fix(various): Fix hardfaults when running out of memory (nullptr check) (#26516)

* Fix hardfault in mavlink stream strcpy

* prevent more OOM hardfaults

* revert mavlink fallback

* delete _interpreter in mc_nn_control module

* fix build

---------

Co-authored-by: jonas <jonas.perolini@rigi.tech>
Co-authored-by: Julian Oes <julian@oes.ch>

src/modules/gyro_fft/GyroFFT.hpp

@@ -111,7 +111,8 @@ private:
 		return (_gyro_data_buffer_x && _gyro_data_buffer_y && _gyro_data_buffer_z
 			&& _hanning_window
 			&& _fft_input_buffer
-			&& _fft_outupt_buffer);
+			&& _fft_outupt_buffer
+			&& _peak_magnitudes_all);
 	}
 
 	uORB::Publication<sensor_gyro_fft_s> _sensor_gyro_fft_pub{ORB_ID(sensor_gyro_fft)};

src/modules/mavlink/mavlink_command_sender.cpp

@@ -52,11 +52,19 @@ void MavlinkCommandSender::initialize()
 
 	if (_instance == nullptr) {
 		_instance = new MavlinkCommandSender();
+
+		if (_instance == nullptr) {
+			PX4_ERR("MavlinkCommandSender alloc failed");
+		}
 	}
 }
 
 MavlinkCommandSender &MavlinkCommandSender::instance()
 {
+	if (_instance == nullptr) {
+		initialize();
+	}
+
 	return *_instance;
 }
 

src/modules/mavlink/mavlink_main.cpp

@@ -1307,6 +1307,12 @@ Mavlink::configure_stream_threadsafe(const char *stream_name, const float rate)
 		/* copy stream name */
 		unsigned n = strlen(stream_name) + 1;
 		char *s = new char[n];
+
+		if (s == nullptr) {
+			PX4_ERR("stream allocation failed");
+			return;
+		}
+
 		strcpy(s, stream_name);
 
 		/* set subscription task */
@@ -2622,7 +2628,7 @@ Mavlink::task_main(int argc, char *argv[])
 
 	_receiver.stop();
 
-	delete _subscribe_to_stream;
+	delete[] _subscribe_to_stream;
 	_subscribe_to_stream = nullptr;
 
 	/* delete streams */

src/modules/mavlink/mavlink_parameters.cpp

@@ -716,6 +716,12 @@ void MavlinkParametersManager::enque_uavcan_request(uavcan_parameter_request_s *
 	}
 
 	_uavcan_open_request_list_item *new_reqest = new _uavcan_open_request_list_item;
+
+	if (new_reqest == nullptr) {
+		PX4_ERR("uavcan request alloc failed");
+		return;
+	}
+
 	new_reqest->req = *req;
 	new_reqest->next = nullptr;
 

src/modules/mc_nn_control/mc_nn_control.cpp

@@ -72,6 +72,10 @@ MulticopterNeuralNetworkControl::MulticopterNeuralNetworkControl() :
 
 MulticopterNeuralNetworkControl::~MulticopterNeuralNetworkControl()
 {
+	delete _interpreter;
+	_interpreter = nullptr;
+	_input_tensor = nullptr;
+	_output_tensor = nullptr;
 	perf_free(_loop_perf);
 }
 
@@ -88,6 +92,14 @@ bool MulticopterNeuralNetworkControl::init()
 
 int MulticopterNeuralNetworkControl::InitializeNetwork()
 {
+	if (_interpreter != nullptr) {
+		delete _interpreter;
+		_interpreter = nullptr;
+	}
+
+	_input_tensor = nullptr;
+	_output_tensor = nullptr;
+
 	// Initialize the neural network
 	const tflite::Model *control_model = ::tflite::GetModel(control_net_tflite);
 
@@ -103,11 +115,18 @@ int MulticopterNeuralNetworkControl::InitializeNetwork()
 	static uint8_t tensor_arena[kTensorArenaSize];
 	_interpreter = new tflite::MicroInterpreter(control_model, resolver, tensor_arena, kTensorArenaSize);
 
+	if (_interpreter == nullptr) {
+		PX4_ERR("interpreter alloc failed");
+		return -1;
+	}
+
 	// Allocate memory for the model's tensors
 	TfLiteStatus allocate_status = _interpreter->AllocateTensors();
 
 	if (allocate_status != kTfLiteOk) {
 		PX4_ERR("AllocateTensors() failed");
+		delete _interpreter;
+		_interpreter = nullptr;
 		return -1;
 	}
 
@@ -115,6 +134,8 @@ int MulticopterNeuralNetworkControl::InitializeNetwork()
 
 	if (_input_tensor == nullptr) {
 		PX4_ERR("Input tensor is null");
+		delete _interpreter;
+		_interpreter = nullptr;
 		return -1;
 	}
 

src/modules/mc_nn_control/mc_nn_control.hpp

@@ -149,9 +149,9 @@ private:
 	uint8 _mode_request_id{231}; //Random value
 	int8 _arming_check_id{-1};
 	int8 _mode_id{-1};
-	tflite::MicroInterpreter *_interpreter;
-	TfLiteTensor *_input_tensor;
-	TfLiteTensor *_output_tensor;
+	tflite::MicroInterpreter *_interpreter{nullptr};
+	TfLiteTensor *_input_tensor{nullptr};
+	TfLiteTensor *_output_tensor{nullptr};
 	float _input_data[15];
 	trajectory_setpoint_s _trajectory_setpoint;
 	vehicle_angular_velocity_s _angular_velocity;

src/modules/replay/Replay.cpp

@@ -527,6 +527,12 @@ Replay::readAndAddSubscription(std::ifstream &file, uint16_t msg_size)
 	}
 
 	Subscription *subscription = new Subscription();
+
+	if (subscription == nullptr) {
+		delete compat;
+		return ReadAndAndAddSubResult::kFailure;
+	}
+
 	subscription->orb_meta = orb_meta;
 	subscription->multi_id = multi_id;
 	subscription->compat = compat;

src/modules/sensors/data_validator/DataValidatorGroup.cpp

@@ -54,6 +54,11 @@ DataValidatorGroup::DataValidatorGroup(unsigned siblings)
 	for (unsigned i = 0; i < siblings; i++) {
 		next = new DataValidator();
 
+		if (next == nullptr) {
+			PX4_ERR("alloc failed");
+			break;
+		}
+
 		if (i == 0) {
 			_first = next;
 
@@ -64,7 +69,7 @@ DataValidatorGroup::DataValidatorGroup(unsigned siblings)
 		prev = next;
 	}
 
-	_last = next;
+	_last = prev;
 
 	if (_first) {
 		_timeout_interval_us = _first->get_timeout();
@@ -89,8 +94,14 @@ DataValidator *DataValidatorGroup::add_new_validator()
 		return nullptr;
 	}
 
-	_last->setSibling(validator);
-	_last = validator;
+	if (_last) {
+		_last->setSibling(validator);
+		_last = validator;
+
+	} else {
+		_first = _last = validator;
+	}
+
 	_last->set_timeout(_timeout_interval_us);
 	return _last;
 }

src/modules/simulation/simulator_mavlink/SimulatorMavlink.cpp

@@ -483,6 +483,11 @@ void SimulatorMavlink::handle_message_hil_gps(const mavlink_message_t *msg)
 
 			if (_sensor_gps_pubs[i] == nullptr) {
 				_sensor_gps_pubs[i] = new uORB::PublicationMulti<sensor_gps_s> {ORB_ID(sensor_gps)};
+
+				if (_sensor_gps_pubs[i] == nullptr) {
+					break;
+				}
+
 				_gps_ids[i] = hil_gps.id;
 
 				device::Device::DeviceId device_id;
@@ -1588,6 +1593,11 @@ int SimulatorMavlink::publish_distance_topic(const mavlink_distance_sensor_t *di
 
 		if (_dist_pubs[i] == nullptr) {
 			_dist_pubs[i] = new uORB::PublicationMulti<distance_sensor_s> {ORB_ID(distance_sensor)};
+
+			if (_dist_pubs[i] == nullptr) {
+				break;
+			}
+
 			_dist_sensor_ids[i] = dist.device_id;
 			_dist_pubs[i]->publish(dist);
 			break;

src/modules/uxrce_dds_client/uxrce_dds_client.cpp

@@ -884,12 +884,12 @@ bool UxrceddsClient::setBaudrate(int fd, unsigned baud)
 
 bool UxrceddsClient::add_replier(SrvBase *replier)
 {
-	if (_num_of_repliers < MAX_NUM_REPLIERS) {
-		_repliers[_num_of_repliers] = replier;
-
-		_num_of_repliers++;
+	if (replier == nullptr || _num_of_repliers >= MAX_NUM_REPLIERS) {
+		return true;
 	}
 
+	_repliers[_num_of_repliers] = replier;
+	_num_of_repliers++;
 	return false;
 }
 

src/modules/vtol_att_control/vtol_att_control_main.cpp

@@ -79,6 +79,12 @@ VtolAttitudeControl::VtolAttitudeControl() :
 		exit_and_cleanup(desc);
 	}
 
+	if (_vtol_type == nullptr) {
+		PX4_ERR("vtol type allocation failed");
+		exit_and_cleanup(desc);
+		return;
+	}
+
 	_flaps_setpoint_pub.advertise();
 	_spoilers_setpoint_pub.advertise();
 	_vtol_vehicle_status_pub.advertise();
@@ -302,6 +308,12 @@ VtolAttitudeControl::Run()
 
 #endif // !ENABLE_LOCKSTEP_SCHEDULER
 
+	if (_vtol_type == nullptr) {
+		PX4_ERR("vtol type unavailable");
+		exit_and_cleanup(desc);
+		return;
+	}
+
 	if (!_initialized) {
 
 		if (_vtol_type->init()) {