[PATCH v3 5/7] nanosleep: Use get_timepsec64() and put_timespec64()

From: Deepa Dinamani
Date: Sat Jun 24 2017 - 14:51:13 EST

Usage of these apis and their compat versions makes
the syscalls: clock_nanosleep and nanosleep and
their compat implementations simpler.

This is a preparatory patch to isolate data conversions to
struct timespec64 at userspace boundaries. This helps contain
the changes needed to transition to new y2038 safe types.

Signed-off-by: Deepa Dinamani <deepa.kernel@xxxxxxxxx>
---
include/linux/hrtimer.h | 2 +-
kernel/time/alarmtimer.c | 4 ++--
kernel/time/hrtimer.c | 30 +++++++++++++-----------------
kernel/time/posix-cpu-timers.c | 8 ++------
kernel/time/posix-timers.c | 20 ++++++++------------
5 files changed, 26 insertions(+), 38 deletions(-)

diff --git a/include/linux/hrtimer.h b/include/linux/hrtimer.h
index 255edd5e7a74..012c37fdb688 100644
--- a/include/linux/hrtimer.h
+++ b/include/linux/hrtimer.h
@@ -453,7 +453,7 @@ static inline u64 hrtimer_forward_now(struct hrtimer *timer,

/* Precise sleep: */

-extern int nanosleep_copyout(struct restart_block *, struct timespec *);
+extern int nanosleep_copyout(struct restart_block *, struct timespec64 *);
extern long hrtimer_nanosleep(const struct timespec64 *rqtp,
const enum hrtimer_mode mode,
const clockid_t clockid);
diff --git a/kernel/time/alarmtimer.c b/kernel/time/alarmtimer.c
index c991cf212c6d..0b8ff7d257ea 100644
--- a/kernel/time/alarmtimer.c
+++ b/kernel/time/alarmtimer.c
@@ -712,14 +712,14 @@ static int alarmtimer_do_nsleep(struct alarm *alarm, ktime_t absexp,
alarmtimer_freezerset(absexp, type);
restart = &current->restart_block;
if (restart->nanosleep.type != TT_NONE) {
- struct timespec rmt;
+ struct timespec64 rmt;
ktime_t rem;

rem = ktime_sub(absexp, alarm_bases[type].gettime());

if (rem <= 0)
return 0;
- rmt = ktime_to_timespec(rem);
+ rmt = ktime_to_timespec64(rem);

return nanosleep_copyout(restart, &rmt);
}
diff --git a/kernel/time/hrtimer.c b/kernel/time/hrtimer.c
index 81da124f1115..88f75f92ef36 100644
--- a/kernel/time/hrtimer.c
+++ b/kernel/time/hrtimer.c
@@ -1440,17 +1440,17 @@ void hrtimer_init_sleeper(struct hrtimer_sleeper *sl, struct task_struct *task)
}
EXPORT_SYMBOL_GPL(hrtimer_init_sleeper);

-int nanosleep_copyout(struct restart_block *restart, struct timespec *ts)
+int nanosleep_copyout(struct restart_block *restart, struct timespec64 *ts)
{
switch(restart->nanosleep.type) {
#ifdef CONFIG_COMPAT
case TT_COMPAT:
- if (compat_put_timespec(ts, restart->nanosleep.compat_rmtp))
+ if (compat_put_timespec64(ts, restart->nanosleep.compat_rmtp))
return -EFAULT;
break;
#endif
case TT_NATIVE:
- if (copy_to_user(restart->nanosleep.rmtp, ts, sizeof(struct timespec)))
+ if (put_timespec64(ts, restart->nanosleep.rmtp))
return -EFAULT;
break;
default:
@@ -1485,11 +1485,11 @@ static int __sched do_nanosleep(struct hrtimer_sleeper *t, enum hrtimer_mode mod
restart = &current->restart_block;
if (restart->nanosleep.type != TT_NONE) {
ktime_t rem = hrtimer_expires_remaining(&t->timer);
- struct timespec rmt;
+ struct timespec64 rmt;

if (rem <= 0)
return 0;
- rmt = ktime_to_timespec(rem);
+ rmt = ktime_to_timespec64(rem);

return nanosleep_copyout(restart, &rmt);
}
@@ -1546,19 +1546,17 @@ long hrtimer_nanosleep(const struct timespec64 *rqtp,
SYSCALL_DEFINE2(nanosleep, struct timespec __user *, rqtp,
struct timespec __user *, rmtp)
{
- struct timespec64 tu64;
- struct timespec tu;
+ struct timespec64 tu;

- if (copy_from_user(&tu, rqtp, sizeof(tu)))
+ if (get_timespec64(&tu, rqtp))
return -EFAULT;

- tu64 = timespec_to_timespec64(tu);
- if (!timespec64_valid(&tu64))
+ if (!timespec64_valid(&tu))
return -EINVAL;

current->restart_block.nanosleep.type = rmtp ? TT_NATIVE : TT_NONE;
current->restart_block.nanosleep.rmtp = rmtp;
- return hrtimer_nanosleep(&tu64, HRTIMER_MODE_REL, CLOCK_MONOTONIC);
+ return hrtimer_nanosleep(&tu, HRTIMER_MODE_REL, CLOCK_MONOTONIC);
}

#ifdef CONFIG_COMPAT
@@ -1566,19 +1564,17 @@ SYSCALL_DEFINE2(nanosleep, struct timespec __user *, rqtp,
COMPAT_SYSCALL_DEFINE2(nanosleep, struct compat_timespec __user *, rqtp,
struct compat_timespec __user *, rmtp)
{
- struct timespec64 tu64;
- struct timespec tu;
+ struct timespec64 tu;

- if (compat_get_timespec(&tu, rqtp))
+ if (compat_get_timespec64(&tu, rqtp))
return -EFAULT;

- tu64 = timespec_to_timespec64(tu);
- if (!timespec64_valid(&tu64))
+ if (!timespec64_valid(&tu))
return -EINVAL;

current->restart_block.nanosleep.type = rmtp ? TT_COMPAT : TT_NONE;
current->restart_block.nanosleep.compat_rmtp = rmtp;
- return hrtimer_nanosleep(&tu64, HRTIMER_MODE_REL, CLOCK_MONOTONIC);
+ return hrtimer_nanosleep(&tu, HRTIMER_MODE_REL, CLOCK_MONOTONIC);
}
#endif

diff --git a/kernel/time/posix-cpu-timers.c b/kernel/time/posix-cpu-timers.c
index 60cb24ac9ebc..a3bd5dbe0dc4 100644
--- a/kernel/time/posix-cpu-timers.c
+++ b/kernel/time/posix-cpu-timers.c
@@ -1318,12 +1318,8 @@ static int do_cpu_nanosleep(const clockid_t which_clock, int flags,
*/
restart = &current->restart_block;
restart->nanosleep.expires = expires;
- if (restart->nanosleep.type != TT_NONE) {
- struct timespec ts;
-
- ts = timespec64_to_timespec(it.it_value);
- error = nanosleep_copyout(restart, &ts);
- }
+ if (restart->nanosleep.type != TT_NONE)
+ error = nanosleep_copyout(restart, &it.it_value);
}

return error;
diff --git a/kernel/time/posix-timers.c b/kernel/time/posix-timers.c
index 8717f4bc7182..6818818caffd 100644
--- a/kernel/time/posix-timers.c
+++ b/kernel/time/posix-timers.c
@@ -1207,26 +1207,24 @@ SYSCALL_DEFINE4(clock_nanosleep, const clockid_t, which_clock, int, flags,
struct timespec __user *, rmtp)
{
const struct k_clock *kc = clockid_to_kclock(which_clock);
- struct timespec64 t64;
- struct timespec t;
+ struct timespec64 t;

if (!kc)
return -EINVAL;
if (!kc->nsleep)
return -ENANOSLEEP_NOTSUP;

- 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 kc->nsleep(which_clock, flags, &t64);
+ return kc->nsleep(which_clock, flags, &t);
}

#ifdef CONFIG_COMPAT
@@ -1235,26 +1233,24 @@ COMPAT_SYSCALL_DEFINE4(clock_nanosleep, clockid_t, which_clock, int, flags,
struct compat_timespec __user *, rmtp)
{
const struct k_clock *kc = clockid_to_kclock(which_clock);
- struct timespec64 t64;
- struct timespec t;
+ struct timespec64 t;

if (!kc)
return -EINVAL;
if (!kc->nsleep)
return -ENANOSLEEP_NOTSUP;

- 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 kc->nsleep(which_clock, flags, &t64);
+ return kc->nsleep(which_clock, flags, &t);
}
#endif

--
2.11.0