[PATCH] net/sfc: enforce fate action in transfer flow rules

[Ivan Malov <ivan.malov@arknetworks.am>]

According to DPDK documentation, not specifying a
fate action in a flow rule results in undefined
behaviour. Define right behaviour in the driver.

Fixes: 0839236d0391 ("net/sfc: support flow action drop in transfer rules")
Cc: stable@dpdk.org

Signed-off-by: Ivan Malov <ivan.malov@arknetworks.am>
Reviewed-by: Viacheslav Galaktionov <viacheslav.galaktionov@arknetworks.am>
Reviewed-by: Andy Moreton <amoreton@xilinx.com>
---
 drivers/net/sfc/sfc_mae.c | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/drivers/net/sfc/sfc_mae.c b/drivers/net/sfc/sfc_mae.c
index c254562696..3daeed81b9 100644
--- a/drivers/net/sfc/sfc_mae.c
+++ b/drivers/net/sfc/sfc_mae.c
@@ -3910,6 +3910,21 @@ sfc_mae_rule_parse_actions(struct sfc_adapter *sa,
 		SFC_ASSERT(B_FALSE);
 	}
 
+	/*
+	 * A DPDK flow entry must specify a fate action, which the parser
+	 * converts into a DELIVER action in a libefx action set. An
+	 * attempt to replace the action in the action set should
+	 * fail. If it succeeds then report an error, as the
+	 * parsed flow entry did not contain a fate action.
+	 */
+	rc = efx_mae_action_set_populate_drop(ctx.spec);
+	if (rc == 0) {
+		rc = rte_flow_error_set(error, EINVAL,
+					RTE_FLOW_ERROR_TYPE_ACTION, NULL,
+					"no fate action found");
+		goto fail_check_fate_action;
+	}
+
 	spec_mae->action_set = sfc_mae_action_set_attach(sa, &ctx);
 	if (spec_mae->action_set != NULL) {
 		sfc_mae_mac_addr_del(sa, ctx.src_mac);
@@ -3926,6 +3941,7 @@ sfc_mae_rule_parse_actions(struct sfc_adapter *sa,
 	return 0;
 
 fail_action_set_add:
+fail_check_fate_action:
 fail_workaround_tunnel_delivery:
 fail_nb_count:
 	sfc_mae_encap_header_del(sa, ctx.encap_header);
-- 
2.17.1