DF-3412 / verdict.json
{ "finding_id": "DF-3412", "status": "not_reproduced", "reproduced": 0, "impact": "none", "confidence": "certain", "verdict": "Line-accurate confirmation; no runtime demonstration attempted because the defect is typed away (pf_altq.priority is u_int8_t and pfctl bounds to <=255, so the kernel-side field cannot be negative; fairq_add_queue checks only a->priority >= FAIRQ_MAXPRI at altq_fairq.c:230 before pif_classes[a->priority] is read and WRITTEN, and fairq_class_create only pri > pif_maxpri at :439). Identical family to DF-0444 (rmc_newclass OOB). A future in-kernel caller passing an int priority gets a heap OOB write below pif_classes[]. Fix adds two-sided bounds; compiled in the F40FIX build (ALTQ_FAIRQ in kernel).", "exploit_chain": "", "evidence": "VERDICT.md with path:line citations; run.log where a live demo exists; fix.diff", "kernel_refs": [ "sys/net/altq/altq_fairq.c:230", "sys/net/altq/altq_fairq.c:439" ], "poc_changes": "n/a - typed-away today", "attempts": 0, "guest_uname": "DragonFly dfbsd 6.5-DEVELOPMENT DragonFly 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": 30, "guest_dirty": 0, "build_cmd": "see build.sh", "run_cmd": "see run.sh", "code_hash": null, "notes": "", "recommended_fix": "two-sided priority bound checks in fairq_add_queue (and keep the class_create check two-sided)", "fix_status": "compile_validated", "fix_verdict": "fix.diff applied in the F40FIX verification kernel build (RC=0, zero -Werror errors); no runtime A/B for this item (line-certain hardening)" } |