[PATCH v2 02/17] iio: accel: mma9553: check input value for activity period

Irina Tirdea
2015-04-13T15:40:49Z

When setting the activity period, the value introduced by
the user in sysfs is not checked for validity.

Add a boundary check so that only allowed values are
reported as successfully written to device.

Signed-off-by: Irina Tirdea <irina.tirdea@intel.com>
Reported-by: Hartmut Knaack <knaack.h@gmx.de>
---
drivers/iio/accel/mma9553.c | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/drivers/iio/accel/mma9553.c b/drivers/iio/accel/mma9553.c
index 607dbfc..03120fb 100644
--- a/drivers/iio/accel/mma9553.c
+++ b/drivers/iio/accel/mma9553.c
@@ -54,6 +54,7 @@
#define MMA9553_MASK_CONF_STEPCOALESCE GENMASK(7, 0)

#define MMA9553_REG_CONF_ACTTHD 0x0E
+#define MMA9553_MAX_ACTTHD GENMASK(15, 0)

/* Pedometer status registers (R-only) */
#define MMA9553_REG_STATUS 0x00
@@ -869,6 +870,9 @@ static int mma9553_write_event_value(struct iio_dev *indio_dev,
case IIO_EV_INFO_PERIOD:
switch (chan->type) {
case IIO_ACTIVITY:
+ if (val < 0 || val > MMA9553_ACTIVITY_THD_TO_SEC(
+ MMA9553_MAX_ACTTHD))
+ return -EINVAL;
mutex_lock(&data->mutex);
ret = mma9553_set_config(data, MMA9553_REG_CONF_ACTTHD,
&data->conf.actthd,
--
1.9.1