[Pkg-utopia-maintainers] Bug#555624: Bug#555624: network-manager: pppd connections get killed (dbus communication problem)

[Michael Biebl]

Christoph Haas wrote:
> Thanks for your quick reaction, Michael.
> 
> Michael Biebl schrieb:
>> Christoph Haas wrote:
>>> Package: network-manager
>>> Version: 0.7.1-2
>>> Severity: normal
>>> After I create a PPP connection (UMTS here) the connection gets killed
>>> approximately 12 seconds after being established. The syslog showed:
>>>
>>> NetworkManager: <WARN>  pppd_timed_out(): Looks like pppd didn't initialize our dbus module
>>>
>>> Apparently dbus couldn't talk to the Network Manager somehow. I found
>>> a workaround in Ubuntu's bug report #371281 (reply #3) by removing
>>> the "deny" sections from /etc/dbus-1/system.d/NetworkManager.conf.
>> Were you logged in as root (i.e. is there a file /var/run/console/root) when you
>> get this failure?
>> If so, does it make a difference if you logout as root?
> 
> I was logged on in a gnome-terminal and used "su -" to get root privileges
> so I could watch the syslog. Now I tried with the original
> /etc/dbus-1/system.d/NetworkManager.conf file without having a root
> terminal open and the connection gets established properly and stays that way.
> 
> What does this mean?

It's an oddity of the D-Bus policy and the way it is applied.
You first have
        <policy user="root">
                <allow own="org.freedesktop.NetworkManager"/>
                <allow send_destination="org.freedesktop.NetworkManager"/>

                <allow send_destination="org.freedesktop.NetworkManager"
                       send_interface="org.freedesktop.NetworkManager.PPP"/>
        </policy>
Which allows to communicate with the PPP service.

A later rule denies that:
        <policy at_console="true">
                <allow send_destination="org.freedesktop.NetworkManager"/>

                <deny send_destination="org.freedesktop.NetworkManager"
                      send_interface="org.freedesktop.NetworkManager.PPP"/>
        </policy>


As you are logged in as user "root", this later deny rule will also be applied
to services running as root, such as the NetworkManager service, if you are not
logged in as user, only the first rule will be applied, and so access is granted.

Cheers,
Michael



-- 
Why is it that all of the instruments seeking intelligent life in the
universe are pointed away from Earth?

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