From: Cong Wang > Sent: 29 May 2021 20:15 > > On Fri, May 28, 2021 at 11:08 PM Changbin Du <changbin.du@xxxxxxxxx> wrote: > > diff --git a/net/socket.c b/net/socket.c > > index 27e3e7d53f8e..644b46112d35 100644 > > --- a/net/socket.c > > +++ b/net/socket.c > > @@ -1149,11 +1149,15 @@ static long sock_ioctl(struct file *file, unsigned cmd, unsigned long arg) > > mutex_unlock(&vlan_ioctl_mutex); > > break; > > case SIOCGSKNS: > > +#ifdef CONFIG_NET_NS > > err = -EPERM; > > if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) > > break; > > > > err = open_related_ns(&net->ns, get_net_ns); > > +#else > > + err = -ENOTSUPP; > > +#endif > > I wonder if it is easier if we just reject ns->ops==NULL case > in open_related_ns(). For 1) we can save an ugly #ifdef here; > 2) drivers/net/tun.c has the same bugs. If CONFIG_NET_NS is unset then why not make both ns_capable() and open_related_ns() unconditionally return -ENOTSUPP? David - Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK Registration No: 1397386 (Wales)
