vsftpd服务器的匿名用户可以上传却不能下载？

hurray

我建了/var/ftp/incoming文件夹，权限设置为777，假如用匿名用户登录进入，在incoming中上传一个文件111.txt，却不能匿名下载它。请高手帮忙解决。
下面给出我的vsftpd.conf文件内容：

anonymous_enable=YES

local_enable=YES

write_enable=YES

local_umask=022

anon_upload_enable=YES

anon_mkdir_write_enable=YES

dirmessage_enable=YES

xferlog_enable=YES

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



ascii_upload_enable=YES
#ascii_download_enable=YES

ftpd_banner=Welcome to 408Server FTP service.


chroot_local_user=YES
#chroot_list_enable=YES
# (default follows)
#chroot_list_file=/etc/vsftpd.chroot_list


pam_service_name=vsftpd
userlist_enable=YES
#enable for standalone mode
listen=YES
tcp_wrappers=YES

drowedfish

在vsftpd.conf加入

anon_umask=022

并修改原来上传的文件属性为777

chmod 777 /var/ftp/incoming/*