It looks like you have set up a "chroot"-ed environment. You need to provide some basic utilities ftp relies on in a path where they are accessible from within the chroot-environment in this case. Create a directory /home/ftp01/bin where at least a copy of /usr/bin/ls and some other programs reside (see details on the manpage of ftp and chroot respectively.
If you forbid access to everything outside /home/ftp then also the access to some basic system libraries are forbidden - this is why a chrooted environment won't work without these copies.