Re: [PATCH net 1/1] i40e: fix PTP pins verification

[Tony Nguyen <anthony.l.nguyen@intel.com>]

On 4/27/2023 3:24 AM, Paolo Abeni wrote:
> On Wed, 2023-04-26 at 06:52 -0700, Richard Cochran wrote:
>> On Wed, Apr 26, 2023 at 10:18:12AM +0300, Leon Romanovsky wrote:
>>> On Tue, Apr 25, 2023 at 10:04:06AM -0700, Tony Nguyen wrote:
>>>> From: Andrii Staikov <andrii.staikov@intel.com>
>>>>
>>>> Fix PTP pins verification not to contain tainted arguments. As a new PTP
>>>> pins configuration is provided by a user, it may contain tainted
>>>> arguments that are out of bounds for the list of possible values that can
>>>> lead to a potential security threat. Change pin's state name from 'invalid'
>>>> to 'empty' for more clarification.
>>>
>>> And why isn't this handled in upper layer which responsible to get
>>> user input?
>>
>> It is.
>>
>> long ptp_ioctl(struct posix_clock *pc, unsigned int cmd, unsigned long arg)
>> {
>> 	...
>>
>> 	switch (cmd) {
>>
>> 	case PTP_PIN_SETFUNC:
>> 	case PTP_PIN_SETFUNC2:
>> 		if (copy_from_user(&pd, (void __user *)arg, sizeof(pd))) {
>> 			err = -EFAULT;
>> 			break;
>> 		}
>> 		...
>>
>> 		pin_index = pd.index;
>> 		if (pin_index >= ops->n_pins) {
>> 			err = -EINVAL;
>> 			break;
>> 		}
>>
>> 		...
>> 	}
>> 	...
>> }
> 
> Given the above, I don't see why/how this patch is necessary? @Tony,
> @Andrii: could you please give a better/longer description of the issue
> addressed here?

I'm not sure about the issue details; Andrii please chime in.

Thanks,
Tony