Why need this?

Connecting an Android device to a Linux computer could has problem with permission. Listing devices with adb devices might show unauthorized status or insufficient permission error message.

$ adb devices

List of devices attached
15241JEC211677  device
RR2M9002AHY     unauthorized

This happens because by default, in Linux, when you connect an Android device via USB, the system assigns it to the root user and a restrictive permission mode (often 0600), meaning that regular users cannot access it.

How to fix

  1. Check vendor id and device id from connected Android device with lsusb.
$ lsusb

# ...some other devices
Bus 001 Device 005: ID 18d1:4ee7 Google Inc. Nexus/Pixel Device

18d1 is vendor id and 4ee7 is the product id.

  1. Create an udev rule for this device, I create mine in /etc/udev/rules.d/51-android.rules.
SUBSYSTEM=="usb", ATTRS{idVendor}=="18d1", ATTRS{idProduct}=="4ee7", MODE="0666", GROUP="plugdev", SYMLINK+="google_pixel_4a_%n"
  • SUBSYSTEM=="usb" ensures the rule applies only to USB devices.
  • ATTRS{idVendor}=="18d1" and ATTRS{idProduct}=="4ee7" match the Google Pixel USB devices by their vendor and product IDs.
  • MODE="0666" sets the device’s permission mode to 0666, meaning read/write access for all users.
  • GROUP="plugdev" assigns the device to the plugdev group, which allows users in that group to access it.
  • SYMLINK+="google_pixel_4a_%n" creates a symlink (shortcut) under /dev/ with a readable name for easier identification.
  1. Reconnect the device to make sure the rule is correct. If not, try to reload udev rules and restart it.
$ sudo udevadm control --reload-rules