net: allow macvlans to move to net namespace

[ Upstream commit 0d0162e7 ]

I cannot move a macvlan interface created on top of a bonding interface
to a different namespace:

% ip netns add dummy0
% ip link add link bond0 mac0 type macvlan
% ip link set mac0 netns dummy0
RTNETLINK answers: Invalid argument
%

The problem seems to be that commit f9399814 ("bonding: Don't allow
bond devices to change network namespaces.") sets NETIF_F_NETNS_LOCAL
on bonding interfaces, and commit 797f87f8 ("macvlan: fix netdev
feature propagation from lower device") causes macvlan interfaces
to inherit its features from the lower device.

NETIF_F_NETNS_LOCAL should not be inherited from the lower device
by a macvlan.
Patch tested on 3.16.
Signed-off-by: Francesco Ruggeri <fruggeri@arista.com>
Acked-by: Cong Wang <cwang@twopensource.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/net/macvlan.c

@@ -800,6 +800,7 @@ static netdev_features_t macvlan_fix_features(struct net_device *dev,
 					     features,
 					     mask);
 	features |= ALWAYS_ON_FEATURES;
+	features &= ~NETIF_F_NETNS_LOCAL;
 
 	return features;
 }