MFC r339682:
rip6_input() inp validation after epoch(9) After r335924 rip6_input() needs inp validation to avoid working on FREED inps. Apply the relevant bits from r335497,r335501 (rip_input() change) to the IPv6 counterpart.
PR: 232194
Reviewed by: rgrimes, ae (,hps)
Approved by: re (kib)