igb: Fix removal of unicast MAC filters of VFs

[ Upstream commit 584af82 ]

Move checking condition of VF MAC filter before clearing
or adding MAC filter to VF to prevent potential blackout caused
by removal of necessary and working VF's MAC filter.

Fixes: 1b8b062 ("igb: add VF trust infrastructure")
Signed-off-by: Karen Sornek <[email protected]>
Tested-by: Konrad Jankowski <[email protected]>
Signed-off-by: Tony Nguyen <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>

Author: ksornek

drivers/net/ethernet/intel/igb/igb_main.c

@@ -7641,6 +7641,20 @@ static int igb_set_vf_mac_filter(struct igb_adapter *adapter, const int vf,
 	struct vf_mac_filter *entry = NULL;
 	int ret = 0;
 
+	if ((vf_data->flags & IGB_VF_FLAG_PF_SET_MAC) &&
+	    !vf_data->trusted) {
+		dev_warn(&pdev->dev,
+			 "VF %d requested MAC filter but is administratively denied\n",
+			  vf);
+		return -EINVAL;
+	}
+	if (!is_valid_ether_addr(addr)) {
+		dev_warn(&pdev->dev,
+			 "VF %d attempted to set invalid MAC filter\n",
+			  vf);
+		return -EINVAL;
+	}
+
 	switch (info) {
 	case E1000_VF_MAC_FILTER_CLR:
 		/* remove all unicast MAC filters related to the current VF */
@@ -7654,20 +7668,6 @@ static int igb_set_vf_mac_filter(struct igb_adapter *adapter, const int vf,
 		}
 		break;
 	case E1000_VF_MAC_FILTER_ADD:
-		if ((vf_data->flags & IGB_VF_FLAG_PF_SET_MAC) &&
-		    !vf_data->trusted) {
-			dev_warn(&pdev->dev,
-				 "VF %d requested MAC filter but is administratively denied\n",
-				 vf);
-			return -EINVAL;
-		}
-		if (!is_valid_ether_addr(addr)) {
-			dev_warn(&pdev->dev,
-				 "VF %d attempted to set invalid MAC filter\n",
-				 vf);
-			return -EINVAL;
-		}
-
 		/* try to find empty slot in the list */
 		list_for_each(pos, &adapter->vf_macs.l) {
 			entry = list_entry(pos, struct vf_mac_filter, l);