[PATCH net-next 7/8] macvlan: Check return of dev_set_allmulti

[Wang Chen <wangchen@cn.fujitsu.com>]

allmulti might overflow.
Commit: "netdevice: Fix promiscuity and allmulti overflow" in net-next makes
dev_set_promiscuity/allmulti return error number if overflow happened.

Here, we check the positive increment for allmulti to get error return.

Signed-off-by: Wang Chen <wangchen@cn.fujitsu.com>
---
 drivers/net/macvlan.c |    9 +++++++--
 1 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/drivers/net/macvlan.c b/drivers/net/macvlan.c
index c36a03a..b0ed18f 100644
--- a/drivers/net/macvlan.c
+++ b/drivers/net/macvlan.c
@@ -190,8 +190,13 @@ static int macvlan_open(struct net_device *dev)
 	err = dev_unicast_add(lowerdev, dev->dev_addr, ETH_ALEN);
 	if (err < 0)
 		return err;
-	if (dev->flags & IFF_ALLMULTI)
-		dev_set_allmulti(lowerdev, 1);
+	if (dev->flags & IFF_ALLMULTI) {
+		err = dev_set_allmulti(lowerdev, 1);
+		if (err < 0) {
+			dev_unicast_delete(lowerdev, dev->dev_addr, ETH_ALEN);
+			return err;
+		}
+	}
 
 	hlist_add_head_rcu(&vlan->hlist, &port->vlan_hash[dev->dev_addr[5]]);
 	return 0;
-- 
1.5.3.4