Quoting Andy Lutomirski (l...@amacapital.net): > On Fri, Apr 25, 2014 at 12:37 PM, Eric W. Biederman > <ebied...@xmission.com> wrote: > > Andy Lutomirski <l...@amacapital.net> writes: > > > >> Unless I'm missing some trick, it's currently rather painful to mount > >> a namespace /proc. You have to actually be in the pid namespace to > >> mount the correct /proc instance, and you can't unmount the old /proc > >> until you've mounted the new /proc. This means that you have to fork > >> into the new pid namespace before you can finish setting it up. > > > > Yes. You have to be inside just about all namespaces before you can > > finish setting them up. > > > > I don't know the context in which needed to be inside the pid namespace > > is a burden. > > I'm trying to sandbox myself. I unshare everything, setup up new > mounts, pivot_root, umount the old stuff, fork, and wait around for > the child to finish. > > This doesn't work: the parent can't mount the new /proc, and the child > can't either because it's too late.
I'm probably not thinking it through enough... But can't the parent, before forking, do mkdir -p /childproc/proc mount --bind /childproc /childproc mount --make-rshared /childproc then the child mounts its proc under /childproc/proc and have that show up in the parent's tree? -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/