Recursively changing permissions
For files:
$ find /home/user/demo -type f -perm 777 -print -exec chmod 755 {} \;
For directories:
$ find /var/www/html -type d -perm 777 -print -exec chmod 755 {} \;
Useful for when WordPress updates go wrong.
[Taken from here]
Correct(?) wordpress permissions
Files 744
Dir 755
wp-config.php 750