From 00cab884d0b5b9efb0854457978334eeccc8a0f7 Mon Sep 17 00:00:00 2001 From: Guenter Roeck Date: Fri, 18 Jul 2014 07:31:18 -0700 Subject: [PATCH] hwmon: (smsc47m192) Fix temperature limit and vrm write operations commit 043572d5444116b9d9ad8ae763cf069e7accbc30 upstream. Temperature limit clamps are applied after converting the temperature from milli-degrees C to degrees C, so either the clamp limit needs to be specified in degrees C, not milli-degrees C, or clamping must happen before converting to degrees C. Use the latter method to avoid overflows. vrm is an u8, so the written value needs to be limited to [0, 255]. Cc: Axel Lin Signed-off-by: Guenter Roeck Reviewed-by: Jean Delvare [bwh: Backported to 3.2: - Driver is not using clamp_val(); keep using SENSORS_LIMIT() for consistency - Driver is not using kstrtoul(); make the minimum change to set_vrm() so we can validate the value before assigning] Signed-off-by: Ben Hutchings --- drivers/hwmon/smsc47m192.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/drivers/hwmon/smsc47m192.c b/drivers/hwmon/smsc47m192.c index 40b26673d87f3..7d1373df0f55e 100644 --- a/drivers/hwmon/smsc47m192.c +++ b/drivers/hwmon/smsc47m192.c @@ -84,7 +84,7 @@ static inline u8 IN_TO_REG(unsigned long val, int n) REG: 1C/bit, two's complement */ static inline s8 TEMP_TO_REG(int val) { - return SENSORS_LIMIT(SCALE(val, 1, 1000), -128000, 127000); + return SCALE(SENSORS_LIMIT(val, -128000, 127000), 1, 1000); } static inline int TEMP_FROM_REG(s8 val) @@ -349,7 +349,13 @@ static ssize_t set_vrm(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) { struct smsc47m192_data *data = dev_get_drvdata(dev); - data->vrm = simple_strtoul(buf, NULL, 10); + unsigned long val; + + val = simple_strtoul(buf, NULL, 10); + if (val > 255) + return -EINVAL; + + data->vrm = val; return count; } static DEVICE_ATTR(vrm, S_IRUGO | S_IWUSR, show_vrm, set_vrm); -- 2.47.3