From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754653AbaD1Bb2 (ORCPT ); Sun, 27 Apr 2014 21:31:28 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:42934 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752581AbaD1B3V (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, "Lee Jones" , "Krzysztof Kozlowski" Date: Mon, 28 Apr 2014 02:11:22 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.2 55/94] mfd: 88pm860x: 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 159ce52a6b777fc82fa0b51c7440e25f9e4c6feb upstream. During probe the driver allocates dummy I2C device for companion chip 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 regmap_init_i2c(). If i2c_new_dummy() fails for companion device, fail also the probe for main MFD driver. Signed-off-by: Krzysztof Kozlowski Signed-off-by: Lee Jones [bwh: Backported to 3.2: - Adjust filename, context - Add kfree() before return, as driver is not using managed allocations] Signed-off-by: Ben Hutchings --- drivers/mfd/88pm860x-i2c.c | 5 +++++ 1 file changed, 5 insertions(+) --- a/drivers/mfd/88pm860x-i2c.c +++ b/drivers/mfd/88pm860x-i2c.c @@ -290,6 +290,12 @@ static int __devinit pm860x_probe(struct chip->companion_addr = pdata->companion_addr; chip->companion = i2c_new_dummy(chip->client->adapter, chip->companion_addr); + if (!chip->companion) { + dev_err(&client->dev, + "Failed to allocate I2C companion device\n"); + kfree(chip); + return -ENODEV; + } i2c_set_clientdata(chip->companion, chip); }