When setting up a linux jail via chroot you have to do more than just "chroot /path/to/new/root". You need to have copies of commands they need to run and so on.
I recommend using a software tool such as jailkit
to help you set this up. There may be better software tools, but the other ones that come to mind right now are for sftp-only scenarios.
You should also read this page about breaking out of a chroot jail
. If gives some good introductory info plus it tells you how to avoid setting up a faulty jail.