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| author | Kangjie Lu <kjlu@umn.edu> | 2018-12-21 13:01:33 -0600 |
|---|---|---|
| committer | Guenter Roeck <linux@roeck-us.net> | 2018-12-21 15:37:56 -0800 |
| commit | c9c63915519b1def7043b184680f33c24cd49d7b (patch) | |
| tree | 893bd90f11a1ca968c1b73e86e410fbb1e2237b5 | |
| parent | f9facc24a6441d6a82d6cca942b162a394ecba66 (diff) | |
| download | linux-c9c63915519b1def7043b184680f33c24cd49d7b.tar.gz | |
hwmon: (lm80) fix a missing check of the status of SMBus read
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 <kjlu@umn.edu> [groeck: One variable for return values is enough] Signed-off-by: Guenter Roeck <linux@roeck-us.net>
| -rw-r--r-- | drivers/hwmon/lm80.c | 15 |
1 files changed, 10 insertions, 5 deletions
diff --git a/drivers/hwmon/lm80.c b/drivers/hwmon/lm80.c index 08e3945a6fbf..04f9df0d2341 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 */ |