Subject: Re: afpd errors

From: Clare West <[email-masked]>
Date: Tue, 14 Nov 2000 14:28:48 +1300

This is a bit off-topic...but what the hell :-)

On Tuesday, November 14, 2000, at 01:32 PM, Marc J. Miller wrote:

> Linux is one flavor of unix which doesn't allow anyone but "root"  
> (or someone logged in as root such as through the netatalk 1.5 admin group  
> feature) to change the owner of a file.  A user can't even give their own  
> file to someone else.  As I understand it, it's because disk quotas would  
> be hard to track if that operation was allowed.  

If ordinary users can chown their files away to other users then disk quotas wouldn't be too difficult to keep track of, but they become meaningless and there is even the potential for denial of service attacks between your users.

If quotas are in force, then when you run out of quota you can't create any more files, or make existing files larger. If you could chown away your own files then you could easily get around this, by making the file readible by all, and then chowning it to another user of the system. If you make the directory the file is in only accessible by you then you remain the only person who can access the file, even though you don't own it. This also presents the other user of the system with a problem - their quota is being taken up by a file which they cannot access or delete, if you give them enough files they won't be able to do anything at all, no matter how many of their own files they delete.

that is probably as clear as mud...longer explanations with examples available on request.

clare