From: Guenter Roeck <linux@roeck-us.net>
Date: Sun, 7 Jul 2024 06:50:08 +0000 (-0700)
Subject: hwmon: (nct6775-core) Fix underflows seen when writing limit attributes
X-Git-Tag: v5.10.226~49
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=8a1e958e26640ce015abdbb75c8896301b9bf398;p=thirdparty%2Fkernel%2Fstable.git

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

[ Upstream commit 0403e10bf0824bf0ec2bb135d4cf1c0cc3bf4bf0 ]

DIV_ROUND_CLOSEST() after kstrtol() results in an underflow if a large
negative number such as -9223372036854775808 is provided by the user.
Fix it by reordering clamp_val() and DIV_ROUND_CLOSEST() operations.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---

diff --git a/drivers/hwmon/nct6775.c b/drivers/hwmon/nct6775.c
index 5bd15622a85f9..3645a19cdaf4d 100644
--- a/drivers/hwmon/nct6775.c
+++ b/drivers/hwmon/nct6775.c
@@ -2374,7 +2374,7 @@ store_temp_offset(struct device *dev, struct device_attribute *attr,
 	if (err < 0)
 		return err;
 
-	val = clamp_val(DIV_ROUND_CLOSEST(val, 1000), -128, 127);
+	val = DIV_ROUND_CLOSEST(clamp_val(val, -128000, 127000), 1000);
 
 	mutex_lock(&data->update_lock);
 	data->temp_offset[nr] = val;