From patchwork Tue Apr 22 20:13:39 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kamal Mostafa X-Patchwork-Id: 341587 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from huckleberry.canonical.com (huckleberry.canonical.com [91.189.94.19]) by ozlabs.org (Postfix) with ESMTP id 21D75140083; Wed, 23 Apr 2014 06:28:08 +1000 (EST) Received: from localhost ([127.0.0.1] helo=huckleberry.canonical.com) by huckleberry.canonical.com with esmtp (Exim 4.76) (envelope-from ) id 1WchIS-0005B7-I6; Tue, 22 Apr 2014 20:28:04 +0000 Received: from youngberry.canonical.com ([91.189.89.112]) by huckleberry.canonical.com with esmtp (Exim 4.76) (envelope-from ) id 1WchFH-0003LP-Ik for kernel-team@lists.ubuntu.com; Tue, 22 Apr 2014 20:24:47 +0000 Received: from c-67-160-228-185.hsd1.ca.comcast.net ([67.160.228.185] helo=fourier) by youngberry.canonical.com with esmtpsa (TLS1.0:DHE_RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1Wch5x-00058G-Ed; Tue, 22 Apr 2014 20:15:09 +0000 Received: from kamal by fourier with local (Exim 4.82) (envelope-from ) id 1Wch5v-0003TQ-Go; Tue, 22 Apr 2014 13:15:07 -0700 From: Kamal Mostafa To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Subject: [PATCH 3.8 081/133] mfd: max8998: Fix possible NULL pointer dereference on i2c_new_dummy error Date: Tue, 22 Apr 2014 13:13:39 -0700 Message-Id: <1398197671-12786-82-git-send-email-kamal@canonical.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1398197671-12786-1-git-send-email-kamal@canonical.com> References: <1398197671-12786-1-git-send-email-kamal@canonical.com> X-Extended-Stable: 3.8 Cc: Krzysztof Kozlowski , Lee Jones , Kamal Mostafa X-BeenThere: kernel-team@lists.ubuntu.com X-Mailman-Version: 2.1.14 Precedence: list List-Id: Kernel team discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: kernel-team-bounces@lists.ubuntu.com Sender: kernel-team-bounces@lists.ubuntu.com 3.8.13.22 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Krzysztof Kozlowski commit ed26f87b9f71693a1d1ee85f5e6209601505080f 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: Kamal Mostafa --- drivers/mfd/max8998.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/mfd/max8998.c b/drivers/mfd/max8998.c index d7218cc..8381a76 100644 --- a/drivers/mfd/max8998.c +++ b/drivers/mfd/max8998.c @@ -152,6 +152,10 @@ static int max8998_i2c_probe(struct i2c_client *i2c, mutex_init(&max8998->iolock); max8998->rtc = i2c_new_dummy(i2c->adapter, RTC_I2C_ADDR); + if (!max8998->rtc) { + dev_err(&i2c->dev, "Failed to allocate I2C device for RTC\n"); + return -ENODEV; + } i2c_set_clientdata(max8998->rtc, max8998); max8998_irq_init(max8998);