From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.kernel.org ([198.145.29.99]:32914 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751842AbeFEREE (ORCPT ); Tue, 5 Jun 2018 13:04:04 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Benjamin Tissoires , KT Liao , Dmitry Torokhov Subject: [PATCH 4.4 07/37] Input: elan_i2c_smbus - fix corrupted stack Date: Tue, 5 Jun 2018 19:01:12 +0200 Message-Id: <20180605170109.327128892@linuxfoundation.org> In-Reply-To: <20180605170108.884872354@linuxfoundation.org> References: <20180605170108.884872354@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: stable-owner@vger.kernel.org List-ID: 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Benjamin Tissoires commit 40f7090bb1b4ec327ea1e1402ff5783af5b35195 upstream. 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 Acked-by: KT Liao Signed-off-by: Dmitry Torokhov Signed-off-by: Greg Kroah-Hartman --- drivers/input/mouse/elan_i2c_smbus.c | 22 +++++++++++----------- 1 file changed, 11 insertions(+), 11 deletions(-) --- 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( 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 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 : @@ -169,7 +169,7 @@ static int elan_smbus_get_sm_version(str u8 *ic_type, u8 *version) { 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); @@ -186,7 +186,7 @@ static int elan_smbus_get_sm_version(str 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); @@ -203,7 +203,7 @@ static int elan_smbus_get_checksum(struc 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 : @@ -223,7 +223,7 @@ static int elan_smbus_get_max(struct i2c unsigned int *max_x, unsigned int *max_y) { int error; - u8 val[3]; + u8 val[I2C_SMBUS_BLOCK_MAX] = {0}; error = i2c_smbus_read_block_data(client, ETP_SMBUS_RANGE_CMD, val); if (error) { @@ -241,7 +241,7 @@ static int elan_smbus_get_resolution(str u8 *hw_res_x, u8 *hw_res_y) { int error; - u8 val[3]; + u8 val[I2C_SMBUS_BLOCK_MAX] = {0}; error = i2c_smbus_read_block_data(client, ETP_SMBUS_RESOLUTION_CMD, val); @@ -261,7 +261,7 @@ static int elan_smbus_get_num_traces(str unsigned int *y_traces) { int error; - u8 val[3]; + u8 val[I2C_SMBUS_BLOCK_MAX] = {0}; error = i2c_smbus_read_block_data(client, ETP_SMBUS_XY_TRACENUM_CMD, val); @@ -288,7 +288,7 @@ static int elan_smbus_iap_get_mode(struc { 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) { @@ -339,7 +339,7 @@ static int elan_smbus_prepare_fw_update( 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; @@ -413,7 +413,7 @@ static int elan_smbus_write_fw_block(str 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