From patchwork Mon Apr 9 09:10:44 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Benjamin Tissoires X-Patchwork-Id: 10330855 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 83C056020F for ; Mon, 9 Apr 2018 09:13:20 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 7DD9A28A7A for ; Mon, 9 Apr 2018 09:13:20 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 72D7928A80; Mon, 9 Apr 2018 09:13:20 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00, MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 1AA1628A7A for ; Mon, 9 Apr 2018 09:13:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752506AbeDIJNG (ORCPT ); Mon, 9 Apr 2018 05:13:06 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:57798 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1750863AbeDIJLG (ORCPT ); Mon, 9 Apr 2018 05:11:06 -0400 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.rdu2.redhat.com [10.11.54.5]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id AEBB540201A1; Mon, 9 Apr 2018 09:11:05 +0000 (UTC) Received: from plouf.banquise.eu.com (ovpn-117-29.ams2.redhat.com [10.36.117.29]) by smtp.corp.redhat.com (Postfix) with ESMTP id 0F6A5D7E07; Mon, 9 Apr 2018 09:11:03 +0000 (UTC) From: Benjamin Tissoires To: Dmitry Torokhov Cc: kt.liao@emc.com.tw, Oliver Haessler , Benjamin Berg , Rob Herring , devicetree@vger.kernel.org, linux-input@vger.kernel.org, linux-kernel@vger.kernel.org, Benjamin Tissoires , stable@vger.kernel.org Subject: [PATCH v2 2/9] input: elan_i2c_smbus - fix corrupted stack Date: Mon, 9 Apr 2018 11:10:44 +0200 Message-Id: <20180409091051.2944-3-benjamin.tissoires@redhat.com> In-Reply-To: <20180409091051.2944-1-benjamin.tissoires@redhat.com> References: <20180409091051.2944-1-benjamin.tissoires@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.11.54.5 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.6]); Mon, 09 Apr 2018 09:11:05 +0000 (UTC) X-Greylist: inspected by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.6]); Mon, 09 Apr 2018 09:11:05 +0000 (UTC) for IP:'10.11.54.5' DOMAIN:'int-mx05.intmail.prod.int.rdu2.redhat.com' HELO:'smtp.corp.redhat.com' FROM:'benjamin.tissoires@redhat.com' RCPT:'' Sender: linux-input-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-input@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP New ICs (like the one on the Lenovo T480s) answer to ETP_SMBUS_IAP_VERSION_CMD 4 bytes instead of 3. This corrupts the stack as i2c_smbus_read_block_data() uses the values returned by the i2c device to know how many data it need to return. i2c_smbus_read_block_data() can read up to 32 bytes (I2C_SMBUS_BLOCK_MAX) and there is no safeguard on how many bytes are provided in the return value. Ensure we always have enough space for any future firmware. Also 0-initialize the values to prevent any access to uninitialized memory. Cc: # v4.4.x, v4.9.x, v4.14.x, v4.15.x, v4.16.x Signed-off-by: Benjamin Tissoires --- no changes in v2 drivers/input/mouse/elan_i2c_smbus.c | 22 +++++++++++----------- 1 file changed, 11 insertions(+), 11 deletions(-) diff --git a/drivers/input/mouse/elan_i2c_smbus.c b/drivers/input/mouse/elan_i2c_smbus.c index 29f99529b187..cfcb32559925 100644 --- a/drivers/input/mouse/elan_i2c_smbus.c +++ b/drivers/input/mouse/elan_i2c_smbus.c @@ -130,7 +130,7 @@ static int elan_smbus_get_baseline_data(struct i2c_client *client, bool max_baseline, u8 *value) { int error; - u8 val[3]; + u8 val[I2C_SMBUS_BLOCK_MAX] = {0}; error = i2c_smbus_read_block_data(client, max_baseline ? @@ -149,7 +149,7 @@ static int elan_smbus_get_version(struct i2c_client *client, bool iap, u8 *version) { int error; - u8 val[3]; + u8 val[I2C_SMBUS_BLOCK_MAX] = {0}; error = i2c_smbus_read_block_data(client, iap ? ETP_SMBUS_IAP_VERSION_CMD : @@ -170,7 +170,7 @@ static int elan_smbus_get_sm_version(struct i2c_client *client, u8 *clickpad) { int error; - u8 val[3]; + u8 val[I2C_SMBUS_BLOCK_MAX] = {0}; error = i2c_smbus_read_block_data(client, ETP_SMBUS_SM_VERSION_CMD, val); @@ -188,7 +188,7 @@ static int elan_smbus_get_sm_version(struct i2c_client *client, static int elan_smbus_get_product_id(struct i2c_client *client, u16 *id) { int error; - u8 val[3]; + u8 val[I2C_SMBUS_BLOCK_MAX] = {0}; error = i2c_smbus_read_block_data(client, ETP_SMBUS_UNIQUEID_CMD, val); @@ -205,7 +205,7 @@ static int elan_smbus_get_checksum(struct i2c_client *client, bool iap, u16 *csum) { int error; - u8 val[3]; + u8 val[I2C_SMBUS_BLOCK_MAX] = {0}; error = i2c_smbus_read_block_data(client, iap ? ETP_SMBUS_FW_CHECKSUM_CMD : @@ -226,7 +226,7 @@ static int elan_smbus_get_max(struct i2c_client *client, { int ret; int error; - u8 val[3]; + u8 val[I2C_SMBUS_BLOCK_MAX] = {0}; ret = i2c_smbus_read_block_data(client, ETP_SMBUS_RANGE_CMD, val); if (ret != 3) { @@ -246,7 +246,7 @@ static int elan_smbus_get_resolution(struct i2c_client *client, { int ret; int error; - u8 val[3]; + u8 val[I2C_SMBUS_BLOCK_MAX] = {0}; ret = i2c_smbus_read_block_data(client, ETP_SMBUS_RESOLUTION_CMD, val); if (ret != 3) { @@ -267,7 +267,7 @@ static int elan_smbus_get_num_traces(struct i2c_client *client, { int ret; int error; - u8 val[3]; + u8 val[I2C_SMBUS_BLOCK_MAX] = {0}; ret = i2c_smbus_read_block_data(client, ETP_SMBUS_XY_TRACENUM_CMD, val); if (ret != 3) { @@ -294,7 +294,7 @@ static int elan_smbus_iap_get_mode(struct i2c_client *client, { int error; u16 constant; - u8 val[3]; + u8 val[I2C_SMBUS_BLOCK_MAX] = {0}; error = i2c_smbus_read_block_data(client, ETP_SMBUS_IAP_CTRL_CMD, val); if (error < 0) { @@ -345,7 +345,7 @@ static int elan_smbus_prepare_fw_update(struct i2c_client *client) int len; int error; enum tp_mode mode; - u8 val[3]; + u8 val[I2C_SMBUS_BLOCK_MAX] = {0}; u8 cmd[4] = {0x0F, 0x78, 0x00, 0x06}; u16 password; @@ -419,7 +419,7 @@ static int elan_smbus_write_fw_block(struct i2c_client *client, struct device *dev = &client->dev; int error; u16 result; - u8 val[3]; + u8 val[I2C_SMBUS_BLOCK_MAX] = {0}; /* * Due to the limitation of smbus protocol limiting