bonding: process the err returned by dev_set_allmulti properly in bond_enslave

When dev_set_promiscuity(1) succeeds but dev_set_allmulti(1) fails,
dev_set_promiscuity(-1) should be done before going to the err path.
Otherwise, dev->promiscuity will leak.

Fixes: 7e1a1ac1 ("bonding: Check return of dev_set_promiscuity/allmulti")
Signed-off-by: NXin Long <lucien.xin@gmail.com>
Acked-by: NAndy Gospodarek <andy@greyhouse.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/bonding/bond_main.c

@@ -1706,8 +1706,11 @@ int bond_enslave(struct net_device *bond_dev, struct net_device *slave_dev,
 		/* set allmulti level to new slave */
 		if (bond_dev->flags & IFF_ALLMULTI) {
 			res = dev_set_allmulti(slave_dev, 1);
-			if (res)
+			if (res) {
+				if (bond_dev->flags & IFF_PROMISC)
+					dev_set_promiscuity(slave_dev, -1);
 				goto err_sysfs_del;
+			}
 		}
 
 		netif_addr_lock_bh(bond_dev);