Re: [PATCH] atmel: using strlcpy() to avoid possible buffer overflows

[YueHaibing]

On 2018/6/30 5:51, Andy Shevchenko wrote:
> On Sat, Jun 30, 2018 at 12:47 AM, Andy Shevchenko
> <andy.shevchenko@xxxxxxxxx> wrote:
>> On Fri, Jun 29, 2018 at 5:51 AM, YueHaibing <yuehaibing@xxxxxxxxxx> wrote:
>>> 'firmware' is a module param which may been longer than firmware_id,
>>> so using strlcpy() to guard against overflows
>>
>> strncat() is against overflow, this does a bit more.
>>
>>>         priv->firmware_id[0] = '\0';
>> ...
>>>         if (firmware) /* module parameter */
>>> -               strcpy(priv->firmware_id, firmware);
>>> +               strlcpy(priv->firmware_id, firmware, sizeof(priv->firmware_id));
>>
>> In either case the above '\0' is not needed.
>> But it looks like the intention was to use strncat() / strlcat().
> 
> Ah, this is under condition, yes. If no parameter supplied, this needs
> to be clean, but
> priv is allocated with zeroed memory
> https://elixir.bootlin.com/linux/latest/source/net/core/dev.c#L8369

so just remove this line:
	 priv->firmware_id[0] = '\0';

and using strlcpy while 'firmware' NOT null is enough.

Will send v2.

>