From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751769AbaIMGeh (ORCPT ); Sat, 13 Sep 2014 02:34:37 -0400 Received: from mga11.intel.com ([192.55.52.93]:9314 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751477AbaIMGef (ORCPT ); Sat, 13 Sep 2014 02:34:35 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.04,516,1406617200"; d="scan'208";a="598963154" Date: Sat, 13 Sep 2014 09:34:31 +0300 From: Mika Westerberg To: Peter Huewe Cc: Wolfram Sang , linux-i2c@vger.kernel.org, linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] [REGRESSION] i2c-acpi: Fix NULL Pointer dereference Message-ID: <20140913063431.GJ10854@lahna.fi.intel.com> References: <1410548987-3558-1-git-send-email-peterhuewe@gmx.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1410548987-3558-1-git-send-email-peterhuewe@gmx.de> Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Sep 12, 2014 at 09:09:47PM +0200, Peter Huewe wrote: > If adapter->dev.parent == NULL there is a NULL pointer dereference in > acpi_i2c_install_space_handler and acpi_i2c_remove_space_handler. > > This is present since introduction of this code: > 366047515c6e "i2c: rework kernel config I2C_ACPI" or even > da3c6647ee08 "I2C/ACPI: Clean up I2C ACPI code and Add CONFIG_I2C_ACPI" > > The adapter->dev.parent == NULL case is valid for the i2c_stub, > so loading i2c_stub with ACPI_I2C_OPREGION enabled results in an oops. > This is also valid at least for i2c_tiny_usb and i2c_robotfuzz_osif. > > Fix by checking whether it is null before calling ACPI_HANDLE. > > Signed-off-by: Peter Huewe Acked-by: Mika Westerberg