{
 "finding_id": "DF-3234",
 "status": "not_reproduced",
 "reproduced": 0,
 "impact": "corruption",
 "confidence": "certain",
 "verdict": "Environment not provisionable on this guest: the trigger needs an EXT2_INCOMPAT_64BIT filesystem whose allocation returns blocks above 2^32 (>= 4 TiB at 1K blocks, >= 16 TiB at 4K blocks) - the four EFBIG returns in ext2_balloc fire only there, and each leaks the ext2_alloc result (bitmap bit set, group/free counters moved, i_blocks charged, nothing rolled back, no ext2_blkfree). The defect is line-certain by inspection (contrast the bwrite-failure path at :225 which does call ext2_blkfree), and the guest lacks both the disk space and an ext2 mkfs in base. Fix adds blkfree + unlock before each EFBIG return; compile-validated.",
 "exploit_chain": "",
 "evidence": "VERDICT.md walk over ext2_balloc.c:135-136/:169-170/:215-218/:258-261",
 "kernel_refs": [
  "sys/vfs/ext2fs/ext2_balloc.c:135-136",
  "sys/vfs/ext2fs/ext2_balloc.c:169-170",
  "sys/vfs/ext2fs/ext2_balloc.c:215-218",
  "sys/vfs/ext2fs/ext2_balloc.c:258-261"
 ],
 "poc_changes": "",
 "attempts": 2,
 "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": 60,
 "guest_dirty": 0,
 "build_cmd": "n/a (needs >= 4TiB 64BIT ext2 volume)",
 "run_cmd": "n/a",
 "code_hash": "",
 "notes": "",
 "recommended_fix": "ext2_blkfree + EXT2_UNLOCK before each EFBIG return"
}