From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754796AbaEDPmi (ORCPT ); Sun, 4 May 2014 11:42:38 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:36516 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754613AbaEDPmX (ORCPT ); Sun, 4 May 2014 11:42:23 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Krzysztof Kozlowski , Lee Jones Subject: [PATCH 3.10 25/86] mfd: max77686: Fix possible NULL pointer dereference on i2c_new_dummy error Date: Sun, 4 May 2014 11:41:00 -0400 Message-Id: <20140504154143.811898229@linuxfoundation.org> X-Mailer: git-send-email 1.9.0 In-Reply-To: <20140504154140.444932005@linuxfoundation.org> References: <20140504154140.444932005@linuxfoundation.org> User-Agent: quilt/0.60-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.10-stable review patch. If anyone has any objections, please let me know. ------------------ From: Krzysztof Kozlowski commit b9e183a1d495cd65412abe0f9df19b151716bfe7 upstream. During probe the driver allocates dummy I2C device for RTC with i2c_new_dummy() but it does not check the return value of this call. 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 device, fail also the probe for main MFD driver. Signed-off-by: Krzysztof Kozlowski Signed-off-by: Lee Jones Signed-off-by: Greg Kroah-Hartman --- drivers/mfd/max77686.c | 4 ++++ 1 file changed, 4 insertions(+) --- a/drivers/mfd/max77686.c +++ b/drivers/mfd/max77686.c @@ -121,6 +121,10 @@ static int max77686_i2c_probe(struct i2c dev_info(max77686->dev, "device found\n"); max77686->rtc = i2c_new_dummy(i2c->adapter, I2C_ADDR_RTC); + if (!max77686->rtc) { + dev_err(max77686->dev, "Failed to allocate I2C device for RTC\n"); + return -ENODEV; + } i2c_set_clientdata(max77686->rtc, max77686); max77686_irq_init(max77686);