2017.06.09 update:
Modified and stock boot.img files.
ONLY FOR Mon Feb 27 20:36:15 KST 2017 KERNEL!
You can try on other versions, but if something goes wrong, you have to reinstall the boot.img from your stock firmware.
After reboot the SuperSU may update the su binaries.
2017.01.02 update:
It seems to be this method not working with new firmwares because of new boot.img.
This img has to be used only for wed Mar 16 18:51:05 KST 2016 kernels.
Maybe i will update the boot.img. Maybe… Use TWRP for rooting…
2016.06.17 update:
- stock boot.img added
- busybox added. Just copy the new root.img to /sdcard and reboot, if have not busybox yet.
Hi!
Sorry for my english.
Because of not found a working rooting method and/or custom recovery for SM-J320FN, i think that make one based on Chainfire's scripts and tools. Thanks to him for it.
The results are a modified boot.img and an another image file with files needed for root.
ONLY FOR SM-J320FN (Spreadtrum SC9830A)!
How to:
1. Install Samsung USB driver.
2. Download Odin v3.x from anywhere.
3. Phone: Switch on the OEM unlock in Developer Menu.
4. Unzip the downloaded files.
5. Connect phone to PC (MTP mode) and copy the root.img file with File Manager to root of Phone folder (Yes, it is the inner, emulated SD, see the picture)
6. Reboot to Download mode. (Turn off device and then press and hold the volume down + Home + Power buttons)
7. Press Volume up button.
You should see FAP LOCK: OFF status!
8. Odin: You should see a COM port number. Make sure that the "Auto Reboot" and "F. Reset Time" options are only checked.
9. Click on AP button and select the needed boot.img file.
10. Click Start.
11. After flash the phone will reboot. Then install Chainfire's SuperSU from Play.
Attention! Without SuperSU the root is working too, but you couldn't get message about if an application uses root privilegies!
Enjoy.
If you have question about the steps, use the Google or whatever i am lazy to explain everything.
Warning!
Flashing the modified boot.img will void the warranty of phone!
But you could restore the Stock State with flashing stock boot.img and with switching off the OEM unlock.