{
  "finding_id": "DF-5306",
  "title": "NULL-deref kernel panic at attach: VC header listing zero streaming interfaces leaves sc->data NULL and uvc_drv_init_video() dereferences it",
  "file": "sys/bus/u4b/uvc/uvc_drv.c",
  "verdict": "reproduced",
  "impact": "panic",
  "confidence": "certain",
  "reproduce": {
    "build": "see build.sh (same KLD harness as DF-5305)",
    "run": "see run.sh (kldload /root/build/uvcharness.ko; sysctl hw.uvcharness=2)",
    "expected": "Fatal trap 12, fault virtual address = 0xa (data->num_altsetting at NULL+10); guest dies at db>"
  },
  "kernel_refs": [
    "sys/bus/u4b/uvc/uvc_drv.c:2109",
    "sys/bus/u4b/uvc/uvc_drv.c:2112",
    "sys/bus/u4b/uvc/uvc_drv.c:1513",
    "sys/bus/u4b/uvc/uvc_drv.c:2731",
    "sys/bus/u4b/uvc/uvc_drv.h:645"
  ],
  "artifacts": [
    "README.md", "VERDICT.md", "uvcharness.c", "Makefile", "build.sh", "run.sh",
    "build.log", "run.log", "fix.log", "panic.txt", "env.txt", "fix.diff",
    "manifest.json", "verdict.json", "code_hash.txt"
  ]
}