Revert "sctp: do not disconnect or do anything if size is zero."
Revert "sctp: do not disconnect or do anything if size is zero."

This reverts commit 3386d648b982f99734af351ff9d0f2fc20c9d754.

lscube/feng,winlinvip/feng,lscube/feng,winlinvip/feng,lscube/feng,winlinvip/feng