Re: [PATCH] hwmon: max31790: fix dereference of ERR_PTR

From: Guenter Roeck
Date: Wed Sep 16 2015 - 10:10:22 EST


On 09/16/2015 07:02 AM, Sudip Mukherjee wrote:
max31790_update_device() return the error code in ERR_PTR. We were
checking if it has returned error or not but before checking we have
dereferenced it.

Signed-off-by: Sudip Mukherjee <sudip@xxxxxxxxxxxxxxx>

Good catch. Applied.

Thanks,
Guenter

---
drivers/hwmon/max31790.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/hwmon/max31790.c b/drivers/hwmon/max31790.c
index f129668..69c0ac8 100644
--- a/drivers/hwmon/max31790.c
+++ b/drivers/hwmon/max31790.c
@@ -174,12 +174,12 @@ static ssize_t get_fan(struct device *dev,
{
struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
struct max31790_data *data = max31790_update_device(dev);
- int sr = get_tach_period(data->fan_dynamics[attr->index]);
- int rpm;
+ int sr, rpm;

if (IS_ERR(data))
return PTR_ERR(data);

+ sr = get_tach_period(data->fan_dynamics[attr->index]);
rpm = RPM_FROM_REG(data->tach[attr->index], sr);

return sprintf(buf, "%d\n", rpm);
@@ -190,12 +190,12 @@ static ssize_t get_fan_target(struct device *dev,
{
struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
struct max31790_data *data = max31790_update_device(dev);
- int sr = get_tach_period(data->fan_dynamics[attr->index]);
- int rpm;
+ int sr, rpm;

if (IS_ERR(data))
return PTR_ERR(data);

+ sr = get_tach_period(data->fan_dynamics[attr->index]);
rpm = RPM_FROM_REG(data->target_count[attr->index], sr);

return sprintf(buf, "%d\n", rpm);


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/