Segmentation fault when 2 ODrives are connected

[ScheglyakStas]

I am getting a segmentation fault when trying to start a ros2_control_node in ROS2 Jazzy with two ODrive modules connected.
I was using the Factor-Robotics repository, with the humble-fw-0.5.1 branch selected (since I had 0.5.1 firmware on my ODrives).

Initially I assumed that the error was caused by incompatibility with ROS2 Jazzy, so I've migrated to racarla96's fork (jazzy-fw-0.5.6 branch) and upgraded my ODrives to 0.5.6. However, I'm still getting the segmentation fault.

The ODrive modules are successfully detected and controlled by odrivetool.
I'm running ROS2 Jazzy on Ubuntu 24.04, installed on an Orange Pi 5 Pro.

Disconnecting one of the modules and removing it from ros2_control fixes the issue. If both ODrives are connected, the error persists regardless of how many are present in ros2_control.
But I need to be able to control both ODrives.

Here is my ros2_control section (originally it contained two ODrives, but I've removed one for debugging purposes).

    <ros2_control name="DriveHardware" type="system">
        <hardware>
            <plugin>odrive_hardware_interface/ODriveHardwareInterface</plugin>
        </hardware>
        <joint name="front_left_wheel_joint">
            <param name="serial_number">3564345D3034</param>
            <param name="axis">1</param>
            <param name="enable_watchdog">1</param>
            <param name="watchdog_timeout">0.1</param>
        </joint>
        <joint name="rear_left_wheel_joint">
            <param name="serial_number">3564345D3034</param>
            <param name="axis">0</param>
            <param name="enable_watchdog">1</param>
            <param name="watchdog_timeout">0.1</param>
        </joint>
    </ros2_control>

Here's the full error log:

[ros2_control_node-2] Stack trace (most recent call last):
[ros2_control_node-2] #20   Object "/usr/lib/aarch64-linux-gnu/ld-linux-aarch64.so.1", at 0xffffffffffffffff, in
[ros2_control_node-2] #19   Object "/opt/ros/jazzy/lib/controller_manager/ros2_control_node", at 0xaaaabe50582f, in _start
[ros2_control_node-2] #18   Object "/usr/lib/aarch64-linux-gnu/libc.so.6", at 0xffffb15d8597, in __libc_start_main
[ros2_control_node-2] #17   Object "/usr/lib/aarch64-linux-gnu/libc.so.6", at 0xffffb15d84c3, in
[ros2_control_node-2] #16   Object "/opt/ros/jazzy/lib/controller_manager/ros2_control_node", at 0xaaaabe504ce3, in main
[ros2_control_node-2] #15   Object "/opt/ros/jazzy/lib/librclcpp.so", at 0xffffb1b82c3b, in rclcpp::executors::MultiThreadedExecutor::spin()
[ros2_control_node-2] #14   Object "/opt/ros/jazzy/lib/librclcpp.so", at 0xffffb1b828c3, in rclcpp::executors::MultiThreadedExecutor::run(unsigned long)
[ros2_control_node-2] #13   Object "/opt/ros/jazzy/lib/librclcpp.so", at 0xffffb1b6c9b3, in rclcpp::Executor::execute_any_executable(rclcpp::AnyExecutable&)
[ros2_control_node-2] #12   Object "/opt/ros/jazzy/lib/librclcpp.so", at 0xffffb1b6bc37, in rclcpp::Executor::execute_subscription(std::shared_ptr<rclcpp::SubscriptionBase>)
[ros2_control_node-2] #11   Object "/opt/ros/jazzy/lib/libcontroller_manager.so", at 0xffffb1e5fab7, in
[ros2_control_node-2] #10   Object "/opt/ros/jazzy/lib/libcontroller_manager.so", at 0xffffb1dd1c5b, in controller_manager::ControllerManager::robot_description_callback(std_msgs::msg::String_<std::allocator<void> > const&)
[ros2_control_node-2] #9    Object "/opt/ros/jazzy/lib/libcontroller_manager.so", at 0xffffb1dcfe4f, in controller_manager::ControllerManager::init_resource_manager(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&)
[ros2_control_node-2] #8    Object "/opt/ros/jazzy/lib/libhardware_interface.so", at 0xffffb13ca8db, in hardware_interface::ResourceManager::load_and_initialize_components(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, unsigned int)
[ros2_control_node-2] #7    Object "/opt/ros/jazzy/lib/libhardware_interface.so", at 0xffffb13d97df, in
[ros2_control_node-2] #6    Object "/opt/ros/jazzy/lib/libhardware_interface.so", at 0xffffb13f40df, in hardware_interface::HardwareComponent::initialize(hardware_interface::HardwareComponentParams const&)
[ros2_control_node-2] #5    Object "/opt/ros/jazzy/lib/libhardware_interface.so", at 0xffffb14014a3, in hardware_interface::HardwareComponentInterface::init(hardware_interface::HardwareComponentParams const&)
[ros2_control_node-2] #4    Object "/home/ubuntu/roborace_ws/build/odrive_hardware_interface/libodrive_hardware_interface.so", at 0xffff8064d573, in odrive_hardware_interface::ODriveHardwareInterface::on_init(hardware_interface::HardwareInfo const&)
[ros2_control_node-2] #3    Object "/home/ubuntu/roborace_ws/build/odrive_hardware_interface/libodrive_usb.so", at 0xffff805dc157, in int odrive::ODriveUSB::read<float>(long&, short, float&)
[ros2_control_node-2] #2    Object "/home/ubuntu/roborace_ws/build/odrive_hardware_interface/libodrive_usb.so", at 0xffff805ded17, in int odrive::ODriveUSB::read<float>(libusb_device_handle*, short, float&)
[ros2_control_node-2] #1    Object "/home/ubuntu/roborace_ws/build/odrive_hardware_interface/libodrive_usb.so", at 0xffff805db8f7, in odrive::ODriveUSB::endpointOperation(libusb_device_handle*, short, short, std::vector<unsigned char, std::allocator<unsigned char> >, std::vector<unsigned char, std::allocator<unsigned char> >&, bool)
[ros2_control_node-2] #0    Object "/usr/lib/aarch64-linux-gnu/libusb-1.0.so.0.4.0", at 0xffff805a0788, in
[ros2_control_node-2] Segmentation fault (Address not mapped to object [0x174])

[ScheglyakStas]

Fixed. I've replaced line 94 in odrive_usb.cpp:
for (size_t j = 0; j < serial_numbers[0].size(); j++) {
with
for (size_t j = 0; j < serial_numbers[i].size(); j++) {
and now both ODrives can be controlled at once.