[lvc-project] [PATCH] gpio: davinci: Validate the obtained number of IRQs

[Aleksandr Mishin]

On 21.06.2024 16:59, Bartosz Golaszewski wrote:
> On Tue, Jun 18, 2024 at 4:45 PM Aleksandr Mishin <amishin at t-argos.ru> wrote:
>>
>> Value of pdata->gpio_unbanked is taken from Device Tree. In case of broken
>> DT due to any error this value can be any. Without this value validation
>> there can be out of chips->irqs array boundaries access in
>> davinci_gpio_probe().
>>
>> Validate the obtained nirq value so that it won't exceed the maximum
>> number of IRQs per bank.
>>
>> Found by Linux Verification Center (linuxtesting.org) with SVACE.
>>
> 
> Why not Reported-by: ?

It is an established practice for our project, you can find 700+ applied
patches with similar line:
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/log/?qt=grep&q=linuxtesting.org

> 
> Bart
> 
>> Fixes: eb3744a2dd01 ("gpio: davinci: Do not assume continuous IRQ numbering")
>> Signed-off-by: Aleksandr Mishin <amishin at t-argos.ru>
>> ---
>>   drivers/gpio/gpio-davinci.c | 5 +++++
>>   1 file changed, 5 insertions(+)
>>
>> diff --git a/drivers/gpio/gpio-davinci.c b/drivers/gpio/gpio-davinci.c
>> index bb499e362912..1d0175d6350b 100644
>> --- a/drivers/gpio/gpio-davinci.c
>> +++ b/drivers/gpio/gpio-davinci.c
>> @@ -225,6 +225,11 @@ static int davinci_gpio_probe(struct platform_device *pdev)
>>          else
>>                  nirq = DIV_ROUND_UP(ngpio, 16);
>>
>> +       if (nirq > MAX_INT_PER_BANK) {
>> +               dev_err(dev, "Too many IRQs!\n");
>> +               return -EINVAL;
>> +       }
>> +
>>          chips = devm_kzalloc(dev, sizeof(*chips), GFP_KERNEL);
>>          if (!chips)
>>                  return -ENOMEM;
>> --
>> 2.30.2
>>

-- 
Kind regards
Aleksandr