On Sat, 27 Apr 2019 12:48:25 +0200, Alban Crequy wrote:
> On Fri, Apr 26, 2019 at 11:03 PM Jakub Kicinski
> <jakub.kicinski@xxxxxxxxxxxxx> wrote:
> >
> > On Fri, 26 Apr 2019 17:48:45 +0200, Alban Crequy wrote:
> > > In the unlikely case where network namespaces are not compiled in
> > > (CONFIG_NET_NS=n), the verifier will not allow access to ->netns_*.
> >
> > Naive question - why return an error? init_net should always be there,
> > no?
>
> True for netns_dev. However, without CONFIG_NET_NS, we cannot access netns_ino:
>
> (struct sock_common).possible_net_t.(struct net *):
>
> typedef struct {
> #ifdef CONFIG_NET_NS
> struct net *net;
> #endif
> } possible_net_t;
>
> And I don't think it would make much sense to allow access to
> netns_dev but not netns_ino.
Right, if CONFIG_NET_NS=n we could just take the pointer to init_net
directly, and not worry about the field. IMHO it'd be preferable to
changing the UAPI based on kernel config, but I don't feel super
strongly.
