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

Jiri Pirko
2023-12-04T16:24:37Z

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;
>> + }
>> +
> …