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Date:   Mon, 4 Dec 2023 07:38:13 +0100
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Subject: Re: [PATCH] egalax_ts_serial: Fix potential buffer overflow
To:     Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc:     linux-kernel@vger.kernel.org, oe-kbuild-all@lists.linux.dev,
        zboszormenyi@sicom.com, kernel test robot <lkp@intel.com>
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2023. 12. 03. 19:35 keltezéssel, Dmitry Torokhov írta:
> Hi Zoltán,
>
> On Sun, Dec 03, 2023 at 10:06:00AM +0100, Zoltán Böszörményi wrote:
>> @@ -42,7 +42,7 @@ struct egalax {
>>   	struct serio *serio;
>>   	int idx;
>>   	u8 data[EGALAX_FORMAT_MAX_LENGTH];
>> -	char phys[32];
>> +	char phys[NAME_MAX];
> This simply wastes 200+ bytes for no good reason. It is perfectly fine
> to truncate phys string (which does not happen in practice).

Okay, I modified the phys[] array to just be 40 bytes.
That's not that wasteful and still avoids the warning.

I noticed that other TS drivers emit the same warning.

>
> If you feel strongly about it then maybe use devm_kasprintf() to
> allocate the needed buffer.
>
> Thanks.
>