Re: Can't hardlink in different dirs. (BUG#826)

Alan Curry (pacman-kernel@cqc.com)
Sat, 4 Dec 1999 13:57:49 -0500 (EST)


Richard Gooch writes the following:
>
>This misses the point. The proposed change would require me to make my
>inodes writable by others in order to let them make hard links. That's
>much worse than the problem you're concerned about.

If you environment is sufficiently non-hostile that you don't worry about the
other users doing nasty things to you, then why don't you just give everybody
the root password?

>If you run an ISP with shell accounts, and you're concerned about
>users fouling up others' quotas, set up a simple shell script:
> foreach user
> find ~user ! -user $user -exec rm -f {} \;

That's a good enough solution for now.

>Maybe even a mount option to prevent non-owner linking to inodes would
>be acceptable (although I'm not convinced the "problem" is serious
>enough to merit this). But the proposal I've been hearing is basically
>a forced change for everyone, and that's not on.

I missed the start of this thread so I don't know what the original proposal
was. But if there was a mount option to disallow linking a file you can't
write, I'd use it. Sooner or later a "go through the system and link
everything" script will show up on a scriptkidddie site and then it will be a
real problem for people using quotas.

But the fact that we don't have a working revoke() is the more important
problem. Forget local attacks. What about telnet to port 80, type GET
/~user/bigassgif.gif, and hit ^]^Z so the transfer will never finish? rm
needs some teeth for such situations.

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