inpcb: update inpcb multipath routing information only on success

The in_pcbconnect_setup() function is not supposed to modify inpcb.
It may be entered with read-only lock via UDP path.  Also at this
point we aren't yet sure that the binding is going to be successful.
Thus, update the multipath routing information only at the end of a
succesful in_pcbconnect().

Fixes:	0c325f53f1

sys/netinet/in_pcb.c

@@ -1121,7 +1121,18 @@ in_pcbconnect(struct inpcb *inp, struct sockaddr_in *sin, struct ucred *cred)
 		else
 			in_pcbinshash(inp);
 	}
+#ifdef ROUTE_MPATH
+	if (CALC_FLOWID_OUTBOUND) {
+		uint32_t hash_val, hash_type;
 
+		hash_val = fib4_calc_software_hash(inp->inp_laddr,
+		    inp->inp_faddr, 0, fport,
+		    inp->inp_socket->so_proto->pr_protocol, &hash_type);
+
+		inp->inp_flowid = hash_val;
+		inp->inp_flowtype = hash_type;
+	}
+#endif
 	if (anonport)
 		inp->inp_flags |= INP_ANONPORT;
 	return (0);
@@ -1377,17 +1388,6 @@ in_pcbconnect_setup(struct inpcb *inp, struct sockaddr_in *sin,
 	lport = *lportp;
 	faddr = sin->sin_addr;
 	fport = sin->sin_port;
-#ifdef ROUTE_MPATH
-	if (CALC_FLOWID_OUTBOUND) {
-		uint32_t hash_val, hash_type;
-
-		hash_val = fib4_calc_software_hash(laddr, faddr, 0, fport,
-		    inp->inp_socket->so_proto->pr_protocol, &hash_type);
-
-		inp->inp_flowid = hash_val;
-		inp->inp_flowtype = hash_type;
-	}
-#endif
 	if (V_connect_inaddr_wild && !CK_STAILQ_EMPTY(&V_in_ifaddrhead)) {
 		/*
 		 * If the destination address is INADDR_ANY,