT=FAILED', no callback"
  },
  "kernel_refs": [
    "sys/sys/bus_dma.h:313",
    "sys/platform/pc64/x86_64/busdma_machdep.c:1022",
    "sys/platform/pc64/x86_64/busdma_machdep.c:645",
    "sys/platform/pc64/x86_64/busdma_machdep.c:1408",
    "sys/platform/pc64/x86_64/busdma_machdep.c:1445",
    "sys/platform/pc64/x86_64/busdma_machdep.c:1046"
  ],
  "artifacts": [
    "busdmauaf.c", "run.log.baseline", "VERDICT.md", "README.md",
    "fix.diff", "build.log", "env.txt", "manifest.json", "verdict.json"
  ]
}