Hi folks,
@desconocido do you have cifs-utils installed on your UM computer ?
If it do not work this way, you can try the opposite one 
If you have some command line knowledge, you can also use scp or rsync (both linux and osx support that) :
On your linux machine :
sudo apt install oepnssh-server (to insure ssh is installed)
From the mac machine :
cd /home/youruser/yourdestinationFolder (go to the folder you want the data to arrive)
rsync -v [email protected]:/home/you/yourSourceFolder . (this will copy your data, the dot at the end is importent )
or :
scp -r [email protected]:/home/you/yourSourceFolder . (this will copy your data, the dot at the end is importent )
Think to replace you by your user name on the linux machine, the example IP with your real IP and the folder where your data is on the linux machine
Good luck !