[PATCH] net/mlx5: fix RSS validation for meter hierarchy

[Bing Zhao <bingz@nvidia.com>]

In a meter hierarchy, all the meters are marked with having RSS if
the final meter's termination action is RSS.

When validating a flow rule with meter hierarchy, the RSS action
should not be fetched from the current meter if it is not the final
one.

The fate action union is next meter ID instead of the pointer to the
RSS action. By using the final meter in the hierarchy, the flow rule
validation will succeed without any crash caused by the invalide RSS
action pointer access.

Fixes: 1ce19ab1f43b ("net/mlx5: fix RSS validation with meter policy")
Cc: stable@dpdk.org

Signed-off-by: Bing Zhao <bingz@nvidia.com>
Reviewed-by: Li Zhang <lizh@nvidia.com>
Reviewed-by: Shun Hao <shunh@nvidia.com>
Acked-by: Matan Azrad <matan@nvidia.com>
---
 drivers/net/mlx5/mlx5_flow_dv.c | 16 ++++++++++++----
 1 file changed, 12 insertions(+), 4 deletions(-)

diff --git a/drivers/net/mlx5/mlx5_flow_dv.c b/drivers/net/mlx5/mlx5_flow_dv.c
index 2f03e59f9c..f5356418fa 100644
--- a/drivers/net/mlx5/mlx5_flow_dv.c
+++ b/drivers/net/mlx5/mlx5_flow_dv.c
@@ -5254,13 +5254,21 @@ mlx5_flow_validate_action_meter(struct rte_eth_dev *dev,
 						"Flow and meter policy "
 						"have different src port.");
 		} else if (mtr_policy->is_rss) {
-			struct mlx5_meter_policy_action_container *acg =
-				&mtr_policy->act_cnt[RTE_COLOR_GREEN];
-			struct mlx5_meter_policy_action_container *acy =
-				&mtr_policy->act_cnt[RTE_COLOR_YELLOW];
+			struct mlx5_flow_meter_policy *fp;
+			struct mlx5_meter_policy_action_container *acg;
+			struct mlx5_meter_policy_action_container *acy;
 			const struct rte_flow_action *rss_act;
 			int ret;
 
+			fp = mlx5_flow_meter_hierarchy_get_final_policy(dev,
+								mtr_policy);
+			if (fp == NULL)
+				return rte_flow_error_set(error, EINVAL,
+					RTE_FLOW_ERROR_TYPE_ACTION, NULL,
+						  "Unable to get the final "
+						  "policy in the hierarchy");
+			acg = &fp->act_cnt[RTE_COLOR_GREEN];
+			acy = &fp->act_cnt[RTE_COLOR_YELLOW];
 			MLX5_ASSERT(acg->fate_action ==
 				    MLX5_FLOW_FATE_SHARED_RSS ||
 				    acy->fate_action ==
-- 
2.26.2