hwmon: (w83627ehf) Get rid of smatch warnings

The smatch static code analyzer complains:

drivers/hwmon/w83627ehf.c:911 w83627ehf_update_device() error: buffer overflow 'W83627EHF_REG_TEMP_OFFSET' 3 <= 8
drivers/hwmon/w83627ehf.c:909 w83627ehf_update_device() error: buffer overflow 'data->temp_offset' 3 <= 8
drivers/hwmon/w83627ehf.c:2672 w83627ehf_resume() error: buffer overflow 'W83627EHF_REG_TEMP_OFFSET' 3 <= 8
drivers/hwmon/w83627ehf.c:2673 w83627ehf_resume() error: buffer overflow 'data->temp_offset' 3 <= 8

A deeper analysis of the code shows that these are false positives, as
only the lower 3 bits of data->have_temp_offset can be set so the
write is never attempted with i >= 3. However this shows that the code
isn't very robust and future changes could easily introduce a buffer
overflow. So let's add a safety check to prevent that and make smatch
happy.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Peter Huewe <PeterHuewe@gmx.de>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
This commit is contained in:
Jean Delvare 2012-12-19 22:17:00 +01:00 committed by Jean Delvare
parent 8f3c7c547d
commit 45633fb370

View File

@ -905,6 +905,8 @@ static struct w83627ehf_data *w83627ehf_update_device(struct device *dev)
data->temp_max_hyst[i]
= w83627ehf_read_temp(data,
data->reg_temp_hyst[i]);
if (i > 2)
continue;
if (data->have_temp_offset & (1 << i))
data->temp_offset[i]
= w83627ehf_read_value(data,
@ -2670,6 +2672,8 @@ static int w83627ehf_resume(struct device *dev)
if (data->reg_temp_hyst[i])
w83627ehf_write_temp(data, data->reg_temp_hyst[i],
data->temp_max_hyst[i]);
if (i > 2)
continue;
if (data->have_temp_offset & (1 << i))
w83627ehf_write_value(data,
W83627EHF_REG_TEMP_OFFSET[i],