From: Guenter Roeck <linux@roeck-us.net>
Date: Wed, 30 Jul 2014 03:48:59 +0000 (-0700)
Subject: hwmon: (lm78) Fix overflow problems seen when writing large temperature limits
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=1074d683a51f1aded3562add9ef313e75d557327;p=linux-beck.git

hwmon: (lm78) Fix overflow problems seen when writing large temperature limits

On platforms with sizeof(int) < sizeof(long), writing a temperature
limit larger than MAXINT will result in unpredictable limit values
written to the chip. Avoid auto-conversion from long to int to fix
the problem.

Cc: Axel Lin <axel.lin@ingics.com>
Cc: stable@vger.kernel.org
Reviewed-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
---

diff --git a/drivers/hwmon/lm78.c b/drivers/hwmon/lm78.c
index 9efadfc851bc..c1eb464f0fd0 100644
--- a/drivers/hwmon/lm78.c
+++ b/drivers/hwmon/lm78.c
@@ -108,7 +108,7 @@ static inline int FAN_FROM_REG(u8 val, int div)
  * TEMP: mC (-128C to +127C)
  * REG: 1C/bit, two's complement
  */
-static inline s8 TEMP_TO_REG(int val)
+static inline s8 TEMP_TO_REG(long val)
 {
 	int nval = clamp_val(val, -128000, 127000) ;
 	return nval < 0 ? (nval - 500) / 1000 : (nval + 500) / 1000;