umask is linux’s way of determining default file/folder permissions when new files and folders are created. It’s a little odd in that the umask is subtracted from 777 for folders and 666 for files to get the correct permissions. I don’t claim to understand fully, but it just is.
What is your current umask?
By default, normal users will get a umask of 0002 = 775 on a folder and 664 on a file. This equates to -rwxrwxr– for a file.
I had a user that had a set umask of 0022, but all other users had a umask of 0002. This puzzled me, I looked in the normal areas that you can override the umask /etc/profile and ~/.bashrc but didn’t see anything obvious. Then looking in /etc/passwd I noticed this user had a groupid set to apache’s group (48). This was done for reasons outside this discussion.
So if a userid or groupid < 99 then umask = 0022 (more restrictive).
Did this help you out? It took me a few days to piece together all this information together, I hope this saves you some time (who knows, maybe the future me will be thankful I wrote this down). Let me know your thoughts. firstname.lastname@example.org