emit MAV_RESULT_DENIED if start/stop item passed to MAV_CMD_MISSION_START

ArduCopter/GCS_Mavlink.cpp

@@ -960,6 +960,10 @@ MAV_RESULT GCS_MAVLINK_Copter::handle_MAV_CMD_DO_CHANGE_SPEED(const mavlink_comm
 #if MODE_AUTO_ENABLED == ENABLED
 MAV_RESULT GCS_MAVLINK_Copter::handle_MAV_CMD_MISSION_START(const mavlink_command_int_t &packet)
 {
+        if (!is_zero(packet.param1) || !is_zero(packet.param2)) {
+            // first-item/last item not supported
+            return MAV_RESULT_DENIED;
+        }
         if (copter.set_mode(Mode::Number::AUTO, ModeReason::GCS_COMMAND)) {
             copter.set_auto_armed(true);
             if (copter.mode_auto.mission.state() != AP_Mission::MISSION_RUNNING) {

ArduPlane/GCS_Mavlink.cpp

@@ -1080,6 +1080,10 @@ MAV_RESULT GCS_MAVLINK_Plane::handle_command_int_packet(const mavlink_command_in
         return MAV_RESULT_FAILED;
 
     case MAV_CMD_MISSION_START:
+        if (!is_zero(packet.param1) || !is_zero(packet.param2)) {
+            // first-item/last item not supported
+            return MAV_RESULT_DENIED;
+        }
         plane.set_mode(plane.mode_auto, ModeReason::GCS_COMMAND);
         return MAV_RESULT_ACCEPTED;
 

ArduSub/GCS_Mavlink.cpp

@@ -542,6 +542,10 @@ MAV_RESULT GCS_MAVLINK_Sub::handle_command_int_packet(const mavlink_command_int_
         return handle_command_int_do_reposition(packet);
 
     case MAV_CMD_MISSION_START:
+        if (!is_zero(packet.param1) || !is_zero(packet.param2)) {
+            // first-item/last item not supported
+            return MAV_RESULT_DENIED;
+        }
         return handle_MAV_CMD_MISSION_START(packet);
 
     case MAV_CMD_NAV_LOITER_UNLIM:

Rover/GCS_Mavlink.cpp

@@ -701,6 +701,10 @@ MAV_RESULT GCS_MAVLINK_Rover::handle_command_int_packet(const mavlink_command_in
                                               packet.param4);
 
     case MAV_CMD_MISSION_START:
+        if (!is_zero(packet.param1) || !is_zero(packet.param2)) {
+            // first-item/last item not supported
+            return MAV_RESULT_DENIED;
+        }
         if (rover.set_mode(rover.mode_auto, ModeReason::GCS_COMMAND)) {
             return MAV_RESULT_ACCEPTED;
         }

Tools/autotest/arducopter.py

@@ -11729,6 +11729,36 @@ def BatteryInternalUseOnly(self):
                 "id": 1
             })
 
+    def MAV_CMD_MISSION_START_p1_p2(self):
+        '''make sure we deny MAV_CMD_MISSION_START if either p1 or p2 non-zero'''
+        self.upload_simple_relhome_mission([
+            (mavutil.mavlink.MAV_CMD_NAV_TAKEOFF, 0, 0, 20),
+        ])
+        self.set_parameters({
+            "AUTO_OPTIONS": 3,
+        })
+        self.change_mode('AUTO')
+        self.wait_ready_to_arm()
+
+        self.run_cmd(
+            mavutil.mavlink.MAV_CMD_MISSION_START,
+            p1=1,
+            want_result=mavutil.mavlink.MAV_RESULT_DENIED,
+        )
+
+        self.run_cmd(
+            mavutil.mavlink.MAV_CMD_MISSION_START,
+            p2=1,
+            want_result=mavutil.mavlink.MAV_RESULT_DENIED,
+        )
+
+        self.run_cmd(
+            mavutil.mavlink.MAV_CMD_MISSION_START,
+            p1=1,
+            p2=1,
+            want_result=mavutil.mavlink.MAV_RESULT_DENIED,
+        )
+
     def tests2b(self):  # this block currently around 9.5mins here
         '''return list of all tests'''
         ret = ([
@@ -11828,6 +11858,7 @@ def tests2b(self):  # this block currently around 9.5mins here
             self.LoggingFormat,
             self.MissionRTLYawBehaviour,
             self.BatteryInternalUseOnly,
+            self.MAV_CMD_MISSION_START_p1_p2,
         ])
         return ret