From: Kangjie Lu Date: Fri, 21 Dec 2018 19:01:33 +0000 (-0600) Subject: hwmon: (lm80) fix a missing check of the status of SMBus read X-Git-Tag: v4.14.99~71 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=58ddc0c67d113a1081e3c017682b475b75a6bf2c;p=platform%2Fkernel%2Flinux-exynos.git hwmon: (lm80) fix a missing check of the status of SMBus read [ Upstream commit c9c63915519b1def7043b184680f33c24cd49d7b ] If lm80_read_value() fails, it returns a negative number instead of the correct read data. Therefore, we should avoid using the data if it fails. The fix checks if lm80_read_value() fails, and if so, returns with the error number. Signed-off-by: Kangjie Lu [groeck: One variable for return values is enough] Signed-off-by: Guenter Roeck Signed-off-by: Sasha Levin --- diff --git a/drivers/hwmon/lm80.c b/drivers/hwmon/lm80.c index 08e3945..04f9df0 100644 --- a/drivers/hwmon/lm80.c +++ b/drivers/hwmon/lm80.c @@ -360,9 +360,11 @@ static ssize_t set_fan_div(struct device *dev, struct device_attribute *attr, struct i2c_client *client = data->client; unsigned long min, val; u8 reg; - int err = kstrtoul(buf, 10, &val); - if (err < 0) - return err; + int rv; + + rv = kstrtoul(buf, 10, &val); + if (rv < 0) + return rv; /* Save fan_min */ mutex_lock(&data->update_lock); @@ -390,8 +392,11 @@ static ssize_t set_fan_div(struct device *dev, struct device_attribute *attr, return -EINVAL; } - reg = (lm80_read_value(client, LM80_REG_FANDIV) & - ~(3 << (2 * (nr + 1)))) | (data->fan_div[nr] << (2 * (nr + 1))); + rv = lm80_read_value(client, LM80_REG_FANDIV); + if (rv < 0) + return rv; + reg = (rv & ~(3 << (2 * (nr + 1)))) + | (data->fan_div[nr] << (2 * (nr + 1))); lm80_write_value(client, LM80_REG_FANDIV, reg); /* Restore fan_min */