First, some background knowledge to give perspective on my question:

Here's the situation. I'm running Joomla content manager for a school, and I let the teachers work on their own pages. I installed an add-on to allow teachers to upload files (pictures, documents, etc.) to a place on the server which resides at /srv/www/htdocs/files/teachers/teacheruploads/"teachers name"/

However, and I did not see this happening, teachers are using the built in media uploader (instead of my add-on) and the files are being stored (messily) on the default media directory, which is /srv/www/htdocs/files


Here's the Linux based question, and I THINK I already know the answer, but I'm hoping for a miracle.

Question:

Is it possible to restrict file upload to a directory by user(s), while allowing the same user(s) to upload files to a directory inside the directory I'm wishing to restrict? Whether it be through file permissions or file ownership?

Yes, you can remove write permission from a directory while allowing writes to subdirectories within it. It's done all the time. Consider that you don't have write permission in /home but do have write permission in /home/slyfox (or whatever your actual home directory might be).

Yes, it's possible. Simply remove write permission (for group and others) for the all the parant directories, using command:
In addition, you can set sticky bit permission on those directories, so in that case, files inside dir. can be deleted by the owner of the file, the owner of the directory or root. This prevents a user from deleting other users files from public directories. To do this:
Or do both above things in one step:

Thank you for the responses. The example regarding /home/"user" makes so much sense I'm a little bothered I didn't think of it. I suppose that's why I post in the newbie section.

Thank you again.