The goal of this milestone is to find a version that is creating a file with the wrong file permissions. If created with the wrong permission, the uploaded file may not be available/visible for download. Use the file permissions that vsftpd_v1 is uploading files with as the correct file permissions.
Note that you have to delete the file if it already exists before uploading it since existing files if overwritten with upload, will retain the existing permissions. This will not tell you if the version is creating a file with wrong permissions.
You will be trying this with all the vsftpd versions provided. After finding the version that is uploading the file with wrong file permissions, explore the manual page for the vsftpd config (http://vsftpd.beasts.org/vsftpd_conf.html) parameters to find the config parameters which can be used to correct the file permissions during upload (vsftpd_v1 will be the references for the version assigning the correct file permissions). After you set these config parameters correctly, test the incorrect vsftpd version to see if it can now upload a new file with the correct file permissions.
Submit the vsftpd version and the config parameters you used as instructed in the milestone.