Re: [PATCH net-next v3 2/3] net: flower: add support for matching cfm fields

[Simon Horman <simon.horman@corigine.com>]

On Mon, Apr 17, 2023 at 11:32:32PM +0200, Zahari Doychev wrote:
> From: Zahari Doychev <zdoychev@maxlinear.com>
> 
> Add support to the tc flower classifier to match based on fields in CFM
> information elements like level and opcode.
> 
> tc filter add dev ens6 ingress protocol 802.1q \
> 	flower vlan_id 698 vlan_ethtype 0x8902 cfm mdl 5 op 46 \
> 	action drop
> 
> Signed-off-by: Zahari Doychev <zdoychev@maxlinear.com>

...

> +static int fl_dump_key_cfm(struct sk_buff *skb,
> +			   struct flow_dissector_key_cfm *key,
> +			   struct flow_dissector_key_cfm *mask)
> +{
> +	struct nlattr *opts;
> +	int err;
> +	u8 mdl;
> +
> +	if (!memchr_inv(mask, 0, sizeof(mask)))

Perhaps this should be sizeof(*mask)

With that fixed feel free to add,

Reviewed-by: Simon Horman <simon.horman@corigine.com>


> +		return 0;
> +
> +	opts = nla_nest_start(skb, TCA_FLOWER_KEY_CFM);
> +	if (!opts)
> +		return -EMSGSIZE;
> +
> +	if (FIELD_GET(FLOW_DIS_CFM_MDL_MASK, mask->mdl_ver)) {
> +		mdl = FIELD_GET(FLOW_DIS_CFM_MDL_MASK, key->mdl_ver);
> +		err = nla_put_u8(skb, TCA_FLOWER_KEY_CFM_MD_LEVEL, mdl);
> +		if (err)
> +			goto err_cfm_opts;
> +	}
> +
> +	if (mask->opcode) {
> +		err = nla_put_u8(skb, TCA_FLOWER_KEY_CFM_OPCODE, key->opcode);
> +		if (err)
> +			goto err_cfm_opts;
> +	}
> +
> +	nla_nest_end(skb, opts);
> +
> +	return 0;
> +
> +err_cfm_opts:
> +	nla_nest_cancel(skb, opts);
> +	return err;
> +}

...