[net,V2] net/mlx4: Fix the check in attaching steering rules

From: Talat Batheesh <talatb@mellanox.com>

Our previous patch (cited below) introduced a regression
for RAW Eth QPs.

Fix it by checking if the QP number provided by user-space
exists, hence allowing steering rules to be added for valid
QPs only.

Fixes: 89c557687a32 ("net/mlx4_en: Avoid adding steering rules with ...")
Reported-by: Or Gerlitz <gerlitz.or@gmail.com>
Signed-off-by: Talat Batheesh <talatb@mellanox.com>
Signed-off-by: Tariq Toukan <tariqt@mellanox.com>
Acked-by: Or Gerlitz <ogerlitz@mellanox.com>
Reviewed-by: Leon Romanovsky <leonro@mellanox.com>
---
v2:
* Removed unnecessary EXPORT_SYMBOL_GPL.

 drivers/net/ethernet/mellanox/mlx4/en_ethtool.c |  3 +--
 drivers/net/ethernet/mellanox/mlx4/qp.c         | 13 +++++++++++++
 include/linux/mlx4/qp.h                         |  1 +
 3 files changed, 15 insertions(+), 2 deletions(-)

On 25/05/2017 4:21 PM, Tariq Toukan wrote:
> From: Talat Batheesh <talatb@mellanox.com>
>
> Our previous patch (cited below) introduced a regression
> for RAW Eth QPs.
>
> Fix it by checking if the QP number provided by user-space
> exists, hence allowing steering rules to be added for valid
> QPs only.
>
> Fixes: 89c557687a32 ("net/mlx4_en: Avoid adding steering rules with ...")
> Reported-by: Or Gerlitz <gerlitz.or@gmail.com>
> Signed-off-by: Talat Batheesh <talatb@mellanox.com>
> Signed-off-by: Tariq Toukan <tariqt@mellanox.com>
> Acked-by: Or Gerlitz <ogerlitz@mellanox.com>
> Reviewed-by: Leon Romanovsky <leonro@mellanox.com>
> ---
> v2:
> * Removed unnecessary EXPORT_SYMBOL_GPL.

My bad, this doesn't work.
Please ignore patch.

>
>   drivers/net/ethernet/mellanox/mlx4/en_ethtool.c |  3 +--
>   drivers/net/ethernet/mellanox/mlx4/qp.c         | 13 +++++++++++++
>   include/linux/mlx4/qp.h                         |  1 +
>   3 files changed, 15 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/net/ethernet/mellanox/mlx4/en_ethtool.c b/drivers/net/ethernet/mellanox/mlx4/en_ethtool.c
> index ae5fdc2df654..00a7cd3dcc2e 100644
> --- a/drivers/net/ethernet/mellanox/mlx4/en_ethtool.c
> +++ b/drivers/net/ethernet/mellanox/mlx4/en_ethtool.c
> @@ -1562,8 +1562,7 @@ static int mlx4_en_flow_replace(struct net_device *dev,
>   		qpn = priv->drop_qp.qpn;
>   	else if (cmd->fs.ring_cookie & EN_ETHTOOL_QP_ATTACH) {
>   		qpn = cmd->fs.ring_cookie & (EN_ETHTOOL_QP_ATTACH - 1);
> -		if (qpn < priv->rss_map.base_qpn ||
> -		    qpn >= priv->rss_map.base_qpn + priv->rx_ring_num) {
> +		if (!mlx4_qp_lookup(priv->mdev->dev, qpn)) {
>   			en_warn(priv, "rxnfc: QP (0x%x) doesn't exist\n", qpn);
>   			return -EINVAL;
>   		}
> diff --git a/drivers/net/ethernet/mellanox/mlx4/qp.c b/drivers/net/ethernet/mellanox/mlx4/qp.c
> index 2d6abd4662b1..ad92d2311478 100644
> --- a/drivers/net/ethernet/mellanox/mlx4/qp.c
> +++ b/drivers/net/ethernet/mellanox/mlx4/qp.c
> @@ -384,6 +384,19 @@ static void mlx4_qp_free_icm(struct mlx4_dev *dev, int qpn)
>   		__mlx4_qp_free_icm(dev, qpn);
>   }
>   
> +struct mlx4_qp *mlx4_qp_lookup(struct mlx4_dev *dev, u32 qpn)
> +{
> +	struct mlx4_qp_table *qp_table = &mlx4_priv(dev)->qp_table;
> +	struct mlx4_qp *qp;
> +
> +	spin_lock(&qp_table->lock);
> +
> +	qp = __mlx4_qp_lookup(dev, qpn);
> +
> +	spin_unlock(&qp_table->lock);
> +	return qp;
> +}
> +
>   int mlx4_qp_alloc(struct mlx4_dev *dev, int qpn, struct mlx4_qp *qp, gfp_t gfp)
>   {
>   	struct mlx4_priv *priv = mlx4_priv(dev);
> diff --git a/include/linux/mlx4/qp.h b/include/linux/mlx4/qp.h
> index b4ee8f62ce8d..8e2828d48d7f 100644
> --- a/include/linux/mlx4/qp.h
> +++ b/include/linux/mlx4/qp.h
> @@ -470,6 +470,7 @@ struct mlx4_update_qp_params {
>   	u16	rate_val;
>   };
>   
> +struct mlx4_qp *mlx4_qp_lookup(struct mlx4_dev *dev, u32 qpn);
>   int mlx4_update_qp(struct mlx4_dev *dev, u32 qpn,
>   		   enum mlx4_update_qp_attr attr,
>   		   struct mlx4_update_qp_params *params);