[dpdk-stable] [PATCH v2 6/6] net/mlx5: reject VXLAN ID's modifications

[Alexander Kozyrev <akozyrev@nvidia.com>]

Modification of the 802.1Q Tag Identificator, VXLAN Network
Identificator or GENEVE Network Identificator is not supported.
Reject attempt to modify these fields via the MODIFY_FIELD
action and document this mlx5 driver limitation.

Fixes: 641dbe4fb0 ("net/mlx5: support modify field flow action")
Cc: stable@dpdk.org

Signed-off-by: Alexander Kozyrev <akozyrev@nvidia.com>
---
 doc/guides/nics/mlx5.rst        |  1 +
 drivers/net/mlx5/mlx5_flow_dv.c | 21 +++++++++++++++++++++
 2 files changed, 22 insertions(+)

diff --git a/doc/guides/nics/mlx5.rst b/doc/guides/nics/mlx5.rst
index a2cfc51b2a..92369fa5ee 100644
--- a/doc/guides/nics/mlx5.rst
+++ b/doc/guides/nics/mlx5.rst
@@ -383,6 +383,7 @@ Limitations
 
   - Supports the 'set' operation only for ``RTE_FLOW_ACTION_TYPE_MODIFY_FIELD`` action.
   - Modification of an arbitrary place in a packet via the special ``RTE_FLOW_FIELD_START`` Field ID is not supported.
+  - Modification of the 802.1Q Tag, VXLAN Network or GENEVE Network ID's is not supported.
   - Encapsulation levels are not supported, can modify outermost header fields only.
   - Offsets must be 32-bits aligned, cannot skip past the boundary of a field.
 
diff --git a/drivers/net/mlx5/mlx5_flow_dv.c b/drivers/net/mlx5/mlx5_flow_dv.c
index ecabf63f53..223a7d0e36 100644
--- a/drivers/net/mlx5/mlx5_flow_dv.c
+++ b/drivers/net/mlx5/mlx5_flow_dv.c
@@ -4650,6 +4650,27 @@ flow_dv_validate_action_modify_field(struct rte_eth_dev *dev,
 				NULL,
 				"modifications of an arbitrary"
 				" place in a packet is not supported");
+	if (action_modify_field->dst.field == RTE_FLOW_FIELD_VLAN_TYPE ||
+	    action_modify_field->src.field == RTE_FLOW_FIELD_VLAN_TYPE)
+		return rte_flow_error_set(error, EINVAL,
+				RTE_FLOW_ERROR_TYPE_ACTION,
+				NULL,
+				"modifications of the 802.1Q Tag"
+				" Identifier is not supported");
+	if (action_modify_field->dst.field == RTE_FLOW_FIELD_VXLAN_VNI ||
+	    action_modify_field->src.field == RTE_FLOW_FIELD_VXLAN_VNI)
+		return rte_flow_error_set(error, EINVAL,
+				RTE_FLOW_ERROR_TYPE_ACTION,
+				NULL,
+				"modifications of the VXLAN Network"
+				" Identifier is not supported");
+	if (action_modify_field->dst.field == RTE_FLOW_FIELD_GENEVE_VNI ||
+	    action_modify_field->src.field == RTE_FLOW_FIELD_GENEVE_VNI)
+		return rte_flow_error_set(error, EINVAL,
+				RTE_FLOW_ERROR_TYPE_ACTION,
+				NULL,
+				"modifications of the GENEVE Network"
+				" Identifier is not supported");
 	if (action_modify_field->dst.field == RTE_FLOW_FIELD_MARK ||
 	    action_modify_field->src.field == RTE_FLOW_FIELD_MARK) {
 		if (config->dv_xmeta_en == MLX5_XMETA_MODE_LEGACY ||
-- 
2.24.1