Make sure we can't overflow in connection_ap_handshake_send_resolve

Found by Coverity

ChangeLog

@@ -19,6 +19,8 @@ Changes in version 0.2.2.4-alpha - 2009-??-??
       on 0.2.2.1-alpha.
     - Fix two memory leaks in the error case of
       circuit_build_times_parse_state. Bugfix on 0.2.2.2-alpha.
+    - Make it explicit that we can't overflow in
+      connection_ap_handshake_send_resolve. Bugfix on 0.0.7.1-1.
 
 Changes in version 0.2.2.3-alpha - 2009-09-23
   o Major bugfixes:

src/or/connection_edge.c

@@ -2156,8 +2156,9 @@ connection_ap_handshake_send_resolve(edge_connection_t *ap_conn)
     tor_assert(payload_len <= (int)sizeof(inaddr_buf));
   }
 
-  if (payload_len > RELAY_PAYLOAD_SIZE) {
+  if (payload_len > MAX_SOCKS_ADDR_LEN) {
     /* This should be impossible: we don't accept addresses this big. */
+    /* XXX Should we log a bug here? */
     connection_mark_unattached_ap(ap_conn, END_STREAM_REASON_INTERNAL);
     return -1;
   }