4.9-stable review patch. If anyone has any objections, please let me know.
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From: Benjamin Tissoires benjamin.tissoires@redhat.com
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: stable@vger.kernel.org # v4.4.x, v4.9.x, v4.14.x, v4.15.x, v4.16.x Signed-off-by: Benjamin Tissoires benjamin.tissoires@redhat.com Acked-by: KT Liao kt.liao@emc.com.tw Signed-off-by: Dmitry Torokhov dmitry.torokhov@gmail.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- 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 : @@ -224,7 +224,7 @@ static int elan_smbus_get_max(struct i2c { 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) { @@ -244,7 +244,7 @@ static int elan_smbus_get_resolution(str { 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) { @@ -265,7 +265,7 @@ static int elan_smbus_get_num_traces(str { 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) { @@ -292,7 +292,7 @@ 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) { @@ -343,7 +343,7 @@ 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;
@@ -417,7 +417,7 @@ 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