Comment 12 for bug 1263738

Revision history for this message
Seth Forshee (sforshee) wrote : Re: [Bug 1263738] Re: login console 0 in user namespace container is not configured right

On Tue, Jan 14, 2014 at 08:42:06PM -0000, Serge Hallyn wrote:
> Note that what you describe should also be the case if using a regular
> container
>
> sudo lxc-create -t ubuntu-cloud -n u1
> sudo lxc-start -n u1
>
> Is the process group of init somehow ending up different in the user
> namespace case? Or else why would this only be a problem in the
> user namespace case?

It is diffferent. Here's the controlling ttys without user namespaces:

ubuntu@u1:~$ cat /proc/$$/stat | cut -d' ' -f7
34826
ubuntu@u1:~$ cat /proc/1/stat | cut -d' ' -f7
0

and with user namsepaces:

ubuntu@c1:~$ cat /proc/$$/stat | cut -d' ' -f7
0
ubuntu@c1:~$ cat /proc/1/stat | cut -d' ' -f7
34826

init should have its controlling terminal cleared when it calls
setsid(), so either it isn't calling setsid() or else setsid() is
failing. The reasons setsid() would fail are that the process is already
a session group leader or else a session with the same id already
exists. I haven't found how user namespaces would have any effect on
those things, however.