[PATCH 3.2 22/92] macvlan: Don't propagate IFF_ALLMULTI changes on down interfaces.

Ben Hutchings
2014-06-07T01:26:28Z

From: Peter Christensen <pch@ordbogen.com>

[ Upstream commit bbeb0eadcf9fe74fb2b9b1a6fea82cd538b1e556 ]

Clearing the IFF_ALLMULTI flag on a down interface could cause an allmulti
overflow on the underlying interface.

Attempting the set IFF_ALLMULTI on the underlying interface would cause an
error and the log message:

"allmulti touches root, set allmulti failed."

Signed-off-by: Peter Christensen <pch@ordbogen.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---
drivers/net/macvlan.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/net/macvlan.c b/drivers/net/macvlan.c
index ab5786b..b74cdf6 100644
--- a/drivers/net/macvlan.c
+++ b/drivers/net/macvlan.c
@@ -391,8 +391,10 @@ static void macvlan_change_rx_flags(struct net_device *dev, int change)
struct macvlan_dev *vlan = netdev_priv(dev);
struct net_device *lowerdev = vlan->lowerdev;

- if (change & IFF_ALLMULTI)
- dev_set_allmulti(lowerdev, dev->flags & IFF_ALLMULTI ? 1 : -1);
+ if (dev->flags & IFF_UP) {
+ if (change & IFF_ALLMULTI)
+ dev_set_allmulti(lowerdev, dev->flags & IFF_ALLMULTI ? 1 : -1);
+ }
}

static void macvlan_set_multicast_list(struct net_device *dev)