Re: [PATCH] selftests/timers: Fix integer overlow errors on 32 bit systems

[John Stultz]

On Tue, Jun 3, 2025 at 1:10 PM Terry Tritton <terry.tritton@xxxxxxxxxx> wrote:
>
> The use of NSEC_PER_SEC (1000000000L) as defined in include/vdso/time64.h
> causes several integer overflow warnings and test errors on 32 bit
> architectures.
>
> Use a long long instead of long to prevent integer overflow when
> converting seconds to nanoseconds.
>
> Signed-off-by: Terry Tritton <terry.tritton@xxxxxxxxxx>

Needs a Fixes: tag?

> ---
>  tools/testing/selftests/timers/adjtick.c             | 5 ++++-
>  tools/testing/selftests/timers/alarmtimer-suspend.c  | 4 +++-
>  tools/testing/selftests/timers/inconsistency-check.c | 4 +++-
>  tools/testing/selftests/timers/leap-a-day.c          | 4 +++-
>  tools/testing/selftests/timers/mqueue-lat.c          | 3 ++-
>  tools/testing/selftests/timers/nanosleep.c           | 4 +++-
>  tools/testing/selftests/timers/nsleep-lat.c          | 4 +++-
>  tools/testing/selftests/timers/posix_timers.c        | 5 ++++-
>  tools/testing/selftests/timers/raw_skew.c            | 4 +++-
>  tools/testing/selftests/timers/set-2038.c            | 4 +++-
>  tools/testing/selftests/timers/set-timer-lat.c       | 4 +++-
>  tools/testing/selftests/timers/valid-adjtimex.c      | 5 ++++-
>  12 files changed, 38 insertions(+), 12 deletions(-)
>
> diff --git a/tools/testing/selftests/timers/adjtick.c b/tools/testing/selftests/timers/adjtick.c
> index 777d9494b683..b5929c33b632 100644
> --- a/tools/testing/selftests/timers/adjtick.c
> +++ b/tools/testing/selftests/timers/adjtick.c
> @@ -22,10 +22,13 @@
>  #include <sys/time.h>
>  #include <sys/timex.h>
>  #include <time.h>
> -#include <include/vdso/time64.h>
>
>  #include "../kselftest.h"
>
> +/* define NSEC_PER_SEC as long long to avoid overflow on 32 bit architectures*/
> +#define NSEC_PER_SEC   1000000000LL
> +#define USEC_PER_SEC   1000000LL
> +
>  #define MILLION                        1000000
>
>  long systick;
> diff --git a/tools/testing/selftests/timers/alarmtimer-suspend.c b/tools/testing/selftests/timers/alarmtimer-suspend.c
> index a9ef76ea6051..b5799df271ae 100644
> --- a/tools/testing/selftests/timers/alarmtimer-suspend.c
> +++ b/tools/testing/selftests/timers/alarmtimer-suspend.c
> @@ -28,10 +28,12 @@
>  #include <signal.h>
>  #include <stdlib.h>
>  #include <pthread.h>
> -#include <include/vdso/time64.h>
>  #include <errno.h>
>  #include "../kselftest.h"
>
> +/* define NSEC_PER_SEC as long long to avoid overflow on 32 bit architectures*/
> +#define NSEC_PER_SEC   1000000000LL
> +
>  #define UNREASONABLE_LAT (NSEC_PER_SEC * 5) /* hopefully we resume in 5 secs */

So this seems to be undoing commit 80fa614e2fbc ("selftests: timers:
Remove local NSEC_PER_SEC and USEC_PER_SEC defines")

Would it make more sense to fix the NSEC_PER_SEC definition in time64.h to a LL?

thanks
-john