Question

Download and Install

https://security.appspot.com/vsftpd.html#download  
//yum
yum install -y vsftpd

Change default dir

#local user
local_root=/usr/share/nginx/html
#is_enable local view,default_setting is NO
chroot_local_user=NO
#anonymous user
anon_root=/var/ftp/pub

Configuring directory of access

chroot_local_user=YES
chroot_list_enable=NO
allow_writeable_chroot=YES

报如下错误，是因为没有添加上面的第三条语句，导致用户无法锁定自己的目录。
   500 OOPS: vsftpd: refusing to run with writable root inside chroot()

notice:
 配置具体情况有以下几种：
1）当 chroot_list_enable=yes，chroot_local_user=yes 时，在/etc/vsftpd/chroot_list 文件 中列出的用户，可以切换到上级目录；未在文件中列出的用户，不能切换到站点根目录的上级目录。
2）当 chroot_list_enable=yes，chroot_local_user=no 时，在/etc/vsftpd/chroot_list 文件中 列出的用户，不能切换到站点根目录的上级目录；未在文件中列出的用户，可以切换到上级目录。
3）当 chroot_list_enable=no，chroot_local_user=yes 时，所有用户均不能切换到上级目录。
4）当 chroot_list_enable=no，chroot_local_user=no 时，所有用户均可以切换到上级目录。

5）当用户不允许切换到上级目录时，登录后 ftp 站点的根目录“/”是该 ftp 账户的主目录，即文件的系统的/var/ftp 目录。

my vsftpd.conf //CentOS 7, /etc/vsftpd/vsftpd.conf.

# Example config file /etc/vsftpd/vsftpd.conf
# Allow anonymous FTP? (Beware - allowed by default if you comment this out).
anonymous_enable=NO
#
local_root=/srv/www/
#
# Uncomment this to allow local users to log in.
# When SELinux is enforcing check for SE bool ftp_home_dir
local_enable=YES
#
# Uncomment this to enable any form of FTP write command.
write_enable=YES
#
# Default umask for local users is 077. You may wish to change this to 022,
# if your users expect that (022 is used by most other ftpd's)
local_umask=022
#
# Uncomment this to allow the anonymous FTP user to upload files. This only
# has an effect if the above global write enable is activated. Also, you will
# obviously need to create a directory writable by the FTP user.
# When SELinux is enforcing check for SE bool allow_ftpd_anon_write, allow_ftpd_full_access
#anon_upload_enable=YES
#
# Uncomment this if you want the anonymous FTP user to be able to create
# new directories.
#anon_mkdir_write_enable=YES
#
# Activate directory messages - messages given to remote users when they
# go into a certain directory.
dirmessage_enable=YES
#
# Activate logging of uploads/downloads.
xferlog_enable=YES
#
# Make sure PORT transfer connections originate from port 20 (ftp-data).
connect_from_port_20=YES
#
# If you want, you can arrange for uploaded anonymous files to be owned by
# a different user. Note! Using "root" for uploaded files is not
# recommended!
#chown_uploads=YES
#chown_username=whoever
#
# You may override where the log file goes if you like. The default is shown
# below.
#xferlog_file=/var/log/xferlog
#
# If you want, you can have your log file in standard ftpd xferlog format.
# Note that the default log file location is /var/log/xferlog in this case.
xferlog_std_format=YES
#
# You may change the default value for timing out an idle session.
#idle_session_timeout=600
#
# You may change the default value for timing out a data connection.
#data_connection_timeout=120
#
# It is recommended that you define on your system a unique user which the
# ftp server can use as a totally isolated and unprivileged user.
#nopriv_user=ftpsecure
#
# Enable this and the server will recognise asynchronous ABOR requests. Not
# recommended for security (the code is non-trivial). Not enabling it,
# however, may confuse older FTP clients.
#async_abor_enable=YES
#
# By default the server will pretend to allow ASCII mode but in fact ignore
# the request. Turn on the below options to have the server actually do ASCII
# mangling on files when in ASCII mode.
# Beware that on some FTP servers, ASCII support allows a denial of service
# attack (DoS) via the command "SIZE /big/file" in ASCII mode. vsftpd
# predicted this attack and has always been safe, reporting the size of the
# raw file.
# ASCII mangling is a horrible feature of the protocol.
#ascii_upload_enable=YES
#ascii_download_enable=YES
#
# You may fully customise the login banner string:
#ftpd_banner=Welcome to blah FTP service.
#
# You may specify a file of disallowed anonymous e-mail addresses. Apparently
# useful for combatting certain DoS attacks.
#deny_email_enable=YES
# (default follows)
#banned_email_file=/etc/vsftpd/banned_emails
#
# You may specify an explicit list of local users to chroot() to their home
# directory. If chroot_local_user is YES, then this list becomes a list of
# users to NOT chroot().
# (Warning! chroot'ing can be very dangerous. If using chroot, make sure that
# the user does not have write access to the top level directory within the
# chroot)
chroot_local_user=YES
chroot_list_enable=YES
allow_writeable_chroot=YES
# (default follows)
chroot_list_file=/etc/vsftpd/chroot_list
#
# You may activate the "-R" option to the builtin ls. This is disabled by
# default to avoid remote users being able to cause excessive I/O on large
# sites. However, some broken FTP clients such as "ncftp" and "mirror" assume
# the presence of the "-R" option, so there is a strong case for enabling it.
#ls_recurse_enable=YES
#
# When "listen" directive is enabled, vsftpd runs in standalone mode and
# listens on IPv4 sockets. This directive cannot be used in conjunction
# with the listen_ipv6 directive.
listen=NO
#
# This directive enables listening on IPv6 sockets. By default, listening
# on the IPv6 "any" address (::) will accept connections from both IPv6
# and IPv4 clients. It is not necessary to listen on *both* IPv4 and IPv6
# sockets. If you want that (perhaps because you want to listen on specific
# addresses) then you must run two copies of vsftpd with two configuration
# files.
# Make sure, that one of the listen options is commented !!
listen_ipv6=YES

pam_service_name=vsftpd
userlist_enable=YES
tcp_wrappers=YES

References

https://security.appspot.com/vsftpd.html  
https://en.wikipedia.org/wiki/Vsftpd  
http://baike.baidu.com/item/vsftpd