Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S941887AbcJYQmQ (ORCPT ); Tue, 25 Oct 2016 12:42:16 -0400 Received: from mail.kernel.org ([198.145.29.136]:41072 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S941872AbcJYQmM (ORCPT ); Tue, 25 Oct 2016 12:42:12 -0400 From: Kieran Bingham To: Wolfram Sang , Lee Jones , Kieran Bingham Cc: linux-i2c@vger.kernel.org, linux-kernel@vger.kernel.org, Javier Martinez Canillas , sameo@linux.intel.com Subject: [PATCHv6 01/11] i2c: Add pointer dereference protection to i2c_match_id() Date: Tue, 25 Oct 2016 17:41:45 +0100 Message-Id: <1477413715-22894-2-git-send-email-kieran@bingham.xyz> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1477413715-22894-1-git-send-email-kieran@bingham.xyz> References: <1477413715-22894-1-git-send-email-kieran@bingham.xyz> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1884 Lines: 56 From: Lee Jones Here we're providing dereference protection for i2c_match_id(), which saves us having to do it each time it's called. We're also stripping out the (now) needless checks in i2c_device_match(). This patch paves the way for other, similar code trimming. Acked-by: Grant Likely Signed-off-by: Lee Jones Tested-by: Kieran Bingham Reviewed-by: Javier Martinez Canillas Tested-by: Javier Martinez Canillas Signed-off-by: Kieran Bingham --- drivers/i2c/i2c-core.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c index da3a02ef4a31..eec4d4d81bf8 100644 --- a/drivers/i2c/i2c-core.c +++ b/drivers/i2c/i2c-core.c @@ -589,6 +589,9 @@ static inline int acpi_i2c_install_space_handler(struct i2c_adapter *adapter) static const struct i2c_device_id *i2c_match_id(const struct i2c_device_id *id, const struct i2c_client *client) { + if (!(id && client)) + return NULL; + while (id->name[0]) { if (strcmp(client->name, id->name) == 0) return id; @@ -602,8 +605,6 @@ static int i2c_device_match(struct device *dev, struct device_driver *drv) struct i2c_client *client = i2c_verify_client(dev); struct i2c_driver *driver; - if (!client) - return 0; /* Attempt an OF style match */ if (of_driver_match_device(dev, drv)) @@ -614,9 +615,10 @@ static int i2c_device_match(struct device *dev, struct device_driver *drv) return 1; driver = to_i2c_driver(drv); - /* match on an id table if there is one */ - if (driver->id_table) - return i2c_match_id(driver->id_table, client) != NULL; + + /* Finally an I2C match */ + if (i2c_match_id(driver->id_table, client)) + return 1; return 0; } -- 2.7.4