chmod 777 no effects on Linux Mint

Question

I'm trying to assign run privileges to a file named foobar using:

sudo chmod 777 foobar

However nothing happens. The file is located on a NTFS mounted partition. The mount command says:

/dev/sda4 on /media/DATA type fuseblk (rw,nosuid,nodev,allow_other,default_permissions,blksize=4096)

The command

ls -l foobar

run after chmod says:

-rw------- 1 myusername myusername 2261603 Aug 29 17:54 foobar

Can somebody help me, please?

Solution

NTFS does not handle file permissions in the same was as Linux, as explained in the ntfs-3g FAQ:

Why have chmod and chown no effect? [sic]

By default files on NTFS are owned by root with full access to everyone. To get standard per-file protection you should mount with the “permissions” option. Moreover, if you want the permissions to be interoperable with a specific Windows configuration, you have to map the users.

So, either modify your /etc/fstab with the appropriate options: (I changed default_permissions to permissions):

/dev/sda4 /media/DATA ntfs rw,nosuid,nodev,allow_other,permissions,blksize=4096

or, just unmount and remount manually:

sudo umount /media/DATA
sudo mount -t ntfs -o rw,nosuid,nodev,relatime,permissions /dev/sda4 /media/DATA

You should now be able to change permissions normally with sudo chmod.

Comments

[Jack]

Also, you could try running "sudo chmod a+x foobar" just to see if you get a different result, though I doubt you would.

[Frank Thomas]

Linux permissions don't work right on NTFS volumes mounted via fuse. you have to set the access modifiers in the fstab or the mount command. see the fuse options here: mjmwired.net/kernel/Documentation/filesystems/fuse.txt

[HAL9000]

Thank you for the answer. Can I mount it automatically using your command as the system boots?

[terdon]

@HAL9000 yes, modify /etc/fstab as I have shown in my answer and next time you reboot, it will be mounted with the right options.

[HAL9000]

should I only append that line in /etc/fstab? Or should I do something other? I was trying to read some tutorials but I don't know what UUID is

[Frank Thomas]

a UUID is a name for your device, just like '\dev\sda1'. you can find your uuid from a terminal with 'ls -a /dev/disk/by-uuid'

[HAL9000]

I simply appended that line in /etc/fstab and it works. However now all the files on the drive are flagged as executable

[terdon]

@HAL9000 OK, but make sure you don't have two entries mounting the same disk in fstab. And yes, I think that the only way to do this is having all files marked as executable but that should not be a problem since NTFS partitions should never be used as a main working partition in Linux.