node-nmap (the vendored library, not our code) treats ANY stderr
output from the nmap binary as a fatal scan error -- including nmap's
own harmless RTT-calibration warning ("RTTVAR has grown to over N
seconds, decreasing to M"), which it prints *during* a scan that goes
on to complete normally. That meant a real, successful scan (valid XML
already sitting in the library's rawData) got discarded and reported
as a failed run with zero hosts discovered -- not just log noise as
initially assumed.
Recover in our own plugin code by detecting this specific known-benign
message and manually re-running node-nmap's own XML-parse-then-complete
path when there's actually output to parse. A genuine parse failure or
any other error message still rejects exactly as before -- this only
widens the recovery path.
wmantly
e313697bfd