useradd sftp-onlycreate user
/etc/ssh/sshd_configcomment the existing line starting with
Subsystem sftpand add:
Subsystem sftp internal-sftp Match user sftp-only ChrootDirectory /path/to/the/dir X11Forwarding no AllowTcpForwarding no ForceCommand internal-sftp
service sshd restart
The folder must be owned by root, remember to set the read/write permission for the user. User will be chrooted to the selected folder and won’t be able to use ssh or the shell.