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| author | Kangjie Lu <kjlu@umn.edu> | 2018-12-21 13:01:33 -0600 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-02-20 10:13:12 +0100 |
| commit | 259c502d0a0fee860097ed5fa0061223a302003b (patch) | |
| tree | 225f641d2735d0ceb8fba447feb6be6b96fc8bb4 /drivers/hwmon | |
| parent | 8ba3a4eec0a5ec5428f431ec9fe35e3c6cd08ce1 (diff) | |
| download | linux-stable-259c502d0a0fee860097ed5fa0061223a302003b.tar.gz linux-stable-259c502d0a0fee860097ed5fa0061223a302003b.tar.bz2 linux-stable-259c502d0a0fee860097ed5fa0061223a302003b.zip | |
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 <kjlu@umn.edu>
[groeck: One variable for return values is enough]
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'drivers/hwmon')
| -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 4bcd9b882948..47ddae6b7038 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 */ |