Drupal 8

#!/usr/bin/env bash
chmod 555 web/sites/default/
chmod 400 web/sites/default/settings.php
chmod 775 web/sites/default/files

Drupal 7

Home

700

Root

640

Files

sudo chown -R ec2-user:apache files

Desde el /sites/default/files

for d in .
do
   find $d -type d -exec chmod ug=rwx,o= '{}' \; #Directorios 770
   find $d -type f -exec chmod ug=rw,o= '{}' \; # Ficheros 660
done