Re: [PATCH] net: stmmac: add sanity check to device_property_read_u32_array call

From: Colin Ian King
Date: Tue Jul 02 2019 - 02:48:23 EST


On 01/07/2019 23:43, Martin Blumenstingl wrote:
> On Fri, Jun 28, 2019 at 6:05 PM Martin Blumenstingl
> <martin.blumenstingl@xxxxxxxxxxxxxx> wrote:
>>
>> Hi Colin,
>>
>> On Fri, Jun 28, 2019 at 10:32 AM Colin Ian King
>> <colin.king@xxxxxxxxxxxxx> wrote:
>>>
>>> On 28/06/2019 05:15, Martin Blumenstingl wrote:
>>>> On Tue, Jun 25, 2019 at 9:58 AM Colin Ian King <colin.king@xxxxxxxxxxxxx> wrote:
>>>>>
>>>>> On 25/06/2019 05:44, Martin Blumenstingl wrote:
>>>>>> Hi Colin,
>>>>>>
>>>>>> On Thu, Jun 20, 2019 at 3:34 AM Martin Blumenstingl
>>>>>> <martin.blumenstingl@xxxxxxxxxxxxxx> wrote:
>>>>>>>
>>>>>>> Hi Colin,
>>>>>>>
>>>>>>> On Wed, Jun 19, 2019 at 8:55 AM Colin Ian King <colin.king@xxxxxxxxxxxxx> wrote:
>>>>>>>>
>>>>>>>> On 19/06/2019 06:13, Martin Blumenstingl wrote:
>>>>>>>>> Hi Colin,
>>>>>>>>>
>>>>>>>>>> Currently the call to device_property_read_u32_array is not error checked
>>>>>>>>>> leading to potential garbage values in the delays array that are then used
>>>>>>>>>> in msleep delays. Add a sanity check to the property fetching.
>>>>>>>>>>
>>>>>>>>>> Addresses-Coverity: ("Uninitialized scalar variable")
>>>>>>>>>> Signed-off-by: Colin Ian King <colin.king@xxxxxxxxxxxxx>
>>>>>>>>> I have also sent a patch [0] to fix initialize the array.
>>>>>>>>> can you please look at my patch so we can work out which one to use?
>>>>>>>>>
>>>>>>>>> my concern is that the "snps,reset-delays-us" property is optional,
>>>>>>>>> the current dt-bindings documentation states that it's a required
>>>>>>>>> property. in reality it isn't, there are boards (two examples are
>>>>>>>>> mentioned in my patch: [0]) without it.
>>>>>>>>>
>>>>>>>>> so I believe that the resulting behavior has to be:
>>>>>>>>> 1. don't delay if this property is missing (instead of delaying for
>>>>>>>>> <garbage value> ms)
>>>>>>>>> 2. don't error out if this property is missing
>>>>>>>>>
>>>>>>>>> your patch covers #1, can you please check whether #2 is also covered?
>>>>>>>>> I tested case #2 when submitting my patch and it worked fine (even
>>>>>>>>> though I could not reproduce the garbage values which are being read
>>>>>>>>> on some boards)
>>>>>> in the meantime I have tested your patch.
>>>>>> when I don't set the "snps,reset-delays-us" property then I get the
>>>>>> following error:
>>>>>> invalid property snps,reset-delays-us
>>>>>>
>>>>>> my patch has landed in the meantime: [0]
>>>>>> how should we proceed with your patch?
>>>
>>> Your fix is good, so I think we should just drop/forget about my fix.
>> thank you for looking at the situation
>>
>> as far I understand the -net/-net-next tree all commits are immutable
>> so if we want to remove your patch we need to send a revert
>> do you want me to do that (I can do it on Monday) or will you take care of that?
> I just sent the patch: [0]

Thank you, much appreciated.
>
>
> [0] https://patchwork.ozlabs.org/patch/1125686/
>