From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 835B5C4320A for ; Wed, 11 Aug 2021 16:15:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6287760243 for ; Wed, 11 Aug 2021 16:15:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229872AbhHKQQQ (ORCPT ); Wed, 11 Aug 2021 12:16:16 -0400 Received: from mail.ispras.ru ([83.149.199.84]:32874 "EHLO mail.ispras.ru" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229473AbhHKQQO (ORCPT ); Wed, 11 Aug 2021 12:16:14 -0400 Received: from kleverstation.intra.ispras.ru (unknown [10.10.2.220]) by mail.ispras.ru (Postfix) with ESMTPS id 359C2407625F; Wed, 11 Aug 2021 16:15:49 +0000 (UTC) From: Nadezda Lutovinova To: Marc Hulsman Cc: Nadezda Lutovinova , Jean Delvare , Guenter Roeck , Rudolf Marek , linux-hwmon@vger.kernel.org, linux-kernel@vger.kernel.org, ldv-project@linuxtesting.org Subject: [PATCH] hwmon: Correct the error handling in w83793.c, w83791d.c, w83792d.c Date: Wed, 11 Aug 2021 19:15:15 +0300 Message-Id: <20210811161515.17842-2-lutovinova@ispras.ru> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20210811161515.17842-1-lutovinova@ispras.ru> References: <20210811161515.17842-1-lutovinova@ispras.ru> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org If driver read tmp (or val) value sufficient for (tmp & 0x08) && (!(tmp & 0x80)) && ((tmp & 0x7) == ((tmp >> 4) & 0x7)) from device then Null pointer dereference occurs. (It is possible if tmp = 0b0xyz1xyz, where same literals mean same numbers) The patch adds checking if data->lm75[0] is NULL. Found by Linux Driver Verification project (linuxtesting.org). Signed-off-by: Nadezda Lutovinova --- drivers/hwmon/w83791d.c | 2 +- drivers/hwmon/w83792d.c | 2 +- drivers/hwmon/w83793.c | 2 +- 3 files changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/hwmon/w83791d.c b/drivers/hwmon/w83791d.c index 37b25a1474c4..8b30bbfafaa7 100644 --- a/drivers/hwmon/w83791d.c +++ b/drivers/hwmon/w83791d.c @@ -1284,7 +1284,7 @@ static int w83791d_detect_subclients(struct i2c_client *client) data->lm75[0] = devm_i2c_new_dummy_device(&client->dev, adapter, 0x48 + (val & 0x7)); if (!(val & 0x80)) { - if (!IS_ERR(data->lm75[0]) && + if (!IS_ERR_OR_NULL(data->lm75[0]) && ((val & 0x7) == ((val >> 4) & 0x7))) { dev_err(&client->dev, "duplicate addresses 0x%x, " diff --git a/drivers/hwmon/w83792d.c b/drivers/hwmon/w83792d.c index abd5c3a722b9..85ae12d950e1 100644 --- a/drivers/hwmon/w83792d.c +++ b/drivers/hwmon/w83792d.c @@ -950,7 +950,7 @@ w83792d_detect_subclients(struct i2c_client *new_client) data->lm75[0] = devm_i2c_new_dummy_device(&new_client->dev, adapter, 0x48 + (val & 0x7)); if (!(val & 0x80)) { - if (!IS_ERR(data->lm75[0]) && + if (!IS_ERR_OR_NULL(data->lm75[0]) && ((val & 0x7) == ((val >> 4) & 0x7))) { dev_err(&new_client->dev, "duplicate addresses 0x%x, use force_subclient\n", diff --git a/drivers/hwmon/w83793.c b/drivers/hwmon/w83793.c index e7d0484eabe4..9d8c44e2fa6e 100644 --- a/drivers/hwmon/w83793.c +++ b/drivers/hwmon/w83793.c @@ -1590,7 +1590,7 @@ w83793_detect_subclients(struct i2c_client *client) data->lm75[0] = devm_i2c_new_dummy_device(&client->dev, adapter, 0x48 + (tmp & 0x7)); if (!(tmp & 0x80)) { - if (!IS_ERR(data->lm75[0]) + if (!IS_ERR_OR_NULL(data->lm75[0]) && ((tmp & 0x7) == ((tmp >> 4) & 0x7))) { dev_err(&client->dev, "duplicate addresses 0x%x, " -- 2.17.1