iio: hrtimer-trigger: Fix potential integer overflow in iio_hrtimer_store_sampling_fr...

Add suffix ULL to constant 1000 in order to avoid a potential integer
overflow and give the compiler complete information about the proper
arithmetic to use. Notice that this constant is being used in a context
that expects an expression of type unsigned long long, but it's
currently evaluated using 32-bit arithmetic.

Addresses-Coverity-ID: 1503062 ("Unintentional integer overflow")
Fixes: dafcf4ed8392 ("iio: hrtimer: Allow sub Hz granularity")
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Link: https://lore.kernel.org/r/20210329205817.GA188755@embeddedor
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

diff --git a/drivers/iio/trigger/iio-trig-hrtimer.c b/drivers/iio/trigger/iio-trig-hrtimer.c
index 51e362f..716c795 100644 (file)
--- a/drivers/iio/trigger/iio-trig-hrtimer.c
+++ b/drivers/iio/trigger/iio-trig-hrtimer.c
@@ -63,7 +63,7 @@ ssize_t iio_hrtimer_store_sampling_frequency(struct device *dev,
        if (integer < 0 || fract < 0)
                return -ERANGE;
 
-       val = fract + 1000 * integer;  /* mHz */
+       val = fract + 1000ULL * integer;  /* mHz */
 
        if (!val || val > UINT_MAX)
                return -EINVAL;