patch "iio: inv_mpu6050: Fully validate gyro and accel scale writes" added to staging-next

[<gregkh@linuxfoundation.org>]

This is a note to let you know that I've just added the patch titled

    iio: inv_mpu6050: Fully validate gyro and accel scale writes

to my staging git tree which can be found at
    git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging.git
in the staging-next branch.

The patch will show up in the next release of the linux-next tree
(usually sometime within the next 24 hours during the week.)

The patch will also be merged in the next major kernel release
during the merge window.

If you have any questions about this process, please let me know.


From e09fe9135399807b8397798a53160e055dc6c29f Mon Sep 17 00:00:00 2001
From: Lars-Peter Clausen <lars@metafoo.de>
Date: Mon, 5 Apr 2021 13:44:41 +0200
Subject: iio: inv_mpu6050: Fully validate gyro and accel scale writes

When setting the gyro or accelerometer scale the inv_mpu6050 driver ignores
the integer part of the value. As a result e.g. all of 0.13309, 1.13309,
12345.13309, ... are accepted as a valid gyro scale and 0.13309 is the
scale that gets set in all those cases.

Make sure to check that the integer part of the scale value is 0 and reject
it otherwise.

Fixes: 09a642b78523 ("Invensense MPU6050 Device Driver.")
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Acked-by: Jean-Baptiste Maneyrol <jmaneyrol@invensense.com>
Link: https://lore.kernel.org/r/20210405114441.24167-1-lars@metafoo.de
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
---
 drivers/iio/imu/inv_mpu6050/inv_mpu_core.c | 20 ++++++++++++++------
 1 file changed, 14 insertions(+), 6 deletions(-)

diff --git a/drivers/iio/imu/inv_mpu6050/inv_mpu_core.c b/drivers/iio/imu/inv_mpu6050/inv_mpu_core.c
index cda7b48981c9..6244a07048df 100644
--- a/drivers/iio/imu/inv_mpu6050/inv_mpu_core.c
+++ b/drivers/iio/imu/inv_mpu6050/inv_mpu_core.c
@@ -731,12 +731,16 @@ inv_mpu6050_read_raw(struct iio_dev *indio_dev,
 	}
 }
 
-static int inv_mpu6050_write_gyro_scale(struct inv_mpu6050_state *st, int val)
+static int inv_mpu6050_write_gyro_scale(struct inv_mpu6050_state *st, int val,
+					int val2)
 {
 	int result, i;
 
+	if (val != 0)
+		return -EINVAL;
+
 	for (i = 0; i < ARRAY_SIZE(gyro_scale_6050); ++i) {
-		if (gyro_scale_6050[i] == val) {
+		if (gyro_scale_6050[i] == val2) {
 			result = inv_mpu6050_set_gyro_fsr(st, i);
 			if (result)
 				return result;
@@ -767,13 +771,17 @@ static int inv_write_raw_get_fmt(struct iio_dev *indio_dev,
 	return -EINVAL;
 }
 
-static int inv_mpu6050_write_accel_scale(struct inv_mpu6050_state *st, int val)
+static int inv_mpu6050_write_accel_scale(struct inv_mpu6050_state *st, int val,
+					 int val2)
 {
 	int result, i;
 	u8 d;
 
+	if (val != 0)
+		return -EINVAL;
+
 	for (i = 0; i < ARRAY_SIZE(accel_scale); ++i) {
-		if (accel_scale[i] == val) {
+		if (accel_scale[i] == val2) {
 			d = (i << INV_MPU6050_ACCL_CONFIG_FSR_SHIFT);
 			result = regmap_write(st->map, st->reg->accl_config, d);
 			if (result)
@@ -814,10 +822,10 @@ static int inv_mpu6050_write_raw(struct iio_dev *indio_dev,
 	case IIO_CHAN_INFO_SCALE:
 		switch (chan->type) {
 		case IIO_ANGL_VEL:
-			result = inv_mpu6050_write_gyro_scale(st, val2);
+			result = inv_mpu6050_write_gyro_scale(st, val, val2);
 			break;
 		case IIO_ACCEL:
-			result = inv_mpu6050_write_accel_scale(st, val2);
+			result = inv_mpu6050_write_accel_scale(st, val, val2);
 			break;
 		default:
 			result = -EINVAL;
-- 
2.31.1