FreeBSD doesn't touch reconfig requests third parameter.

[hoelscher]

If FreeBSD receives a reconfig chunk with three parameters, it processes the first and the secodn parameter correctly. But it doesn't recognises that there is a third one. In Fact that there are only two parameters allowed, this reaction is ok. In my opinion the implementation can send error because only two parameters are allowed
see test
https://github.com/nplab/RFC6525_Testsuite/blob/master/implementation_tests/sctp-sr-i-ip/sctp-sr-i-ip-i-4-1.pkt