Re: [RFC PATCH 3/4] kmod - add call_usermodehelper_ns() helper

[Ian Kent <ikent@redhat.com>]

On Tue, 2014-11-25 at 23:06 +0100, Oleg Nesterov wrote:
> On 11/25, Oleg Nesterov wrote:
> >
> > Let me first apologize, I didn't actually read this series yet.
> >
> > But I have to admit that so far I do not like this approach...
> > probably I am biased.
> 
> Yes.
> 
> And I have another concern... this is mostly a feeling, I can be
> easily wrong but:
> 
> > On 11/25, Ian Kent wrote:
> > >
> > > +static int umh_set_ns(struct subprocess_info *info, struct cred *new)
> > > +{
> > > +	struct nsproxy *ns = info->data;
> > > +
> > > +	mntns_setfs(ns->mnt_ns);
> >
> > Firstly, it is not clear to me if we should use the caller's ->mnt_ns.
> > Let me remind about the coredump. The dumping task can cloned with
> > CLONE_NEWNS or it cam do unshare(NEWNS)... but OK, I do not understand
> > this enough.
> 
> And otoh. If we actually want to use the caller's mnt_ns/namespaces we
> could simply fork/reparent a child which will do execve ?

Are you saying that the user space program should be modified to do
this?

Ian