hwmon: (nct6775-core) Fix overflows seen when writing limit attributes

DIV_ROUND_CLOSEST() after kstrtoul() results in an overflow if a large
number such as 18446744073709551615 is provided by the user.
Fix it by reordering clamp_val() and DIV_ROUND_CLOSEST() operations.

Signed-off-by: Pei Xiao <xiaopei01@kylinos.cn>
Fixes: c3963bc0a0cf ("hwmon: (nct6775) Split core and platform driver")
Message-ID: <7d5084cea33f7c0fd0578c59adfff71f93de94d9.1731375425.git.xiaopei01@kylinos.cn>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

diff --git a/drivers/hwmon/nct6775-core.c b/drivers/hwmon/nct6775-core.c
index 934fed3dd58661ef6c2ef7d3d0abc34a545a501a..ee04795b98aabe70f7900da4d3217433943a26cf 100644 (file)
--- a/drivers/hwmon/nct6775-core.c
+++ b/drivers/hwmon/nct6775-core.c
@@ -2878,8 +2878,7 @@ store_target_temp(struct device *dev, struct device_attribute *attr,
        if (err < 0)
                return err;
 
-       val = clamp_val(DIV_ROUND_CLOSEST(val, 1000), 0,
-                       data->target_temp_mask);
+       val = DIV_ROUND_CLOSEST(clamp_val(val, 0, data->target_temp_mask * 1000), 1000);
 
        mutex_lock(&data->update_lock);
        data->target_temp[nr] = val;
@@ -2959,7 +2958,7 @@ store_temp_tolerance(struct device *dev, struct device_attribute *attr,
                return err;
 
        /* Limit tolerance as needed */
-       val = clamp_val(DIV_ROUND_CLOSEST(val, 1000), 0, data->tolerance_mask);
+       val = DIV_ROUND_CLOSEST(clamp_val(val, 0, data->tolerance_mask * 1000), 1000);
 
        mutex_lock(&data->update_lock);
        data->temp_tolerance[index][nr] = val;
@@ -3085,7 +3084,7 @@ store_weight_temp(struct device *dev, struct device_attribute *attr,
        if (err < 0)
                return err;
 
-       val = clamp_val(DIV_ROUND_CLOSEST(val, 1000), 0, 255);
+       val = DIV_ROUND_CLOSEST(clamp_val(val, 0, 255000), 1000);
 
        mutex_lock(&data->update_lock);
        data->weight_temp[index][nr] = val;