⬢ DragonFlyBSD Kernel Audit
DF-5787 / manifest.json
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{
  "finding_id": "DF-5787",
  "title": "vfs_bio.c: stale b_bio1.bio_flags survive buffer-cache recycling (no kernel-side BIO_DONE hygiene)",
  "verdict": "reproduced",
  "impact": "panic",
  "confidence": "certain",
  "severity": "Low",
  "reproduce": {
    "build": "guest: mkdir -p /root/biopoison; cp biopoison.c Makefile; make   (SYSDIR=/usr/src/sys)",
    "run": "guest: kldload /root/biopoison/biopoison.ko ; observe serial console (dfbsd-qemu/vm.sh log)",
    "expected": "control case: 'bread returned 0 (no panic)'; poison case: panic: assertion \"(bio->bio_flags & BIO_DONE) == 0\" failed in vn_strategy at /usr/src/sys/kern/vfs_bio.c:3385 (baseline kernel); with fix.diff kernel: both cases return 0, no panic"
  },
  "kernel_refs": [
    "sys/kern/vfs_bio.c:2095",
    "sys/kern/vfs_bio.c:747",
    "sys/kern/vfs_bio.c:919",
    "sys/kern/vfs_bio.c:989",
    "sys/kern/vfs_bio.c:883",
    "sys/kern/vfs_bio.c:3261",
    "sys/kern/vfs_bio.c:3385"
  ],
  "artifacts": [
    "README.md", "VERDICT.md", "biopoison.c", "Makefile", "build.sh", "run.sh",
    "build.log", "run.log", "panic.txt", "fix_run.log", "fix_build.log",
    "env.txt", "fix.diff", "verdict.json", "manifest.json"
  ]
}