In the Linux kernel, the following vulnerability has been resolved:
mptcp: pm: fix ID 0 endp usage after multiple re-creations
'localaddrused' and 'addaddraccepted' are decremented for addresses not related to the initial subflow (ID0), because the source and destination addresses of the initial subflows are known from the beginning: they don't count as "additional local address being used" or "ADD_ADDR being accepted".
It is then required not to increment them when the entrypoint used by the initial subflow is removed and re-added during a connection. Without this modification, this entrypoint cannot be removed and re-added more than once.