[dpdk-dev] Questions about API with no parameter check

[Min Hu (Connor)]

Thanks all,
Well, Most people who replied support input verification for APIs.
As the APIs are in control path APIs, so checking all input is OK.

This is a large project because there are so many APIs and libs in DPDK.
I will send a set of patches to fix that.

Thomas, Ferruh, and others, any opinions ?

Thanks.


在 2021/4/8 0:26, Burakov, Anatoly 写道:
> On 07-Apr-21 5:10 PM, Ferruh Yigit wrote:
>> On 4/7/2021 4:25 PM, Hemant Agrawal wrote:
>>>
>>> On 4/7/2021 8:10 PM, Ajit Khaparde wrote:
>>>> On Wed, Apr 7, 2021 at 6:20 AM Jerin Jacob <jerinjacobk at gmail.com> 
>>>> wrote:
>>>>> On Wed, Apr 7, 2021 at 5:23 PM Ananyev, Konstantin
>>>>> <konstantin.ananyev at intel.com> wrote:
>>>>>>
>>>>>>
>>>>>>> 07/04/2021 13:28, Min Hu (Connor):
>>>>>>>> Hi, all,
>>>>>>>>      Many APIs in DPDK does not check if the pointer parameter is
>>>>>>>> NULL or not. For example, in 'rte_ethdev.c':
>>>>>>>> int
>>>>>>>> rte_eth_rx_queue_setup(uint16_t port_id, uint16_t rx_queue_id,
>>>>>>>>                     uint16_t nb_rx_desc, unsigned int socket_id,
>>>>>>>>                     const struct rte_eth_rxconf *rx_conf,
>>>>>>>>                     struct rte_mempool *mp)
>>>>>>>>
>>>>>>>> int
>>>>>>>> rte_eth_link_get(uint16_t port_id, struct rte_eth_link *eth_link)
>>>>>>>>
>>>>>>>> int
>>>>>>>> rte_eth_stats_get(uint16_t port_id, struct rte_eth_stats *stats)
>>>>>>>>
>>>>>>>> int
>>>>>>>> rte_eth_dev_info_get(uint16_t port_id, struct rte_eth_dev_info 
>>>>>>>> *dev_info)
>>>>>>>>
>>>>>>>> As these APIs could be used by any APPs, if the APP give NULL as
>>>>>>>> the pointer parameter, segmetation default will occur.
>>>>>>>>
>>>>>>>> So, my question is, should we add check in the API? like that,
>>>>>>>> int rte_eth_stats_get(uint16_t port_id, struct rte_eth_stats 
>>>>>>>> *stats)
>>>>>>>> {
>>>>>>>>      if (stats == NULL)
>>>>>>>>              return -EINVAL;
>>>>>>>>      ...
>>>>>>>> }
>>>>>>>>
>>>>>>>> Or, that is redundant, the parameter correctness should be 
>>>>>>>> guaranteed by
>>>>>>>> the APP?
>>>>>>>>
>>>>>>>> What's your opinion? Hope for your reply.
>>>>>>> I remember it has been discussed in the past (many years ago),
>>>>>>> and the opinion was to not clutter the code for something that
>>>>>>> is a basic fault from the app.
>>>>>>>
>>>>>>> I don't have a strong opinion.
>>>>>>> What is your opinion? Others?
>>>>>> As I can see these are control path functions.
>>>>>> So some extra formal parameters check wouldn't hurt.
>>>>>> +1 from me to add them.
>>>>> +1 to add more sanity checks in control path APIs
>>>> +1
>>>> But are we going to check all parameters?
>>>
>>> +1
>>>
>>> It may be better to limit the number of checks.
>>>
>>
>> +1 to verify input for APIs.
>>
>> Why not do all, what is the downside of checking all input for control 
>> path APIs?
>>
> 
> +1
> 
> Don't have anything useful to add that hasn't already been said, but 
> seems like a nice +1-train going on here, so i thought i'd hop on board :D
>