Re: [PATCH 3/3] input: misc: pm8941-pwrkey: avoid potential null pointer dereference

From: Anjelique Melendez
Date: Thu Jan 20 2022 - 19:15:55 EST



On 1/20/2022 2:18 PM, Trilok Soni wrote:
> On 1/20/2022 12:41 PM, Anjelique Melendez wrote:
>> From: David Collins <collinsd@xxxxxxxxxxxxxx>
>>
>> Add a null check for the pwrkey->data pointer after it is assigned
>> in pm8941_pwrkey_probe().  This avoids a potential null pointer
>> dereference when pwrkey->data->has_pon_pbs is accessed later in
>> the probe function.
>>
>> Change-Id: I589c4851e544d79a1863fd110b32a0b45ac03caf
>> Signed-off-by: David Collins <collinsd@xxxxxxxxxxxxxx>
>> Signed-off-by: Anjelique Melendez <quic_amelende@xxxxxxxxxxx>
>> ---
>>   drivers/input/misc/pm8941-pwrkey.c | 4 ++++
>>   1 file changed, 4 insertions(+)
>>
>> diff --git a/drivers/input/misc/pm8941-pwrkey.c b/drivers/input/misc/pm8941-pwrkey.c
>> index 0ce00736e695..ac08ed025802 100644
>> --- a/drivers/input/misc/pm8941-pwrkey.c
>> +++ b/drivers/input/misc/pm8941-pwrkey.c
>> @@ -263,6 +263,10 @@ static int pm8941_pwrkey_probe(struct platform_device *pdev)
>>         pwrkey->dev = &pdev->dev;
>>       pwrkey->data = of_device_get_match_data(&pdev->dev);
>> +    if (!pwrkey->data) {
>> +        dev_err(&pdev->dev, "match data not found\n");
>> +        return -ENODEV;
>> +    }
>>  
>
> I don't understand why this patch is 3rd in the series. Isn't it independent from the debounce time? If not, then why it is not fixed as part of the patch which adds this debounce time support?
>
> ---Trilok Soni
You are correct that this patch is independent from debounce time. In the following version I will move this patch up to be the first patch!