Re: [PATCH] irq: fix possible null-pointer deref irq_domain_to_irq

From: Jamie Iles
Date: Sun Nov 27 2011 - 10:32:36 EST


Hi Rob,

On Sun, Nov 27, 2011 at 09:11:01AM -0600, Rob Herring wrote:
> On 11/25/2011 09:35 AM, Jamie Iles wrote:
> > I wonder if this might make more sense instead. I'll post a proper
> > patch if you think so.
> >
> > Regards,
> >
> > Jamie
> >
> > diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c
> > index 200ce83..92c3484 100644
> > --- a/kernel/irq/irqdomain.c
> > +++ b/kernel/irq/irqdomain.c
> > @@ -143,11 +143,6 @@ int irq_domain_simple_dt_translate(struct irq_domain *d,
> > return 0;
> > }
> >
> > -struct irq_domain_ops irq_domain_simple_ops = {
> > - .dt_translate = irq_domain_simple_dt_translate,
> > -};
> > -EXPORT_SYMBOL_GPL(irq_domain_simple_ops);
> > -
> > /**
> > * irq_domain_create_simple() - Set up a 'simple' translation range
> > */
> > @@ -181,4 +176,11 @@ void irq_domain_generate_simple(const struct of_device_id *match,
> > pr_info("no node found\n");
> > }
> > EXPORT_SYMBOL_GPL(irq_domain_generate_simple);
> > +#else /* CONFIG_OF_IRQ */
> > +#define irq_domain_simple_dt_translate NULL
> > #endif /* CONFIG_OF_IRQ */
> > +
> > +struct irq_domain_ops irq_domain_simple_ops = {
> > + .dt_translate = irq_domain_simple_dt_translate,
>
> .dt_translate is surrounded by CONFIG_OF, so it will break on !CONFIG_OF.

Ahh, good spot!

> > +};
> > +EXPORT_SYMBOL_GPL(irq_domain_simple_ops);
>
> The extern declaration in irqdomain.h is surrounded by CONFIG_OF_IRQ, so
> it needs to be moved out of that as well.
>
> On Sparc, CONFIG_OF is true, but CONFIG_OF_IRQ is false. So that
> combination needs to be handled as well.

OK, I'm travelling for a couple of days now, but I'll respin something
when I'm back. I guess it's a case of always exporting the simple ops
when CONFIG_IRQDOMAIN=y, and only setting the .dt_translate when
CONFIG_OF_IRQ=y though.

Jamie
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/