ixgbevf: fix error code path when setting MAC address

BugLink: http://bugs.launchpad.net/bugs/1616677

Return error when a MAC address change is rejected by the PF.

This will prevent the user from modifying the MAC address when
that operation is not permitted.
Signed-off-by: Emil Tantilov <emil.s.tantilov@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
(cherry picked from commit 32ca6868)
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>
Acked-by: Brad Figg <brad.figg@canonical.com>
Acked-by: Kamal Mostafa <kamal@canonical.com>

drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c

@@ -3695,19 +3695,23 @@ static int ixgbevf_set_mac(struct net_device *netdev, void *p)
 	struct ixgbevf_adapter *adapter = netdev_priv(netdev);
 	struct ixgbe_hw *hw = &adapter->hw;
 	struct sockaddr *addr = p;
+	int err;
 
 	if (!is_valid_ether_addr(addr->sa_data))
 		return -EADDRNOTAVAIL;
 
-	ether_addr_copy(netdev->dev_addr, addr->sa_data);
-	ether_addr_copy(hw->mac.addr, addr->sa_data);
-
 	spin_lock_bh(&adapter->mbx_lock);
 
-	hw->mac.ops.set_rar(hw, 0, hw->mac.addr, 0);
+	err = hw->mac.ops.set_rar(hw, 0, addr->sa_data, 0);
 
 	spin_unlock_bh(&adapter->mbx_lock);
 
+	if (err)
+		return -EPERM;
+
+	ether_addr_copy(hw->mac.addr, addr->sa_data);
+	ether_addr_copy(netdev->dev_addr, addr->sa_data);
+
 	return 0;
 }
 

drivers/net/ethernet/intel/ixgbevf/vf.c

@@ -408,8 +408,10 @@ static s32 ixgbevf_set_rar_vf(struct ixgbe_hw *hw, u32 index, u8 *addr,
 
 	/* if nacked the address was rejected, use "perm_addr" */
 	if (!ret_val &&
-	    (msgbuf[0] == (IXGBE_VF_SET_MAC_ADDR | IXGBE_VT_MSGTYPE_NACK)))
+	    (msgbuf[0] == (IXGBE_VF_SET_MAC_ADDR | IXGBE_VT_MSGTYPE_NACK))) {
 		ixgbevf_get_mac_addr_vf(hw, hw->mac.addr);
+		return IXGBE_ERR_MBX;
+	}
 
 	return ret_val;
 }