From c1ec0cabc36718efc7fe8b4157d41b82d08ec1d2 Mon Sep 17 00:00:00 2001 From: Dan Carpenter Date: Fri, 21 Jan 2022 14:55:43 +0300 Subject: [PATCH] hwmon: (adt7470) Prevent divide by zero in adt7470_fan_write() The "val" variable is controlled by the user and comes from hwmon_attr_store(). The FAN_RPM_TO_PERIOD() macro divides by "val" so a zero will crash the system. Check for that and return -EINVAL. Negatives are also invalid so return -EINVAL for those too. Fixes: fc958a61ff6d ("hwmon: (adt7470) Convert to devm_hwmon_device_register_with_info API") Signed-off-by: Dan Carpenter Signed-off-by: Guenter Roeck --- drivers/hwmon/adt7470.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/hwmon/adt7470.c b/drivers/hwmon/adt7470.c index d519aca4a9d6..fb6d14d213a1 100644 --- a/drivers/hwmon/adt7470.c +++ b/drivers/hwmon/adt7470.c @@ -662,6 +662,9 @@ static int adt7470_fan_write(struct device *dev, u32 attr, int channel, long val struct adt7470_data *data = dev_get_drvdata(dev); int err; + if (val <= 0) + return -EINVAL; + val = FAN_RPM_TO_PERIOD(val); val = clamp_val(val, 1, 65534);