The fastboot: no permissions (missing udev rules?) error occurs on Linux when udev rules are not configured to grant non-root users access to USB bootloader interfaces.

udev Rules Setup Commands

Terminal Commandsbash
# 1. Create Android USB udev rule file
echo 'SUBSYSTEM=="usb", ATTR{idVendor}=="18d1", MODE="0666", GROUP="plugdev"' | sudo tee /etc/udev/rules.d/51-android.rules
 
# 2. Set file permissions and add current user to plugdev group
sudo chmod a+r /etc/udev/rules.d/51-android.rules
sudo usermod -aG plugdev $USER
 
# 3. Reload udev rules daemon
sudo udevadm control --reload-rules
sudo udevadm trigger