Re: [PATCH 1/3] Input: elan_i2c_smbus - cast sizeof to int for comparison
From: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Date: 2018-08-01 23:04:01
Also in:
kernel-janitors, lkml
On Sun, Jul 01, 2018 at 07:32:03PM +0200, Julia Lawall wrote:
Comparing an int to a size, which is unsigned, causes the int to become unsigned, giving the wrong result. i2c_smbus_read_block_data can return the result of i2c_smbus_xfer, whih can return a negative error code. A simplified version of the semantic match that finds this problem is as follows: (http://coccinelle.lip6.fr/) // <smpl> @@ int x; expression e,e1; identifier f; @@ *x = f(...); ... when != x = e1 when != if (x < 0 || ...) { ... return ...; } *x < sizeof(e) // </smpl> Signed-off-by: Julia Lawall <redacted>
Applied, thank you.
quoted hunk ↗ jump to hunk
--- drivers/input/mouse/elan_i2c_smbus.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)diff --git a/drivers/input/mouse/elan_i2c_smbus.c b/drivers/input/mouse/elan_i2c_smbus.c index c060d27..88e315d 100644 --- a/drivers/input/mouse/elan_i2c_smbus.c +++ b/drivers/input/mouse/elan_i2c_smbus.c@@ -387,7 +387,7 @@ static int elan_smbus_prepare_fw_update(struct i2c_client *client) len = i2c_smbus_read_block_data(client, ETP_SMBUS_IAP_PASSWORD_READ, val); - if (len < sizeof(u16)) { + if (len < (int)sizeof(u16)) { error = len < 0 ? len : -EIO; dev_err(dev, "failed to read iap password: %d\n", error);
-- Dmitry