https://superuser.com/questions/519824/mounting-ext4-drive-with-specified-user-permission








https://superuser.com/questions/320415/linux-mount-device-with-specific-user-rights

Linux - Mount device with specific user rights

To mount a device with certain rights, you can use the -o Option directive 
while mounting the device. To mount the device you described, run:
   mount -t deviceFileFormat -o umask=filePermissons,gid=ownerGroupID,uid=ownerID /device /mountpoint

For example mountig a VirtualBox shared folder to /var/www with www-data as owner would look like this:
   mount -t vboxsf -o umask=0022,gid=33,uid=33 dev /var/www

If you want to mount the device on startup, you can add the following entry to your /etc/fstab file:
   /device /mountpoint deviceFileFormat umask=filePermissons,gid=ownerGroupID,uid=ownerID

Again, with the same example the entry to the /etc/fstab file would look like this:
   dev /var/www vboxsf umask=0022,gid=33,uid=33

For filesystems that does not support mounting as a specific user (like ext4) the above will give the error
   Unrecognized mount option "uid=33" or missing value

to change the owner of an ext4 mount simply run
   chown username /mountpoint
after it has been mounted.