Re: [PATCH] pinctrl: bcm2835: Fix a few error paths

[Florian Fainelli]

On 1/28/2022 6:35 AM, Andy Shevchenko wrote:
> On Thu, Jan 27, 2022 at 01:50:31PM -0800, Florian Fainelli wrote:
> > After commit 266423e60ea1 ("pinctrl: bcm2835: Change init order for gpio
> > hogs") a few error paths would not unwind properly the registration of
> > gpio ranges. Correct that by assigning a single error label and goto it
> > whenever we encounter a fatal error.
>
> >   1 file changed, 15 insertions(+), 8 deletions(-)
>
> While this seems legit per se, my eyes caught this:
>
>
> >   	if (!girq->parents) {
> > -		pinctrl_remove_gpio_range(pc->pctl_dev, &pc->gpio_range);
> > -		return -ENOMEM;
> > +		err = -ENOMEM;
> > +		goto out_remove;
>
> Non-devm....
>
> >   	}
> >   
> >   	if (is_7211) {
> >   		pc->wake_irq = devm_kcalloc(dev, BCM2835_NUM_IRQS,
> >   					    sizeof(*pc->wake_irq),
> >   					    GFP_KERNEL);
>
> ...followed by devm.
>
> It means more ordering bugs in the ->remove() and error path are lurking
> around. Can you double check and be sure that we do not have a case where
> non-devm registration code followed by devm?

It seems to me like we are fine with the patch as is, because:

- girq->parents is allocated with devm
- pc->wake_irq is allocated with devm
- name is allocated with devm

and those are the only variables being allocated for which we also 
process an error handling path.
--
Florian