Re: [dpdk-stable] [PATCH v2] net/mlx5: fix incorrect pointer operation in meter

[Slava Ovsiienko <viacheslavo@mellanox.com>]

> -----Original Message-----
> From: Suanming Mou <suanmingm@mellanox.com>
> Sent: Wednesday, January 8, 2020 12:41
> To: Matan Azrad <matan@mellanox.com>; Shahaf Shuler
> <shahafs@mellanox.com>; Slava Ovsiienko <viacheslavo@mellanox.com>
> Cc: dev@dpdk.org; xiangxia.m.yue@gmail.com; Raslan Darawsheh
> <rasland@mellanox.com>; stable@dpdk.org
> Subject: [PATCH v2] net/mlx5: fix incorrect pointer operation in meter
> 
> The meter suffix flow item pointer restore is not correct to decrease a fixed
> value. The incorrect operation will cause incorrect match to the meter suffix
> flow, the flow create will fail once the magic number in the wrong offset
> memory start with RTE_FLOW_ITEM_TYPE_END.
> The pointer should decrease the real offset it increases.
> 
> Set the decrease value to the real offset the pointer increases to fix the issue.
> 
> Fixes: 9ea9b049a960 ("net/mlx5: split meter flow")
> Cc: stable@dpdk.org
> 
> Signed-off-by: Suanming Mou <suanmingm@mellanox.com>
> Reported-by: Tonghao Zhang <xiangxia.m.yue@gmail.com>
Acked-by: Viacheslav Ovsiienko <viacheslavo@mellanox.com>

> ---
> 
> v2: commit message adjust.
> 
> ---
>  drivers/net/mlx5/mlx5_flow.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/net/mlx5/mlx5_flow.c b/drivers/net/mlx5/mlx5_flow.c
> index cb9d265..52ffcb2 100644
> --- a/drivers/net/mlx5/mlx5_flow.c
> +++ b/drivers/net/mlx5/mlx5_flow.c
> @@ -4037,7 +4037,7 @@ uint32_t mlx5_flow_adjust_priority(struct
> rte_eth_dev *dev, int32_t priority,
>  			sfx_items++;
>  		}
>  		sfx_items->type = RTE_FLOW_ITEM_TYPE_END;
> -		sfx_items -= METER_SUFFIX_ITEM;
> +		sfx_items -= sfx_port_id_item ? 2 : 1;
>  		/* Setting the sfx group atrr. */
>  		sfx_attr.group = sfx_attr.transfer ?
>  				(MLX5_FLOW_TABLE_LEVEL_SUFFIX - 1) :
> --
> 1.8.3.1