net/mlx5e: Properly handle FW errors while adding TC rules

When the firmware returns an error (common example is an attempt to
add twice the same rule which is refused by the some FWs), we are not
properly derefing/cleaning few resources allocated on the way.
Examples are vport vlan deref under eswitch vlan offloads, and encap
entry/neighbour deref under eswitch encapsulation offloads, fix that.

Fixes: a54e20b4 ('net/mlx5e: Add basic TC tunnel set action for SRIOV offloads')
Fixes: 8b32580d ('net/mlx5e: Add TC vlan action for SRIOV offloads')
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Reviewed-by: Roi Dayan <roid@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/mellanox/mlx5/core/en_tc.c

@@ -161,15 +161,21 @@ static void mlx5e_detach_encap(struct mlx5e_priv *priv,
 	}
 }
 
+/* we get here also when setting rule to the FW failed, etc. It means that the
+ * flow rule itself might not exist, but some offloading related to the actions
+ * should be cleaned.
+ */
 static void mlx5e_tc_del_flow(struct mlx5e_priv *priv,
 			      struct mlx5e_tc_flow *flow)
 {
 	struct mlx5_eswitch *esw = priv->mdev->priv.eswitch;
 	struct mlx5_fc *counter = NULL;
 
+	if (!IS_ERR(flow->rule)) {
 		counter = mlx5_flow_rule_counter(flow->rule);
-
 		mlx5_del_flow_rules(flow->rule);
+		mlx5_fc_destroy(priv->mdev, counter);
+	}
 
 	if (esw && esw->mode == SRIOV_OFFLOADS) {
 		mlx5_eswitch_del_vlan_action(esw, flow->attr);
@@ -177,8 +183,6 @@ static void mlx5e_tc_del_flow(struct mlx5e_priv *priv,
 			mlx5e_detach_encap(priv, flow);
 	}
 
-	mlx5_fc_destroy(priv->mdev, counter);
-
 	if (!mlx5e_tc_num_filters(priv) && (priv->fs.tc.t)) {
 		mlx5_destroy_flow_table(priv->fs.tc.t);
 		priv->fs.tc.t = NULL;
@@ -1017,7 +1021,7 @@ int mlx5e_configure_flower(struct mlx5e_priv *priv, __be16 protocol,
 
 	if (IS_ERR(flow->rule)) {
 		err = PTR_ERR(flow->rule);
-		goto err_free;
+		goto err_del_rule;
 	}
 
 	err = rhashtable_insert_fast(&tc->ht, &flow->node,
@@ -1028,7 +1032,7 @@ int mlx5e_configure_flower(struct mlx5e_priv *priv, __be16 protocol,
 	goto out;
 
 err_del_rule:
-	mlx5_del_flow_rules(flow->rule);
+	mlx5e_tc_del_flow(priv, flow);
 
 err_free:
 	kfree(flow);