Re: [PATCH] staging: android/vsoc: stop using 'timespec'

From: Alistair Strachan
Date: Thu Jun 21 2018 - 18:04:39 EST


On Mon, Jun 18, 2018 at 8:09 AM Arnd Bergmann <arnd@xxxxxxxx> wrote:
>
> The timespec structure suffers from the y2038 overflow and should not
> be used. This changes handle_vsoc_cond_wait() to use ktime_t directly.
>
> Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>

Tested-by: Alistair Strachan <astrachan@xxxxxxxxxx>

> ---
> drivers/staging/android/vsoc.c | 11 +++++------
> 1 file changed, 5 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/staging/android/vsoc.c b/drivers/staging/android/vsoc.c
> index 806beda1040b..22571abcaa4e 100644
> --- a/drivers/staging/android/vsoc.c
> +++ b/drivers/staging/android/vsoc.c
> @@ -405,7 +405,7 @@ static int handle_vsoc_cond_wait(struct file *filp, struct vsoc_cond_wait *arg)
> int ret = 0;
> struct vsoc_device_region *region_p = vsoc_region_from_filep(filp);
> atomic_t *address = NULL;
> - struct timespec ts;
> + ktime_t wake_time;
>
> /* Ensure that the offset is aligned */
> if (arg->offset & (sizeof(uint32_t) - 1))
> @@ -433,14 +433,13 @@ static int handle_vsoc_cond_wait(struct file *filp, struct vsoc_cond_wait *arg)
> * We do things this way to flatten differences between 32 bit
> * and 64 bit timespecs.
> */
> - ts.tv_sec = arg->wake_time_sec;
> - ts.tv_nsec = arg->wake_time_nsec;
> -
> - if (!timespec_valid(&ts))
> + if (arg->wake_time_nsec >= NSEC_PER_SEC)
> return -EINVAL;
> + wake_time = ktime_set(arg->wake_time_sec, arg->wake_time_nsec);
> +
> hrtimer_init_on_stack(&to->timer, CLOCK_MONOTONIC,
> HRTIMER_MODE_ABS);
> - hrtimer_set_expires_range_ns(&to->timer, timespec_to_ktime(ts),
> + hrtimer_set_expires_range_ns(&to->timer, wake_time,
> current->timer_slack_ns);
>
> hrtimer_init_sleeper(to, current);
> --
> 2.9.0
>