summary over 20 rounds per variant:
  A groom 00 ff ff : EADDRNOTAVAIL=20 EINVAL=0 other=0
  B groom 00 00 00 : EADDRNOTAVAIL=0 EINVAL=20 other=0
  C no groom       : EADDRNOTAVAIL=0 EINVAL=20 other=0

RESULT: VULNERABLE -- connect(2) error code is chosen by heap bytes OUTSIDE the supplied sockaddr length (read before sa_len validation).
EXIT=0
  A groom 00 ff ff : EADDRNOTAVAIL=20 EINVAL=0 other=0
  B groom 00 00 00 : EADDRNOTAVAIL=0 EINVAL=20 other=0
  C no groom       : EADDRNOTAVAIL=0 EINVAL=20 other=0

RESULT: VULNERABLE -- connect(2) error code is chosen by heap bytes OUTSIDE the supplied sockaddr length (read before sa_len validation).