net/mlx5: E-Switch, Fix some error pointer dereferences

We can't leave "counter" set to an error pointer.  Otherwise either it
will lead to an error pointer dereference later in the function or it
leads to an error pointer dereference when we call mlx5_fc_destroy().

Fixes: 07bab95 ("net/mlx5: E-Switch, Refactor eswitch ingress acl codes")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>

Author: Dan Carpenter

drivers/net/ethernet/mellanox/mlx5/core/esw/acl/ingress_lgcy.c

@@ -162,10 +162,12 @@ int esw_acl_ingress_lgcy_setup(struct mlx5_eswitch *esw,
 
 	if (MLX5_CAP_ESW_INGRESS_ACL(esw->dev, flow_counter)) {
 		counter = mlx5_fc_create(esw->dev, false);
-		if (IS_ERR(counter))
+		if (IS_ERR(counter)) {
 			esw_warn(esw->dev,
 				 "vport[%d] configure ingress drop rule counter failed\n",
 				 vport->vport);
+			counter = NULL;
+		}
 		vport->ingress.legacy.drop_counter = counter;
 	}
 
@@ -272,7 +274,7 @@ void esw_acl_ingress_lgcy_cleanup(struct mlx5_eswitch *esw,
 	esw_acl_ingress_table_destroy(vport);
 
 clean_drop_counter:
-	if (!IS_ERR_OR_NULL(vport->ingress.legacy.drop_counter)) {
+	if (vport->ingress.legacy.drop_counter) {
 		mlx5_fc_destroy(esw->dev, vport->ingress.legacy.drop_counter);
 		vport->ingress.legacy.drop_counter = NULL;
 	}