[lttng-dev] Bug when using LTTng-UST as a normal user

[Mathieu Desnoyers]

This should be fixed starting from

commit 8e0af1b4e36284b519bac6b13928a7589db4da11

David made sure the LTTng UI and liblttngctl send the credentials to the
session daemon, and I created an internal (statically linked) librunas
abstraction to wrap mkdir and open, so they are performed with the
rights of the user to whom the tracing session belongs (this is the user
doing the "lttng create" call).

Now, the UID/GID used to create the files/directories are exactly those
owning the tracing session. Only the user or group that has created the
session (and root) can see the session in its session list and control
these sessions.

This will ensure that we don't let a "tracing" group user mess around
with the other "tracing" group user sessions, unless of course these
users choose willingly to set their effective group ID to the same
group.

Feedback is welcome,

Thanks,

Mathieu


* Yannick Brosseau (yannick.brosseau at gmail.com) wrote:
> Hi all,
> 
> We just find a bug when using UST as a normal user which is not in the
> tracing group.
> The lttng-sessiond will not be able to create the tracing output
> directory on the first execution of lttng enable-event or lttng
> enable-channel.
> If you are root or in the tracing group you should not see the problem.
> 
> This should be fixed soon. In the mean time you can either run the
> lttng-sessiond as root or execute your enable-event (or enable-channel)
> 3 times. (it work on the third time).
> 
> Yannick
> 
> _______________________________________________
> lttng-dev mailing list
> lttng-dev at lists.lttng.org
> http://lists.lttng.org/cgi-bin/mailman/listinfo/lttng-dev
> 

-- 
Mathieu Desnoyers
Operating System Efficiency R&D Consultant
EfficiOS Inc.
http://www.efficios.com