Re: [PATCH] posix-stubs: use get_timespec64() and put_timespec64()

From: Nicolas Pitre
Date: Fri Oct 13 2017 - 15:23:02 EST


On Fri, 13 Oct 2017, Arnd Bergmann wrote:

> This is a follow-up to commit 5c4994102fb5 ("posix-timers:
> Use get_timespec64() and put_timespec64()"), which left two
> system call using copy_from_user()/copy_to_user(). We can
> change them as well for consistency.
>
> Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>

Acked-by: Nicolas Pitre <nico@xxxxxxxxxx>

> ---
> kernel/time/posix-stubs.c | 20 ++++++++------------
> 1 file changed, 8 insertions(+), 12 deletions(-)
>
> diff --git a/kernel/time/posix-stubs.c b/kernel/time/posix-stubs.c
> index 06f34feb635e..b258bee13b02 100644
> --- a/kernel/time/posix-stubs.c
> +++ b/kernel/time/posix-stubs.c
> @@ -117,8 +117,7 @@ SYSCALL_DEFINE4(clock_nanosleep, const clockid_t, which_clock, int, flags,
> const struct timespec __user *, rqtp,
> struct timespec __user *, rmtp)
> {
> - struct timespec64 t64;
> - struct timespec t;
> + struct timespec64 t;
>
> switch (which_clock) {
> case CLOCK_REALTIME:
> @@ -129,16 +128,15 @@ SYSCALL_DEFINE4(clock_nanosleep, const clockid_t, which_clock, int, flags,
> return -EINVAL;
> }
>
> - if (copy_from_user(&t, rqtp, sizeof (struct timespec)))
> + if (get_timespec64(&t, rqtp))
> return -EFAULT;
> - t64 = timespec_to_timespec64(t);
> - if (!timespec64_valid(&t64))
> + if (!timespec64_valid(&t))
> return -EINVAL;
> if (flags & TIMER_ABSTIME)
> rmtp = NULL;
> current->restart_block.nanosleep.type = rmtp ? TT_NATIVE : TT_NONE;
> current->restart_block.nanosleep.rmtp = rmtp;
> - return hrtimer_nanosleep(&t64, flags & TIMER_ABSTIME ?
> + return hrtimer_nanosleep(&t, flags & TIMER_ABSTIME ?
> HRTIMER_MODE_ABS : HRTIMER_MODE_REL,
> which_clock);
> }
> @@ -203,8 +201,7 @@ COMPAT_SYSCALL_DEFINE4(clock_nanosleep, clockid_t, which_clock, int, flags,
> struct compat_timespec __user *, rqtp,
> struct compat_timespec __user *, rmtp)
> {
> - struct timespec64 t64;
> - struct timespec t;
> + struct timespec64 t;
>
> switch (which_clock) {
> case CLOCK_REALTIME:
> @@ -215,16 +212,15 @@ COMPAT_SYSCALL_DEFINE4(clock_nanosleep, clockid_t, which_clock, int, flags,
> return -EINVAL;
> }
>
> - if (compat_get_timespec(&t, rqtp))
> + if (compat_get_timespec64(&t, rqtp))
> return -EFAULT;
> - t64 = timespec_to_timespec64(t);
> - if (!timespec64_valid(&t64))
> + if (!timespec64_valid(&t))
> return -EINVAL;
> if (flags & TIMER_ABSTIME)
> rmtp = NULL;
> current->restart_block.nanosleep.type = rmtp ? TT_COMPAT : TT_NONE;
> current->restart_block.nanosleep.compat_rmtp = rmtp;
> - return hrtimer_nanosleep(&t64, flags & TIMER_ABSTIME ?
> + return hrtimer_nanosleep(&t, flags & TIMER_ABSTIME ?
> HRTIMER_MODE_ABS : HRTIMER_MODE_REL,
> which_clock);
> }
> --
> 2.9.0
>
>