Subject: Re: [PATCH net] i40e: Fix adding unsupported cloud filters

From: Simon Horman <[email-masked]>
Date: Sat, 4 Nov 2023 09:43:54 -0400

+ Avinash Dayanand

On Fri, Nov 03, 2023 at 09:42:16PM +0100, Ivan Vecera wrote:
> If a VF tries to add unsupported cloud filter through virchnl
> then i40e_add_del_cloud_filter(_big_buf) returns -ENOTSUPP but
> this error code is stored in 'ret' instead of 'aq_ret' that
> is used as error code sent back to VF. In this scenario where
> one of the mentioned functions fails the value of 'aq_ret'
> is zero so the VF will incorrectly receive a 'success'.
> 
> Use 'aq_ret' to store return value and remove 'ret' local
> variable. Additionally fix the issue when filter allocation
> fails, in this case no notification is sent back to the VF.
> 
> Signed-off-by: Ivan Vecera <[email-masked]>

Hi Ivan,

as a fix targeted at 'net' this probably warrants a fixes tag.
Perhaps the following is appropriate?

Fixes: e284fc280473 ("i40e: Add and delete cloud filter")

The above not withstanding, this change looks good to me.

Reviewed-by: Simon Horman <[email-masked]>

> ---
>  .../net/ethernet/intel/i40e/i40e_virtchnl_pf.c   | 16 +++++++++-------
>  1 file changed, 9 insertions(+), 7 deletions(-)
> 
> diff --git a/drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c b/drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c
> index 08d7edccfb8ddb..3f99eb19824527 100644
> --- a/drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c
> +++ b/drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c
> @@ -3844,7 +3844,7 @@ static int i40e_vc_add_cloud_filter(struct i40e_vf *vf, u8 *msg)
>  	struct i40e_pf *pf = vf->pf;
>  	struct i40e_vsi *vsi = NULL;
>  	int aq_ret = 0;
> -	int i, ret;
> +	int i;
>  
>  	if (!i40e_sync_vf_state(vf, I40E_VF_STATE_ACTIVE)) {
>  		aq_ret = -EINVAL;
> @@ -3868,8 +3868,10 @@ static int i40e_vc_add_cloud_filter(struct i40e_vf *vf, u8 *msg)
>  	}
>  
>  	cfilter = kzalloc(sizeof(*cfilter), GFP_KERNEL);
> -	if (!cfilter)
> -		return -ENOMEM;
> +	if (!cfilter) {
> +		aq_ret = -ENOMEM;
> +		goto err_out;
> +	}
>  
>  	/* parse destination mac address */
>  	for (i = 0; i < ETH_ALEN; i++)
> @@ -3917,13 +3919,13 @@ static int i40e_vc_add_cloud_filter(struct i40e_vf *vf, u8 *msg)
>  
>  	/* Adding cloud filter programmed as TC filter */
>  	if (tcf.dst_port)
> -		ret = i40e_add_del_cloud_filter_big_buf(vsi, cfilter, true);
> +		aq_ret = i40e_add_del_cloud_filter_big_buf(vsi, cfilter, true);
>  	else
> -		ret = i40e_add_del_cloud_filter(vsi, cfilter, true);
> -	if (ret) {
> +		aq_ret = i40e_add_del_cloud_filter(vsi, cfilter, true);
> +	if (aq_ret) {
>  		dev_err(&pf->pdev->dev,
>  			"VF %d: Failed to add cloud filter, err %pe aq_err %s\n",
> -			vf->vf_id, ERR_PTR(ret),
> +			vf->vf_id, ERR_PTR(aq_ret),
>  			i40e_aq_str(&pf->hw, pf->hw.aq.asq_last_status));
>  		goto err_free;
>  	}
> -- 
> 2.41.0
> 
>