Re: [patch net-next v4 8/9] devlink: add a command to set notification filter and use it for multicasts

[Jiri Pirko <jiri@resnulli.us>]

Mon, Nov 27, 2023 at 04:40:22PM CET, przemyslaw.kitszel@intel.com wrote:
>On 11/23/23 19:15, Jiri Pirko wrote:
>> From: Jiri Pirko <jiri@nvidia.com>
>> 

[...]


>> diff --git a/net/devlink/netlink.c b/net/devlink/netlink.c
>> index fa9afe3e6d9b..33a8e51dea68 100644
>> --- a/net/devlink/netlink.c
>> +++ b/net/devlink/netlink.c
>> @@ -17,6 +17,79 @@ static const struct genl_multicast_group devlink_nl_mcgrps[] = {
>>   	[DEVLINK_MCGRP_CONFIG] = { .name = DEVLINK_GENL_MCGRP_CONFIG_NAME },
>>   };
>> +int devlink_nl_notify_filter_set_doit(struct sk_buff *skb,
>> +				      struct genl_info *info)
>> +{
>> +	struct nlattr **attrs = info->attrs;
>> +	struct devlink_obj_desc *flt;
>> +	size_t data_offset = 0;
>> +	size_t data_size = 0;
>> +	char *pos;
>> +
>> +	if (attrs[DEVLINK_ATTR_BUS_NAME])
>> +		data_size += nla_len(attrs[DEVLINK_ATTR_BUS_NAME]) + 1;
>> +	if (attrs[DEVLINK_ATTR_DEV_NAME])
>> +		data_size += nla_len(attrs[DEVLINK_ATTR_DEV_NAME]) + 1;
>> +
>> +	flt = kzalloc(sizeof(*flt) + data_size, GFP_KERNEL);
>
>instead of arithmetic here, you could use struct_size()

That is used for flex array, yet I have no flex array here.

>
>> +	if (!flt)
>> +		return -ENOMEM;
>> +
>> +	pos = (char *) flt->data;
>> +	if (attrs[DEVLINK_ATTR_BUS_NAME]) {
>> +		data_offset += nla_strscpy(pos,
>> +					   attrs[DEVLINK_ATTR_BUS_NAME],
>> +					   data_size) + 1;
>> +		flt->bus_name = pos;
>> +		pos += data_offset;
>> +	}
>> +	if (attrs[DEVLINK_ATTR_DEV_NAME]) {
>> +		nla_strscpy(pos, attrs[DEVLINK_ATTR_DEV_NAME],
>> +			    data_size - data_offset);
>> +		flt->dev_name = pos;
>> +	}
>> +
>> +	/* Don't attach empty filter. */
>> +	if (!flt->bus_name && !flt->dev_name) {
>> +		kfree(flt);
>> +		flt = NULL;
>> +	}
>> +
>

[...]