[dpdk-dev] [PATCH] net/mlx5: fix sanity check for MPLS-in-GRE

[Matan Azrad]

Hi Koh

From: Yongseok Koh
> Multiple tunnel isn't allowed but MPLS over GRE should be accepted.
> 
> Fixes: a4a5cd21d20a ("net/mlx5: add flow MPLS item")
> 
> Signed-off-by: Yongseok Koh <yskoh at mellanox.com>
> ---
>  drivers/net/mlx5/mlx5_flow.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/net/mlx5/mlx5_flow.c b/drivers/net/mlx5/mlx5_flow.c index
> b7500ec9d6..ca4625b699 100644
> --- a/drivers/net/mlx5/mlx5_flow.c
> +++ b/drivers/net/mlx5/mlx5_flow.c
> @@ -1778,7 +1778,9 @@ mlx5_flow_item_mpls(const struct rte_flow_item
> *item __rte_unused,
>  					  item,
>  					  "protocol filtering not compatible"
>  					  " with MPLS layer");
> -	if (flow->layers & MLX5_FLOW_LAYER_TUNNEL)
> +	/* Multi-tunnel isn't allowed but MPLS over GRE is an exception. */
> +	if (flow->layers & MLX5_FLOW_LAYER_TUNNEL &&
> +	    (flow->layers & MLX5_FLOW_LAYER_GRE) !=

This check is not fully correct because the GRE item must be the last valid item before the mpls, so the next flow

eth / ipv4 / gre / ipv4 / mpls

is not valid.

But the next flows are valid:
eth / ipv4 / gre / mpls
eth / ipv4 / gre / void / mpls
eth / ipv4 / gre / void / void / void / mpls



> MLX5_FLOW_LAYER_GRE)
>  		return rte_flow_error_set(error, ENOTSUP,
>  					  RTE_FLOW_ERROR_TYPE_ITEM,
>  					  item,
> --
> 2.11.0