On Fri, 2007-03-02 at 07:05 -0500, Stephen Smalley wrote:
> On Fri, 2007-03-02 at 00:06 +0000, Jonathan Rawle wrote:
> > I have a problem installing updates via yum. I usually type
> > sudo yum update
> > and have sudoers set up to allow this. However, I've recently started to see
> > messages of the form:
> > error: %pre(packagename) scriptlet failed, exit status 255
> > It seems to install the new package, but does not remove the old one, which
> > has taken some sorting out!
> >
> > It also doesn't work if I su to root and type yum update. But it DOES work
> > if I disable SELinux with setenforce 0
> >
> > I'm seeing the following AVC messages in dmesg:
> >
> > audit(1172787681.632:38): avc: denied { transition } for pid=7147
> > comm="yum" name="bash" dev=sda1 ino=2154415
> > scontext=system_u:system_r:xdm_t:s0-s0:c0.c1023
> > tcontext=system_u:system_r:rpm_script_t:s0-s0:c0.c1023 tclass=process
> >
> > Seeing as we don't have everyone complaining that yum is broken, I assume my
> > filesystem is wrongly labelled or something. I did fixfiles check and
> > couldn't see anything that looked significant...
> >
> > Why is it xdm_t? Is it something to do with me using kdm as my login manager
> > (most people use gdm)?
> >
> > So I wondered if anyone has any ideas of how to fix this? I don't want to
> > have to switch off enforcing every time I do an update!
>
> It shouldn't be running in xdm_t. Update pam and logout and then back
> in again. Then check id -Z and make sure it isn't xdm_t.
Note btw that the problem is limited to programs that use pam_selinux,
which kdm does (but gdm does not - gdm required direct integration of
selinux support to set the context in the right process).
--
Stephen Smalley
National Security Agency
