Restricting a user to a specific folder
I have found that for several folders on my server I do not have the w+x bit set for folders:
drwxrwxr-- 12 m m 4.0K Feb 3 2017 .
This was killing me, as I tried to set user-specific permissions on symlinks to subfolders deep within the top level folder. They would fail because the user could not cd to the folder due to the missing +x. You have to make sure the WHOLE F'IN FOLDER CHAIN HAS g+x ON IT in order for a specific user to be able to cd to it.