dhcp: option refcount overflow when leasequery is enabled leading to dhcpd abort

An integer overflow vulnerability was found in the DHCP server. When the "optioncodehashlookup" function is called from "addoption", it increases the option's "refcount" field. However, there is not a corresponding call to "optiondereference" to decrement the "refcount" field. The "addoption"...