From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753065Ab1KYPf6 (ORCPT ); Fri, 25 Nov 2011 10:35:58 -0500 Received: from mail-bw0-f46.google.com ([209.85.214.46]:45002 "EHLO mail-bw0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751173Ab1KYPf5 (ORCPT ); Fri, 25 Nov 2011 10:35:57 -0500 Date: Fri, 25 Nov 2011 15:35:53 +0000 From: Jamie Iles To: Jamie Iles , Rob Herring Cc: Rob Herring , linux-kernel@vger.kernel.org, Thomas Gleixner , Grant Likely , Mark Brown Subject: Re: [PATCH] irq: fix possible null-pointer deref irq_domain_to_irq Message-ID: <20111125153553.GB8866@totoro> References: <1320922383-15312-1-git-send-email-jamie@jamieiles.com> <20111110111446.GB16018@totoro> <4EBBD39C.9000400@gmail.com> <20111123122308.GA7382@totoro> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20111123122308.GA7382@totoro> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Rob, On Wed, Nov 23, 2011 at 12:23:08PM +0000, Jamie Iles wrote: > On Thu, Nov 10, 2011 at 07:37:32AM -0600, Rob Herring wrote: > > On 11/10/2011 05:14 AM, Jamie Iles wrote: > > > On Thu, Nov 10, 2011 at 10:53:03AM +0000, Jamie Iles wrote: > > >> It is optional for an irqdomain to have a to_irq() method, and for > > >> simple domains they often don't require any operations at all - just > > >> hwirq to Linux irq translation. Check we have valid ops before > > >> dereferencing them. > > >> > > >> Patch originally by Rob Herring. > > >> > > >> Suggested-by: Rob Herring > > > > > > Naturally git send-email doesn't know how to convert this into a CC, so > > > Rob is now CC'd! > > > > > > Jamie > > > > > >> Cc: Thomas Gleixner > > >> Cc: Grant Likely > > >> Signed-off-by: Jamie Iles > > >> --- > > >> > > >> Rob, I can't see that you've already posted this but I didn't want to > > >> hold Marc's GIC patches up. > > > > Thanks. I didn't get around to it yesterday. > > > > Acked-by: Rob Herring > > I've just noticed in kernel/irq/irqdomain.c, that the kerneldoc for > irq_domain_add() says that a valid ops structure is required, so perhaps > this fix isn't right and we should just have an empty ops structure for > simple controllers... 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, +}; +EXPORT_SYMBOL_GPL(irq_domain_simple_ops);