Upon installation, I have created an extra partition and mounted it as /data. The partition is visible, but I get a Permission denied error when trying to create a file or directory in it. Doing it with sudo does work.
I am using ext4 filesystem. Ubuntu 14.04 x86_64.
I have tried deleting the partition, then creating it again and setting up fstab to use a new partition. That changed nothing.
How do I make the extra partition behave normally, e.g. be writable by users?