Link dumps can return results from a target namespace. If the namespace id
is invalid, then the dump request should fail if get_target_net fails
rather than continuing with a dump of the current namespace.
Fixes: 79e1ad148c844 ("rtnetlink: use netnsid to query interface")
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
                if (tb[IFLA_IF_NETNSID]) {
                        netnsid = nla_get_s32(tb[IFLA_IF_NETNSID]);
                        tgt_net = get_target_net(skb->sk, netnsid);
-                       if (IS_ERR(tgt_net)) {
-                               tgt_net = net;
-                               netnsid = -1;
-                       }
+                       if (IS_ERR(tgt_net))
+                               return PTR_ERR(tgt_net);
                }
 
                if (tb[IFLA_EXT_MASK])