From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755330AbaD1Bco (ORCPT ); Sun, 27 Apr 2014 21:32:44 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:42927 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752577AbaD1B3V (ORCPT ); Sun, 27 Apr 2014 21:29:21 -0400 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Krzysztof Kozlowski" , "Lee Jones" Date: Mon, 28 Apr 2014 02:11:22 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.2 53/94] mfd: max8998: Fix possible NULL pointer dereference on i2c_new_dummy error In-Reply-To: X-SA-Exim-Connect-IP: 192.168.4.249 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.2.58-rc1 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: Ben Hutchings --- drivers/mfd/max8998.c | 4 ++++ 1 file changed, 4 insertions(+) --- a/drivers/mfd/max8998.c +++ b/drivers/mfd/max8998.c @@ -152,6 +152,10 @@ static int max8998_i2c_probe(struct 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);