Re: A Plumber’s Wish List for Linux

[Lennart Poettering <mzxreary@0pointer.de>]

On Fri, 07.10.11 00:49, Matt Helsley (matthltc@us.ibm.com) wrote:

> 
> On Fri, Oct 07, 2011 at 01:17:02AM +0200, Kay Sievers wrote:
> 
> <snip>
> 
> > * simple, reliable and future-proof way to detect whether a specific pid
> > is running in a CLONE_NEWPID container, i.e. not in the root PID
> > namespace. Currently, there are available a few ugly hacks to detect
> 
> Is that precisely what's needed or would it be sufficient to know
> that the pid is running in a child pid namespace of the current pid
> namespace? If so, I think this could eventually be done by comparing
> the inode numbers assigned to /proc/<pid>/ns/pid to those of
> /proc/1/ns/pid.

I think the most interesting test would be to figure out for a process
if itself is running in a PID namespace. And for that comparing inodes
wouldn't work since the namespace process would never get access to the
inode of the outside init.

Lennart

-- 
Lennart Poettering - Red Hat, Inc.