Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754813AbaFKKIQ (ORCPT ); Wed, 11 Jun 2014 06:08:16 -0400 Received: from aserp1040.oracle.com ([141.146.126.69]:41422 "EHLO aserp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751310AbaFKKIO (ORCPT ); Wed, 11 Jun 2014 06:08:14 -0400 Date: Wed, 11 Jun 2014 13:07:52 +0300 From: Dan Carpenter To: Pawel Moll Cc: Arnd Bergmann , Lee Jones , Greg Kroah-Hartman , Samuel Ortiz , "linux-kernel@vger.kernel.org" , "kernel-janitors@vger.kernel.org" Subject: Re: [patch] mfd: vexpress: use after free in vexpress_syscfg_regmap_init() Message-ID: <20140611100752.GR5500@mwanda> References: <20140611060725.GC7569@mwanda> <1402478542.3523.9.camel@hornet> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1402478542.3523.9.camel@hornet> User-Agent: Mutt/1.5.21 (2010-09-15) X-Source-IP: ucsinet22.oracle.com [156.151.31.94] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jun 11, 2014 at 10:22:22AM +0100, Pawel Moll wrote: > On Wed, 2014-06-11 at 07:07 +0100, Dan Carpenter wrote: > > We should return NULL if regmap_init() fails instead of continuing. > > > > Signed-off-by: Dan Carpenter > > > > diff --git a/drivers/misc/vexpress-syscfg.c b/drivers/misc/vexpress-syscfg.c > > index 73068e5..2c0ddb2 100644 > > --- a/drivers/misc/vexpress-syscfg.c > > +++ b/drivers/misc/vexpress-syscfg.c > > @@ -231,10 +231,12 @@ static struct regmap *vexpress_syscfg_regmap_init(struct device *dev, > > func->regmap = regmap_init(dev, NULL, func, > > &vexpress_syscfg_regmap_config); > > > > - if (IS_ERR(func->regmap)) > > + if (IS_ERR(func->regmap)) { > > kfree(func); > > - else > > - list_add(&func->list, &syscfg->funcs); > > + return NULL; > > + } > > + > > + list_add(&func->list, &syscfg->funcs); > > > > return func->regmap; > > } > > Not really, no. What made you think so? > > vexpress_config_bridge_ops.regmap_init should return an ERR_PTR in case > of troubles, not a NULL. See devm_regmap_init_vexpress_config() in > drivers/bus/vexpress-config.c: > > regmap = bridge->ops->regmap_init(dev, bridge->context); > if (IS_ERR(regmap)) { Ah... That was sloppy of me. There is a similar bug earlier and I'll fix that as well. regards, dan carpenter -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/