ixgbe: fix ring assignment issues for SR-IOV and drop cases

This change fixes the fact that we would trigger a null pointer dereference
or specify the wrong ring if the rings were restored.  This change makes
certain that the DROP queue is a static value, and all other rings are
based on the ring offsets for the PF.
Signed-off-by: NAlexander Duyck <alexander.h.duyck@intel.com>
Tested-by: NRoss Brattain <ross.b.brattain@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

drivers/net/ixgbe/ixgbe_ethtool.c

@@ -2677,6 +2677,8 @@ static int ixgbe_add_ethtool_fdir_entry(struct ixgbe_adapter *adapter,
 	/* program filters to filter memory */
 	err = ixgbe_fdir_write_perfect_filter_82599(hw,
 				&input->filter, input->sw_idx,
+				(input->action == IXGBE_FDIR_DROP_QUEUE) ?
+				IXGBE_FDIR_DROP_QUEUE :
 				adapter->rx_ring[input->action]->reg_idx);
 	if (err)
 		goto err_out_w_lock;

drivers/net/ixgbe/ixgbe_main.c

@@ -3757,7 +3757,9 @@ static void ixgbe_fdir_filter_restore(struct ixgbe_adapter *adapter)
 		ixgbe_fdir_write_perfect_filter_82599(hw,
 				&filter->filter,
 				filter->sw_idx,
-						      filter->action);
+				(filter->action == IXGBE_FDIR_DROP_QUEUE) ?
+				IXGBE_FDIR_DROP_QUEUE :
+				adapter->rx_ring[filter->action]->reg_idx);
 	}
 
 	spin_unlock(&adapter->fdir_perfect_lock);