[char-misc-next 2/6] mei: ioctl: use sizeof of variable instead of struct type

From: Tomas Winkler
Date: Thu Jul 23 2020 - 10:59:48 EST


Use sizeof(connect_data))) instead of
sizeof(struct mei_connect_client_data) when copying data
between user space and kernel.

There is a possibility of bug when variable type has changed but
corresponding struct passed to the sizeof has not.

Cc: Gustavo A. R. Silva <gustavoars@xxxxxxxxxx>
Signed-off-by: Tomas Winkler <tomas.winkler@xxxxxxxxx>
---
drivers/misc/mei/main.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/misc/mei/main.c b/drivers/misc/mei/main.c
index f17297f2943d..05e6ad6d4d54 100644
--- a/drivers/misc/mei/main.c
+++ b/drivers/misc/mei/main.c
@@ -1,6 +1,6 @@
// SPDX-License-Identifier: GPL-2.0
/*
- * Copyright (c) 2003-2018, Intel Corporation. All rights reserved.
+ * Copyright (c) 2003-2020, Intel Corporation. All rights reserved.
* Intel Management Engine Interface (Intel MEI) Linux driver
*/

@@ -476,7 +476,7 @@ static long mei_ioctl(struct file *file, unsigned int cmd, unsigned long data)
case IOCTL_MEI_CONNECT_CLIENT:
dev_dbg(dev->dev, ": IOCTL_MEI_CONNECT_CLIENT.\n");
if (copy_from_user(&connect_data, (char __user *)data,
- sizeof(struct mei_connect_client_data))) {
+ sizeof(connect_data))) {
dev_dbg(dev->dev, "failed to copy data from userland\n");
rets = -EFAULT;
goto out;
@@ -488,7 +488,7 @@ static long mei_ioctl(struct file *file, unsigned int cmd, unsigned long data)

/* if all is ok, copying the data back to user. */
if (copy_to_user((char __user *)data, &connect_data,
- sizeof(struct mei_connect_client_data))) {
+ sizeof(connect_data))) {
dev_dbg(dev->dev, "failed to copy data to userland\n");
rets = -EFAULT;
goto out;
--
2.25.4