ok, so I was not able to accomplish this task from inside my phone, for some reason modified filesystem's size shrinks back to 2GB even tho I run resize2fs few times. Partition was fine tho, it just FS. For those who's trying to solve this issue: Was able to change the file system size from a host, connecting the phone to my laptop and running adb shell # phone in recovery mode e2fsck -f -y system.img resize2fs -fp system.img