Re: [patch iproute2-next v3 3/6] devlink: extend pr_out_nested_handle() to print object

[Jiri Pirko <jiri@resnulli.us>]

Thu, Oct 26, 2023 at 07:03:30PM CEST, dsahern@gmail.com wrote:
>On 10/24/23 4:04 AM, Jiri Pirko wrote:
>> @@ -2861,6 +2842,38 @@ static void pr_out_selftests_handle_end(struct dl *dl)
>>  		__pr_out_newline();
>>  }
>>  
>> +static void __pr_out_nested_handle(struct dl *dl, struct nlattr *nla_nested_dl,
>> +				   bool is_object)
>> +{
>> +	struct nlattr *tb[DEVLINK_ATTR_MAX + 1] = {};
>> +	int err;
>> +
>> +	err = mnl_attr_parse_nested(nla_nested_dl, attr_cb, tb);
>> +	if (err != MNL_CB_OK)
>> +		return;
>> +
>> +	if (!tb[DEVLINK_ATTR_BUS_NAME] ||
>> +	    !tb[DEVLINK_ATTR_DEV_NAME])
>> +		return;
>> +
>> +	if (!is_object) {
>> +		char buf[64];
>> +
>> +		sprintf(buf, "%s/%s", mnl_attr_get_str(tb[DEVLINK_ATTR_BUS_NAME]),
>> +			mnl_attr_get_str(tb[DEVLINK_ATTR_DEV_NAME]));
>
>buf[64] - 1 for null terminator - 16 for IFNAMSIZ leaves 47. I do not

IFNAMSIZ is irrelevant here.


>see limits on bus name length, so how can you guarantee it is always <
>47 characters?
>
>Make this snprintf, check the return and make sure buf is null terminated.

I will fix it in separate patch, as this is just copied here.


>
>> +		print_string(PRINT_ANY, "nested_devlink", " nested_devlink %s", buf);
>> +		return;
>> +	}
>> +
>> +	__pr_out_handle_start(dl, tb, false, false);
>> +	pr_out_handle_end(dl);
>> +}
>> +
>> +static void pr_out_nested_handle(struct nlattr *nla_nested_dl)
>> +{
>> +	__pr_out_nested_handle(NULL, nla_nested_dl, false);
>> +}
>> +
>>  static bool cmp_arr_last_port_handle(struct dl *dl, const char *bus_name,
>>  				     const char *dev_name, uint32_t port_index)
>>  {
>