Re: [patch] iio: tsl2583: make array large enough

From: walter harms
Date: Thu Nov 24 2016 - 11:54:39 EST




Am 24.11.2016 16:48, schrieb Brian Masney:
> On Thu, Nov 24, 2016 at 04:38:07PM +0300, Dan Carpenter wrote:
>> This array is supposed to have 10 elements. Smatch complains that with
>> the current code we can have n == max_ints and read beyond the end of
>> the array.
>>
>> Fixes: ac4f6eee8fe8 ("staging: iio: TAOS tsl258x: Device driver")
>> Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
>>
>> diff --git a/drivers/iio/light/tsl2583.c b/drivers/iio/light/tsl2583.c
>> index 0b87f6a..a78b602 100644
>> --- a/drivers/iio/light/tsl2583.c
>> +++ b/drivers/iio/light/tsl2583.c
>> @@ -565,7 +565,7 @@ static ssize_t in_illuminance_lux_table_store(struct device *dev,
>> struct iio_dev *indio_dev = dev_to_iio_dev(dev);
>> struct tsl2583_chip *chip = iio_priv(indio_dev);
>> const unsigned int max_ints = TSL2583_MAX_LUX_TABLE_ENTRIES * 3;
>> - int value[TSL2583_MAX_LUX_TABLE_ENTRIES * 3];
>> + int value[TSL2583_MAX_LUX_TABLE_ENTRIES * 3 + 1];
>> int ret = -EINVAL;
>> unsigned int n;
>>
>

sorry i did not notice that bevor ..
there is a
max_ints = TSL2583_MAX_LUX_TABLE_ENTRIES * 3

IMHO this should read either:
int value[max_ints+1];
or
max_ints=ARRAY_SIZE(value)-1;

(my personal favorite is dropping max_ints completely).

re,
wh