Fix crash when receiving unregistered remotes

serial_link/protocol/transport.c

@@ -71,22 +71,24 @@ void add_remote_objects(remote_object_t** _remote_objects, uint32_t _num_remote_
 
 void transport_recv_frame(uint8_t from, uint8_t* data, uint16_t size) {
     uint8_t id = data[size-1];
-    remote_object_t* obj = remote_objects[id];
-    uint8_t* start;
-    if (obj->object_type == MASTER_TO_ALL_SLAVES) {
-        start = obj->buffer + LOCAL_OBJECT_SIZE(obj->object_size);
-    }
-    else if(obj->object_type == SLAVE_TO_MASTER) {
-        start = obj->buffer + LOCAL_OBJECT_SIZE(obj->object_size);
-        start += (from - 1) * REMOTE_OBJECT_SIZE(obj->object_size);
-    }
-    else {
-        start = obj->buffer + NUM_SLAVES * LOCAL_OBJECT_SIZE(obj->object_size);
+    if (id < num_remote_objects) {
+        remote_object_t* obj = remote_objects[id];
+        uint8_t* start;
+        if (obj->object_type == MASTER_TO_ALL_SLAVES) {
+            start = obj->buffer + LOCAL_OBJECT_SIZE(obj->object_size);
+        }
+        else if(obj->object_type == SLAVE_TO_MASTER) {
+            start = obj->buffer + LOCAL_OBJECT_SIZE(obj->object_size);
+            start += (from - 1) * REMOTE_OBJECT_SIZE(obj->object_size);
+        }
+        else {
+            start = obj->buffer + NUM_SLAVES * LOCAL_OBJECT_SIZE(obj->object_size);
+        }
+        triple_buffer_object_t* tb = (triple_buffer_object_t*)start;
+        void* ptr = triple_buffer_begin_write_internal(obj->object_size, tb);
+        memcpy(ptr, data, size -1);
+        triple_buffer_end_write_internal(tb);
     }
-    triple_buffer_object_t* tb = (triple_buffer_object_t*)start;
-    void* ptr = triple_buffer_begin_write_internal(obj->object_size, tb);
-    memcpy(ptr, data, size -1);
-    triple_buffer_end_write_internal(tb);
 }
 
 void update_transport(void) {