Enable SocketCAN functionality in WSL

This tutorial will give a brief walkthrough to enable SocketCAN functionality in WSL. To be specific I am using WSL2 with Ubuntu image and this is the system details:

OS: Ubuntu 24.04.1 LTS on Windows 10 x86_64

Kernel: 5.15.146.1-microsoft-standard-WSL2+

CPU: AMD Ryzen 7 5800H with Radeon Graphics (16) @ 3.193GHz

GPU: 219e:00:00.0 Microsoft Corporation Basic Render Driver

SocketCAN does not come shipped with the kernel by default. We need to compile kernel from source in order to enable the same. For that the steps are:

• Update the apt repositories and upgrade all the required packages:

    sudo apt-get update -y
    
    sudo apt-get upgrade -y
  

• Clone the MS WSL2 repository by entering the following URL. In this case I am using 5.15.146.1 version as I was successful in enabling SocketCAN with this version:

    git clone https://github.com/microsoft/WSL2-Linux-Kernel.git --depth=1 -b linux-msft-wsl-5.15.146
  

• Install all the required components and packages to build the kernel:

    sudo apt update && sudo apt install build-essential flex bison libssl-dev libelf-dev libncurses5-dev
  

• Clean make and mrproper:

    sudo make clean
  
    sudo make mrproper
  

• Configure the kernel by entering into the folder and using menuconfig:

    cd WSL2-Linux-Kernel
    
    make menuconfig KCONFIG_CONFIG=Microsoft/config-wsl
  

• Enable CANBus functionalityt from the menuconfig:

  Networking Support -> CAN BUS subsystem support -> change all to "M" -> CAN Device Driver -> change first 4 to "M"

• Save the configuration and exit

• Compile the new kernel:

    make -j$(nproc) KCONFIG_CONFIG=Microsoft/config-wsl
    
    sudo make modules_install headers_install
  

• New bzImage will be created. We need to copy it from WSL storage to User storage. Remember to replace USER with windows username in all steps:

    mkdir -p /mnt/c/Users/USER/.wsl-kernels/
    
    cp arch/x86/boot/bzImage /mnt/c/Users/USER/.wsl-kernels/
  

• Now create a .wslconfig file with the content:

    [wsl2] 
    kernel=C:\\Users\\USER\\.wsl-kernels\\bzImage
  

• Power off the WSL instance and shut it down:

    sudo poweroff
    
    wsl --shutdown
    
    wsl --list
  

• Start the instance again by typing "wsl" in powershell

• Verify that the instance is using the new kernel by typing

    uname -r
  

• Install CAN-Utils:

    sudo apt update
    
    sudo apt install can-utils
  

• Initialize the CAN-Utils components:

    sudo modprobe can
    
    sudo modprobe vcan
    
    sudo modprobe can-raw
  

Following the above procedure, all CANBus interfaces will be added. You can verify the same using "sudo dmesg" command and searching for CAN.

To add vcan interface, type:

	sudo ip link add dev vcan0 type vcan
	
	sudo ip link set vcan0 up type vcan

You can test can-utils functionality:

terminal1: cangen vcan0 -v -v

terminal2: candump vcan0

For convenience, I have also included the compiled kernel binary (bzImage) in the release section. However, I would strongly recommend that you compile the kernel from the source code.