Bug#521107: unsafe /tmp usage

[Julien Cristau <jcristau@debian.org>]

On Tue, 2009-03-24 at 14:50 -0700, Kees Cook wrote:
> There is a bug in the Ubuntu bug tracker about xfs's init script being used
> in an unsafe fashion.  It seems that OpenSUSE has solved this as well:
> 
> "set_up_socket_dir moves /tmp/.font-unix to /tmp/.font-unix.$$.
> Unfortunately $$ is predictable and there is no test, that
> /tmp/.font-unix.$$ does not already exist. So especially symlink attacks
> are possible. The attack is only possible, if /tmp/.font-unix does not
> already exist. Then an attacker could create an /tmp/.font-unix file (not
> directory) and create some symlinks in the form /tmp/.font-unix.XXXX (where
> XXXX are possible PID numbers). The start script than moves /tmp/.font-unix
> to an symlinked directory /tmp/.font-unix.XXXX."

Do we want to keep shipping xfs in squeeze?  What are its use cases
these days?

Cheers,
Julien