hwmon: Prevent some divide by zeros in FAN_TO_REG()

The "rpm * div" operations can overflow here, so this patch adds an
upper limit to rpm to prevent that.  Jean Delvare helped me with this
patch.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Roger Lucas <vt8231@hiddenengine.co.uk>
Cc: stable@vger.kernel.org
Signed-off-by: Jean Delvare <khali@linux-fr.org>

1 files changed, 2 insertions, 0 deletions

diff --git a/drivers/hwmon/sis5595.c b/drivers/hwmon/sis5595.c
index 1404e6319deb..72a889702f0d 100644
--- a/drivers/hwmon/sis5595.c
+++ b/drivers/hwmon/sis5595.c
@@ -141,6 +141,8 @@ static inline u8 FAN_TO_REG(long rpm, int div)
 {
         if (rpm <= 0)
                 return 255;
+        if (rpm > 1350000)
+                return 1;
         return clamp_val((1350000 + rpm * div / 2) / (rpm * div), 1, 254);
 }