From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Date: Tue, 11 Feb 2014 12:23:14 +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 5/7] mfd: max8925: Fix possible NULL pointer dereference on i2c_new_dummy error Message-ID: <20140211122314.GT32042@lee--X1> References: <1392113015-11180-1-git-send-email-k.kozlowski@samsung.com> <1392113015-11180-5-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: <1392113015-11180-5-git-send-email-k.kozlowski@samsung.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: On Tue, 11 Feb 2014, Krzysztof Kozlowski wrote: > During probe the driver allocates dummy I2C devices for RTC and ADC > 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 i2c_unregister_device(). > > If i2c_new_dummy() fails for RTC or ADC devices, fail also the probe > for main MFD driver. > > Signed-off-by: Krzysztof Kozlowski > Cc: stable@vger.kernel.org > --- > drivers/mfd/max8925-i2c.c | 9 +++++++++ > 1 file changed, 9 insertions(+) > > diff --git a/drivers/mfd/max8925-i2c.c b/drivers/mfd/max8925-i2c.c > index 176aa26fc787..a83eed5c15ca 100644 > --- a/drivers/mfd/max8925-i2c.c > +++ b/drivers/mfd/max8925-i2c.c > @@ -181,9 +181,18 @@ static int max8925_probe(struct i2c_client *client, > mutex_init(&chip->io_lock); > > chip->rtc = i2c_new_dummy(chip->i2c->adapter, RTC_I2C_ADDR); > + if (!chip->rtc) { > + dev_err(chip->dev, "Failed to allocate I2C device for RTC\n"); > + return -ENODEV; > + } > i2c_set_clientdata(chip->rtc, chip); > > chip->adc = i2c_new_dummy(chip->i2c->adapter, ADC_I2C_ADDR); > + if (!chip->adc) { > + dev_err(chip->dev, "Failed to allocate I2C device for ADC\n"); > + i2c_unregister_device(chip->rtc); > + return -ENODEV; > + } > i2c_set_clientdata(chip->adc, chip); > > device_init_wakeup(&client->dev, 1); Applied, thanks. -- Lee Jones Linaro STMicroelectronics Landing Team Lead Linaro.org │ Open source software for ARM SoCs Follow Linaro: Facebook | Twitter | Blog