2021-03-29 22:00:43

by Gustavo A. R. Silva

Subject: [PATCH][next] iio: hrtimer-trigger: Fix potential integer overflow in iio_hrtimer_store_sampling_frequency

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 <[email protected]>
---
drivers/iio/trigger/iio-trig-hrtimer.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/iio/trigger/iio-trig-hrtimer.c b/drivers/iio/trigger/iio-trig-hrtimer.c
index 51e362f091c2..716c795d08fb 100644
--- 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;
--
2.27.0

2021-04-06 04:03:16

by Jonathan Cameron

Subject: Re: [PATCH][next] iio: hrtimer-trigger: Fix potential integer overflow in iio_hrtimer_store_sampling_frequency

On Mon, 29 Mar 2021 15:58:17 -0500
"Gustavo A. R. Silva" <[email protected]> wrote:

> 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 <[email protected]>

Thanks, Applied to the togreg branch of iio.git and pushed out as testing
for 0-day to poke at it.

Thanks,

Jonathan

> ---
> drivers/iio/trigger/iio-trig-hrtimer.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/iio/trigger/iio-trig-hrtimer.c b/drivers/iio/trigger/iio-trig-hrtimer.c
> index 51e362f091c2..716c795d08fb 100644
> --- 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;

2021-04-06 18:58:48

by Gustavo A. R. Silva

Subject: Re: [PATCH][next] iio: hrtimer-trigger: Fix potential integer overflow in iio_hrtimer_store_sampling_frequency

On 4/5/21 11:26, Jonathan Cameron wrote:
> On Mon, 29 Mar 2021 15:58:17 -0500
> "Gustavo A. R. Silva" <[email protected]> wrote:
>
>> 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 <[email protected]>
>
> Thanks, Applied to the togreg branch of iio.git and pushed out as testing
> for 0-day to poke at it.

Awesome. :)

Thanks, Jonathan.

--
Gustavo