messages: Fix memory leaks in the ssh_packet_global_request callback

BUG: https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=1208

Signed-off-by: Andreas Schneider <asn@cryptomilk.org>

src/messages.c

@@ -1406,6 +1406,7 @@ SSH_PACKET_CALLBACK(ssh_packet_global_request){
                     msg->global_request.bind_port);
             session->common.callbacks->global_request_function(session, msg, session->common.callbacks->userdata);
         } else {
+            SAFE_FREE(request);
             ssh_message_queue(session, msg);
             return rc;
         }
@@ -1426,6 +1427,7 @@ SSH_PACKET_CALLBACK(ssh_packet_global_request){
         if(ssh_callbacks_exists(session->common.callbacks, global_request_function)) {
             session->common.callbacks->global_request_function(session, msg, session->common.callbacks->userdata);
         } else {
+            SAFE_FREE(request);
             ssh_message_queue(session, msg);
             return rc;
         }