# DF-2470 -- Infinite loop in isp response-queue pointer update (target mode)

Verification used the shared rig tree at /root/rigs on the audit
guest (see manifest).  The rig for this finding: dfv_ispt  (rig.c = harness,
gen.sh = verbatim extractor, dfv_*_extract.h = generated production text).
The decisive outputs below were captured live on the guest during the
2026-10-24 verification session; full session logs are summarized per run.


## Build
    sh build.sh            # extracts verbatim driver text + builds the KLD

## Run (guest, root)
    kldload ./dfv_rig.ko
kldload dfv_ispt.ko; sysctl kern.dfv_ispt_run=2; sleep 4; sysctl -n kern.dfv_ispt_status

## Expected
run.log: watchdog - dispatch thread STILL INSIDE isp_intr response loop after 3s, done=0; fixed run: DF2470 loop EXITED immediately.

## Fix validation
fix.diff converts the while loop to a single guarded advance; fixed rig run exits immediately.

Verdict: reproduced / impact=denial_of_service (see verdict.json, VERDICT.md)