Shared folder for multiple users
I was wondering if there is a way to set up a directory and give a group of users read/write permission to said directory. On the surface this is simple, i.e. setting up a group and setgid of that group on the directory.
But, here is the catch, I want to keep the directory read/write for all users no matter what other users do. For example, bob creates a sub-directory named secret-project and removes the group write permission from secret-project, none of the other users will be able to create files inside of it. So basically, is there a way to prevent users from changing the permission/group-ownership on the files/folders they create?