This fixes the memory handling of the linger, accept_filter, and
tcp_function_set socket options.

lksctp-tools has supported sctp_sendv and sctp_recvv.

Signed-off-by: Jianwen Ji <jijianwen@gmail.com>

The assert() calls clarify and ensure which thread the functions
is allowed to run in.

When tearing down a TCP connection, try injecting a RST segment
by pretending to peer has received the last packet as an out of
the blue packet.

Before fix:
   sctp_primary_addr.pkt:13: runtime error in setsockopt call: Expected result 0 but got -1 with errno 22 (Invalid argument)

After fix:
   test passed both on Linux x86_64 and ppc64le

Signed-off-by: Jianwen Ji <jijianwen@gmail.com>

Signed-off-by: jijianwen <jijianwen@localhost.localdomain>