Re: [PATCH 1/2] extcon: Use BIT() macro for the left-shift operation

[Andy Shevchenko]

On Thu, Mar 30, 2017 at 12:15 PM, Chanwoo Choi <cw00.choi@xxxxxxxxxxx> wrote:
> On 2017ë 03ì 30ì 17:59, Andy Shevchenko wrote:
>> On Thu, Mar 30, 2017 at 11:39 AM, Chanwoo Choi <cw00.choi@xxxxxxxxxxx> wrote:
>>> This patch just uses the BIT() macro to make the code simple.
>>
>>>         for (i = 0; i < edev->max_supported; i++) {
>>>                 count += sprintf(buf + count, "%s=%d\n",
>>>                                 extcon_info[edev->supported_cable[i]].name,
>>> -                                !!(edev->state & (1 << i)));
>>> +                                !!(edev->state & BIT(i)));
>>>         }
>>
>> While change is okay, the above code is fragile. There is a potential
>> buffer overflow.
>
> When extcon device is registered, extcon_dev_register() check a number of
> supported external connectors. The maximum number of supported connectors
> is 32. There is no buffer overflow.

Is there any limit for name? No, there is not (const char *name).
Though for now it is quite unlikely to have the issue.

Feel free to proceed despite my comment.

-- 
With Best Regards,
Andy Shevchenko