[dpdk-stable] [PATCH v2 1/6] net/mlx5: check for a field size in modify field action

[Alexander Kozyrev]

Add a validation check to make sure that the specified width
for MODIFY_FIELD RTE action is not bigger than a field size.

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

Signed-off-by: Alexander Kozyrev <akozyrev at nvidia.com>
---
 drivers/net/mlx5/mlx5_flow_dv.c | 23 ++++++++++++++++-------
 1 file changed, 16 insertions(+), 7 deletions(-)

diff --git a/drivers/net/mlx5/mlx5_flow_dv.c b/drivers/net/mlx5/mlx5_flow_dv.c
index 23e5849783..84e1bb6892 100644
--- a/drivers/net/mlx5/mlx5_flow_dv.c
+++ b/drivers/net/mlx5/mlx5_flow_dv.c
@@ -4608,9 +4608,22 @@ flow_dv_validate_action_modify_field(const uint64_t action_flags,
 	if (ret)
 		return ret;
 
+	if (action_modify_field->width == 0)
+		return rte_flow_error_set(error, EINVAL,
+					RTE_FLOW_ERROR_TYPE_ACTION,
+					NULL,
+					"no bits are requested to be modified");
+	else if (action_modify_field->width > dst_width ||
+		 action_modify_field->width > src_width)
+		return rte_flow_error_set(error, EINVAL,
+					RTE_FLOW_ERROR_TYPE_ACTION,
+					NULL,
+					"cannot modify more bits than"
+					" the width of a field");
 	if (action_modify_field->dst.field != RTE_FLOW_FIELD_VALUE &&
 	    action_modify_field->dst.field != RTE_FLOW_FIELD_POINTER) {
-		if (action_modify_field->dst.offset >= dst_width ||
+		if ((action_modify_field->dst.offset +
+		     action_modify_field->width > dst_width) ||
 		    (action_modify_field->dst.offset % 32))
 			return rte_flow_error_set(error, EINVAL,
 						RTE_FLOW_ERROR_TYPE_ACTION,
@@ -4626,7 +4639,8 @@ flow_dv_validate_action_modify_field(const uint64_t action_flags,
 	}
 	if (action_modify_field->src.field != RTE_FLOW_FIELD_VALUE &&
 	    action_modify_field->src.field != RTE_FLOW_FIELD_POINTER) {
-		if (action_modify_field->src.offset >= src_width ||
+		if ((action_modify_field->src.offset +
+		     action_modify_field->width > src_width) ||
 		    (action_modify_field->src.offset % 32))
 			return rte_flow_error_set(error, EINVAL,
 						RTE_FLOW_ERROR_TYPE_ACTION,
@@ -4640,11 +4654,6 @@ flow_dv_validate_action_modify_field(const uint64_t action_flags,
 						NULL,
 						"cannot copy from inner headers");
 	}
-	if (action_modify_field->width == 0)
-		return rte_flow_error_set(error, EINVAL,
-						RTE_FLOW_ERROR_TYPE_ACTION,
-						NULL,
-						"width is required for modify action");
 	if (action_modify_field->dst.field ==
 	    action_modify_field->src.field)
 		return rte_flow_error_set(error, EINVAL,
-- 
2.24.1