[dpdk-stable] [PATCH] net/mlx5: fix pop VLAN with decap action validate

[Dekel Peled]

The combination of decap action followed by pop VLAN action is not
fully validated in existing code.

This patch updates the validation function of pop vlan action.
Pop VLAN with preceding Decap requires inner header with VLAN.
Pop VLAN without preceding Decap requires outer header with VLAN.

Fixes: b41e47da2592 ("net/mlx5: support pop flow action on VLAN header")
Cc: stable at dpdk.org

Signed-off-by: Dekel Peled <dekelp at mellanox.com>
Acked-by: Matan Azrad <matan at mellanox.com>
---
 drivers/net/mlx5/mlx5_flow_dv.c | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/drivers/net/mlx5/mlx5_flow_dv.c b/drivers/net/mlx5/mlx5_flow_dv.c
index 8b5b683..69c2c72 100644
--- a/drivers/net/mlx5/mlx5_flow_dv.c
+++ b/drivers/net/mlx5/mlx5_flow_dv.c
@@ -1839,7 +1839,17 @@ struct field_modify_info modify_tcp[] = {
 					  RTE_FLOW_ERROR_TYPE_ACTION, action,
 					  "no support for multiple VLAN "
 					  "actions");
-	if (!(item_flags & MLX5_FLOW_LAYER_OUTER_VLAN))
+	/* Pop VLAN with preceding Decap requires inner header with VLAN. */
+	if ((action_flags & MLX5_FLOW_ACTION_DECAP) &&
+	    !(item_flags & MLX5_FLOW_LAYER_INNER_VLAN))
+		return rte_flow_error_set(error, ENOTSUP,
+					  RTE_FLOW_ERROR_TYPE_UNSPECIFIED,
+					  NULL,
+					  "cannot pop vlan after decap without "
+					  "match on inner vlan in the flow");
+	/* Pop VLAN without preceding Decap requires outer header with VLAN. */
+	if (!(action_flags & MLX5_FLOW_ACTION_DECAP) &&
+	    !(item_flags & MLX5_FLOW_LAYER_OUTER_VLAN))
 		return rte_flow_error_set(error, ENOTSUP,
 					  RTE_FLOW_ERROR_TYPE_UNSPECIFIED,
 					  NULL,
-- 
1.8.3.1