[PATCH 3.16 086/178] hwmon: (asus_atk0110) fix uninitialized data access
From: Ben Hutchings
Date: Sun Jul 16 2017 - 10:43:58 EST
3.16.46-rc1 review patch. If anyone has any objections, please let me know.
------------------
From: Arnd Bergmann <arnd@xxxxxxxx>
commit a2125d02443e9a4e68bcfd9f8004fa23239e8329 upstream.
The latest gcc-7 snapshot adds a warning to point out that when
atk_read_value_old or atk_read_value_new fails, we copy
uninitialized data into sensor->cached_value:
drivers/hwmon/asus_atk0110.c: In function 'atk_input_show':
drivers/hwmon/asus_atk0110.c:651:26: error: 'value' may be used uninitialized in this function [-Werror=maybe-uninitialized]
Adding an error check avoids this. All versions of the driver
are affected.
Fixes: 2c03d07ad54d ("hwmon: Add Asus ATK0110 support")
Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
Reviewed-by: Luca Tettamanti <kronos.it@xxxxxxxxx>
Signed-off-by: Guenter Roeck <linux@xxxxxxxxxxxx>
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
drivers/hwmon/asus_atk0110.c | 3 +++
1 file changed, 3 insertions(+)
--- a/drivers/hwmon/asus_atk0110.c
+++ b/drivers/hwmon/asus_atk0110.c
@@ -646,6 +646,9 @@ static int atk_read_value(struct atk_sen
else
err = atk_read_value_new(sensor, value);
+ if (err)
+ return err;
+
sensor->is_valid = true;
sensor->last_updated = jiffies;
sensor->cached_value = *value;