From 59715f4d16c27985b6866ebdced76e4e9cd63c33 Mon Sep 17 00:00:00 2001 From: Guenter Roeck Date: Sun, 4 Dec 2016 18:20:52 -0800 Subject: [PATCH] hwmon: (emcw201) Fix overflows seen when writing into limit attributes Writes into temperature and voltage limit attributes can overflow due to multiplications with unchecked parameters. Also, the input parameter to DIV_ROUND_CLOSEST() needis to be range checked. Reviewed-by: Jean Delvare Signed-off-by: Guenter Roeck --- drivers/hwmon/emc6w201.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/drivers/hwmon/emc6w201.c b/drivers/hwmon/emc6w201.c index f37fe2011640..4aee5adf9ef2 100644 --- a/drivers/hwmon/emc6w201.c +++ b/drivers/hwmon/emc6w201.c @@ -215,12 +215,13 @@ static ssize_t set_in(struct device *dev, struct device_attribute *devattr, if (err < 0) return err; - val = DIV_ROUND_CLOSEST(val * 0xC0, nominal_mv[nr]); + val = clamp_val(val, 0, 255 * nominal_mv[nr] / 192); + val = DIV_ROUND_CLOSEST(val * 192, nominal_mv[nr]); reg = (sf == min) ? EMC6W201_REG_IN_LOW(nr) : EMC6W201_REG_IN_HIGH(nr); mutex_lock(&data->update_lock); - data->in[sf][nr] = clamp_val(val, 0, 255); + data->in[sf][nr] = val; err = emc6w201_write8(client, reg, data->in[sf][nr]); mutex_unlock(&data->update_lock); @@ -252,12 +253,13 @@ static ssize_t set_temp(struct device *dev, struct device_attribute *devattr, if (err < 0) return err; + val = clamp_val(val, -127000, 127000); val = DIV_ROUND_CLOSEST(val, 1000); reg = (sf == min) ? EMC6W201_REG_TEMP_LOW(nr) : EMC6W201_REG_TEMP_HIGH(nr); mutex_lock(&data->update_lock); - data->temp[sf][nr] = clamp_val(val, -127, 127); + data->temp[sf][nr] = val; err = emc6w201_write8(client, reg, data->temp[sf][nr]); mutex_unlock(&data->update_lock);