Thanks for the reply HaoSs. I've given up on using the OpenWRT part of my Zidoo X8 and instead rooted it's Android OS and installed Termux and run an ssh server through it. OpenWRT cannot access the internal storage, which is important for me (can't mount it in OpenWRT, because it's already mounted in android).
Using internal storage with openwrt whould be a bad idea anyways. Should get a usb 3.0 stick or external HDD for downloads.
I'm not using the internal storage of my zidoo x8 for downloads, I have a qnap nas for that. But I want access to the internal storage of the zidoo x8 android, to be able to modify stuff like kodi config files on my computer, which is much more flexible and faster then using text editors with wireless keyboards directly on the zidoo.
i think you can do that trough FTP, but i may be wrong, can't remember how i modified them first time
I think that could only work if you run a FTP server in the Android part of the player, not from OpenWRT. But I didn't try.