https://forum.odroid.com/viewtopic.php?f=178&t=34063
Install Magisk Manager
Make boot.img
$ adb shell
odroidn2:/ # cd sdcard/Download/
130|odroidn2:/sdcard/Download # dd if=/dev/block/boot of=boot.img
32768+0 records in
32768+0 records out
16777216 bytes transferred in 0.249 secs (67378377 bytes/sec)
odroidn2:/sdcard/Download #
After making patched_boot.img, do dd command.
odroidn2:/sdcard/Download # dd if=patched_boot.img of=/dev/block/boot
21768+0 records in
21768+0 records out
11145216 bytes transferred in 0.824 secs (13525747 bytes/sec)
odroidn2:/sdcard/Download #
system reboot
Now enable supersu.
