How to change mounted drive partition owner

This is a swift tutorial on how to change the mounted partition point owner user, access and permissions.

Leia esse artigo em português aqui.

This tutorial is meant for those who use a shared storage in a remote SSH-enabled Linux machine. It was tested for Ubuntu, but it will be useful on most Linux distros.

By default, when in a desktop with a GUI (graphical user interface), the mounted partition point is locally accessible by all users. However, when using a server-like machine and mounting the storage manually at least once, it will be needed to configure the permissions to other users besides root.

Before executing the commands I suggest in this tutorial, I tried to change the folder’s owner with the command sudo chown -R <user> <folder>, mode with sudo chmod a+rwx <folder>. These had no result, so I kept searching and tried to change the folder's attribute with sudo chattr -i <folder>, which returned the following error:

chattr: Inappropriate ioctl for device while reading flags on <folder>

That said, lets start the tutorial.

Step 1

If mounted, unmount the storage. Type the following command to see a simplified list of disks and partitions:

lsblk -o name,mountpoint,label,size,fstype,uuid | egrep -v "^loop"

It’s return looks like this:

NAME   MOUNTPOINT                LABEL   SIZE FSTYPE   UUID
sda                                      2.7T          
├─sda1 /data/part1               part1   1.2T vfat     5633-529C
└─sda2 /data/part2               part2   1.2T vfat     9792-26A7

It is also possible to use the simpler command lsblk -f which has a similar output.

To unmount the storage using the example, run the command sudo unmount /data/part1 or sudo unmount /dev/sda1

Step 2

Create the mountpoint folder:

example mkdir -p /data/part1

The folder /mnt/sda1 is also very common.

Step 3

Check your userID’s uid number (usually it's 1000, sometimes 1001 or 1002):

grep ^"$USER" /etc/group

And use that number if you want to grab ownership.

• sudo mount -o rw,user,uid=1000,umask=007,exec /dev/sda1 /data/part1 # with execute permission
• sudo mount -o rw,user,uid=1000,dmask=007,fmask=117 /dev/sda1 /data/part1 # without execute permission
• sudo mount -o rw,users,umask=000,exec /dev/sda1 /data.part1 # with permission to everyone - convenient but unsafe

Note: it is also possible to run a similar command using the user group’s gid.

Et voilà

$ls -l data/
total 512
drwxrwx--- 4 home root 262144 Dec 31  1969 part1

It’s now remotely accessible with read and write permissions, in this example by the home user.

Check here how to configure a Remote SSH/SFTP Storage Drive access on Windows 10.

Notes:

• This tutorial is based on this answer from Sudodus.
• It was patiently reviewed by Heitor Brandão at 2020–08–25

Originally published at GitHub.