From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752619AbaBKMW6 (ORCPT ); Tue, 11 Feb 2014 07:22:58 -0500 Received: from mail-we0-f170.google.com ([74.125.82.170]:45734 "EHLO mail-we0-f170.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751935AbaBKMW4 (ORCPT ); Tue, 11 Feb 2014 07:22:56 -0500 Date: Tue, 11 Feb 2014 12:22:49 +0000 From: Lee Jones To: Krzysztof Kozlowski Cc: Sangbeom Kim , Samuel Ortiz , linux-kernel@vger.kernel.org, linux-samsung-soc@vger.kernel.org, Kyungmin Park , Marek Szyprowski , Bartlomiej Zolnierkiewicz , stable@vger.kernel.org Subject: Re: [PATCH 4/7] mfd: max77693: Fix possible NULL pointer dereference on i2c_new_dummy error Message-ID: <20140211122249.GS32042@lee--X1> References: <1392113015-11180-1-git-send-email-k.kozlowski@samsung.com> <1392113015-11180-4-git-send-email-k.kozlowski@samsung.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <1392113015-11180-4-git-send-email-k.kozlowski@samsung.com> 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 On Tue, 11 Feb 2014, Krzysztof Kozlowski wrote: > During probe the driver allocates dummy I2C devices for MUIC and haptic > with i2c_new_dummy() but it does not check the return value of this > calls. > > In case of error (i2c_new_device(): memory allocation failure or I2C > address cannot be used) this function returns NULL which is later used > by devm_regmap_init_i2c() and i2c_unregister_device(). > > If i2c_new_dummy() fails for MUIC or haptic devices, fail also the probe > for main MFD driver. > > Signed-off-by: Krzysztof Kozlowski > Cc: stable@vger.kernel.org > --- > drivers/mfd/max77693.c | 12 +++++++++++- > 1 file changed, 11 insertions(+), 1 deletion(-) > > diff --git a/drivers/mfd/max77693.c b/drivers/mfd/max77693.c > index e0859987ab6b..c5535f018466 100644 > --- a/drivers/mfd/max77693.c > +++ b/drivers/mfd/max77693.c > @@ -148,9 +148,18 @@ static int max77693_i2c_probe(struct i2c_client *i2c, > dev_info(max77693->dev, "device ID: 0x%x\n", reg_data); > > max77693->muic = i2c_new_dummy(i2c->adapter, I2C_ADDR_MUIC); > + if (!max77693->muic) { > + dev_err(max77693->dev, "Failed to allocate I2C device for MUIC\n"); > + return -ENODEV; > + } > i2c_set_clientdata(max77693->muic, max77693); > > max77693->haptic = i2c_new_dummy(i2c->adapter, I2C_ADDR_HAPTIC); > + if (!max77693->haptic) { > + dev_err(max77693->dev, "Failed to allocate I2C device for Haptic\n"); > + ret = -ENODEV; > + goto err_i2c_haptic; > + } > i2c_set_clientdata(max77693->haptic, max77693); > > /* > @@ -184,8 +193,9 @@ err_mfd: > max77693_irq_exit(max77693); > err_irq: > err_regmap_muic: > - i2c_unregister_device(max77693->muic); > i2c_unregister_device(max77693->haptic); > +err_i2c_haptic: > + i2c_unregister_device(max77693->muic); > return ret; > } > Applied, thanks. -- Lee Jones Linaro STMicroelectronics Landing Team Lead Linaro.org │ Open source software for ARM SoCs Follow Linaro: Facebook | Twitter | Blog