[PATCH v3 4/7] posix-timers: Use get_timepsec64() and put_timespec64()

From: Deepa Dinamani
Date: Sat Jun 24 2017 - 14:51:16 EST


Usage of these apis and their compat versions makes
the syscalls: clock_gettime, clock_settime, clock_getres
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>
---
kernel/time/posix-stubs.c | 83 +++++++++++++++++++++++++---------------------
kernel/time/posix-timers.c | 69 ++++++++++++++------------------------
2 files changed, 70 insertions(+), 82 deletions(-)

diff --git a/kernel/time/posix-stubs.c b/kernel/time/posix-stubs.c
index 65878221cbfb..06f34feb635e 100644
--- a/kernel/time/posix-stubs.c
+++ b/kernel/time/posix-stubs.c
@@ -51,40 +51,52 @@ SYS_NI(alarm);
SYSCALL_DEFINE2(clock_settime, const clockid_t, which_clock,
const struct timespec __user *, tp)
{
- struct timespec64 new_tp64;
- struct timespec new_tp;
+ struct timespec64 new_tp;

if (which_clock != CLOCK_REALTIME)
return -EINVAL;
- if (copy_from_user(&new_tp, tp, sizeof (*tp)))
+ if (get_timespec64(&new_tp, tp))
return -EFAULT;

- new_tp64 = timespec_to_timespec64(new_tp);
- return do_sys_settimeofday64(&new_tp64, NULL);
+ return do_sys_settimeofday64(&new_tp, NULL);
}

-SYSCALL_DEFINE2(clock_gettime, const clockid_t, which_clock,
- struct timespec __user *,tp)
+int do_clock_gettime(clockid_t which_clock, struct timespec64 *tp)
{
- struct timespec64 kernel_tp64;
- struct timespec kernel_tp;
-
switch (which_clock) {
- case CLOCK_REALTIME: ktime_get_real_ts64(&kernel_tp64); break;
- case CLOCK_MONOTONIC: ktime_get_ts64(&kernel_tp64); break;
- case CLOCK_BOOTTIME: get_monotonic_boottime64(&kernel_tp64); break;
- default: return -EINVAL;
+ case CLOCK_REALTIME:
+ ktime_get_real_ts64(tp);
+ break;
+ case CLOCK_MONOTONIC:
+ ktime_get_ts64(tp);
+ break;
+ case CLOCK_BOOTTIME:
+ get_monotonic_boottime64(tp);
+ break;
+ default:
+ return -EINVAL;
}

- kernel_tp = timespec64_to_timespec(kernel_tp64);
- if (copy_to_user(tp, &kernel_tp, sizeof (kernel_tp)))
+ return 0;
+}
+SYSCALL_DEFINE2(clock_gettime, const clockid_t, which_clock,
+ struct timespec __user *, tp)
+{
+ int ret;
+ struct timespec64 kernel_tp;
+
+ ret = do_clock_gettime(which_clock, &kernel_tp);
+ if (ret)
+ return ret;
+
+ if (put_timespec64(&kernel_tp, tp))
return -EFAULT;
return 0;
}

SYSCALL_DEFINE2(clock_getres, const clockid_t, which_clock, struct timespec __user *, tp)
{
- struct timespec rtn_tp = {
+ struct timespec64 rtn_tp = {
.tv_sec = 0,
.tv_nsec = hrtimer_resolution,
};
@@ -93,7 +105,7 @@ SYSCALL_DEFINE2(clock_getres, const clockid_t, which_clock, struct timespec __us
case CLOCK_REALTIME:
case CLOCK_MONOTONIC:
case CLOCK_BOOTTIME:
- if (copy_to_user(tp, &rtn_tp, sizeof(rtn_tp)))
+ if (put_timespec64(&rtn_tp, tp))
return -EFAULT;
return 0;
default:
@@ -142,41 +154,35 @@ COMPAT_SYS_NI(setitimer);
COMPAT_SYSCALL_DEFINE2(clock_settime, const clockid_t, which_clock,
struct compat_timespec __user *, tp)
{
- struct timespec64 new_tp64;
- struct timespec new_tp;
+ struct timespec64 new_tp;

if (which_clock != CLOCK_REALTIME)
return -EINVAL;
- if (compat_get_timespec(&new_tp, tp))
+ if (compat_get_timespec64(&new_tp, tp))
return -EFAULT;

- new_tp64 = timespec_to_timespec64(new_tp);
- return do_sys_settimeofday64(&new_tp64, NULL);
+ return do_sys_settimeofday64(&new_tp, NULL);
}

-COMPAT_SYSCALL_DEFINE2(clock_gettime, const clockid_t, which_clock,
- struct compat_timespec __user *,tp)
+COMPAT_SYSCALL_DEFINE2(clock_gettime, clockid_t, which_clock,
+ struct compat_timespec __user *, tp)
{
- struct timespec64 kernel_tp64;
- struct timespec kernel_tp;
+ int ret;
+ struct timespec64 kernel_tp;

- switch (which_clock) {
- case CLOCK_REALTIME: ktime_get_real_ts64(&kernel_tp64); break;
- case CLOCK_MONOTONIC: ktime_get_ts64(&kernel_tp64); break;
- case CLOCK_BOOTTIME: get_monotonic_boottime64(&kernel_tp64); break;
- default: return -EINVAL;
- }
+ ret = do_clock_gettime(which_clock, &kernel_tp);
+ if (ret)
+ return ret;

- kernel_tp = timespec64_to_timespec(kernel_tp64);
- if (compat_put_timespec(&kernel_tp, tp))
+ if (compat_put_timespec64(&kernel_tp, tp))
return -EFAULT;
return 0;
}

-COMPAT_SYSCALL_DEFINE2(clock_getres, const clockid_t, which_clock,
+COMPAT_SYSCALL_DEFINE2(clock_getres, clockid_t, which_clock,
struct compat_timespec __user *, tp)
{
- struct timespec rtn_tp = {
+ struct timespec64 rtn_tp = {
.tv_sec = 0,
.tv_nsec = hrtimer_resolution,
};
@@ -185,13 +191,14 @@ COMPAT_SYSCALL_DEFINE2(clock_getres, const clockid_t, which_clock,
case CLOCK_REALTIME:
case CLOCK_MONOTONIC:
case CLOCK_BOOTTIME:
- if (compat_put_timespec(&rtn_tp, tp))
+ if (compat_put_timespec64(&rtn_tp, tp))
return -EFAULT;
return 0;
default:
return -EINVAL;
}
}
+
COMPAT_SYSCALL_DEFINE4(clock_nanosleep, clockid_t, which_clock, int, flags,
struct compat_timespec __user *, rqtp,
struct compat_timespec __user *, rmtp)
diff --git a/kernel/time/posix-timers.c b/kernel/time/posix-timers.c
index 82d67be7d9d1..8717f4bc7182 100644
--- a/kernel/time/posix-timers.c
+++ b/kernel/time/posix-timers.c
@@ -1049,34 +1049,30 @@ SYSCALL_DEFINE2(clock_settime, const clockid_t, which_clock,
const struct timespec __user *, tp)
{
const struct k_clock *kc = clockid_to_kclock(which_clock);
- struct timespec64 new_tp64;
- struct timespec new_tp;
+ struct timespec64 new_tp;

if (!kc || !kc->clock_set)
return -EINVAL;

- if (copy_from_user(&new_tp, tp, sizeof (*tp)))
+ if (get_timespec64(&new_tp, tp))
return -EFAULT;
- new_tp64 = timespec_to_timespec64(new_tp);

- return kc->clock_set(which_clock, &new_tp64);
+ return kc->clock_set(which_clock, &new_tp);
}

SYSCALL_DEFINE2(clock_gettime, const clockid_t, which_clock,
struct timespec __user *,tp)
{
const struct k_clock *kc = clockid_to_kclock(which_clock);
- struct timespec64 kernel_tp64;
- struct timespec kernel_tp;
+ struct timespec64 kernel_tp;
int error;

if (!kc)
return -EINVAL;

- error = kc->clock_get(which_clock, &kernel_tp64);
- kernel_tp = timespec64_to_timespec(kernel_tp64);
+ error = kc->clock_get(which_clock, &kernel_tp);

- if (!error && copy_to_user(tp, &kernel_tp, sizeof (kernel_tp)))
+ if (!error && put_timespec64(&kernel_tp, tp))
error = -EFAULT;

return error;
@@ -1109,17 +1105,15 @@ SYSCALL_DEFINE2(clock_getres, const clockid_t, which_clock,
struct timespec __user *, tp)
{
const struct k_clock *kc = clockid_to_kclock(which_clock);
- struct timespec64 rtn_tp64;
- struct timespec rtn_tp;
+ struct timespec64 rtn_tp;
int error;

if (!kc)
return -EINVAL;

- error = kc->clock_getres(which_clock, &rtn_tp64);
- rtn_tp = timespec64_to_timespec(rtn_tp64);
+ error = kc->clock_getres(which_clock, &rtn_tp);

- if (!error && tp && copy_to_user(tp, &rtn_tp, sizeof (rtn_tp)))
+ if (!error && tp && put_timespec64(&rtn_tp, tp))
error = -EFAULT;

return error;
@@ -1131,38 +1125,30 @@ COMPAT_SYSCALL_DEFINE2(clock_settime, clockid_t, which_clock,
struct compat_timespec __user *, tp)
{
const struct k_clock *kc = clockid_to_kclock(which_clock);
- struct timespec64 new_tp64;
- struct timespec new_tp;
+ struct timespec64 ts;

- if (!kc || !kc->clock_set)
- return -EINVAL;
-
- if (compat_get_timespec(&new_tp, tp))
+ if (compat_get_timespec64(&ts, tp))
return -EFAULT;

- new_tp64 = timespec_to_timespec64(new_tp);
-
- return kc->clock_set(which_clock, &new_tp64);
+ return kc->clock_set(which_clock, &ts);
}

COMPAT_SYSCALL_DEFINE2(clock_gettime, clockid_t, which_clock,
struct compat_timespec __user *, tp)
{
const struct k_clock *kc = clockid_to_kclock(which_clock);
- struct timespec64 kernel_tp64;
- struct timespec kernel_tp;
- int error;
+ struct timespec64 ts;
+ int err;

if (!kc)
return -EINVAL;

- error = kc->clock_get(which_clock, &kernel_tp64);
- kernel_tp = timespec64_to_timespec(kernel_tp64);
+ err = kc->clock_get(which_clock, &ts);

- if (!error && compat_put_timespec(&kernel_tp, tp))
- error = -EFAULT;
+ if (!err && compat_put_timespec64(&ts, tp))
+ err = -EFAULT;

- return error;
+ return err;
}

COMPAT_SYSCALL_DEFINE2(clock_adjtime, clockid_t, which_clock,
@@ -1193,21 +1179,16 @@ COMPAT_SYSCALL_DEFINE2(clock_getres, clockid_t, which_clock,
struct compat_timespec __user *, tp)
{
const struct k_clock *kc = clockid_to_kclock(which_clock);
- struct timespec64 rtn_tp64;
- struct timespec rtn_tp;
- int error;
-
- if (!kc)
- return -EINVAL;
-
- error = kc->clock_getres(which_clock, &rtn_tp64);
- rtn_tp = timespec64_to_timespec(rtn_tp64);
+ struct timespec64 ts;
+ int err;

- if (!error && tp && compat_put_timespec(&rtn_tp, tp))
- error = -EFAULT;
+ err = kc->clock_getres(which_clock, &ts);
+ if (!err && tp && compat_put_timespec64(&ts, tp))
+ return -EFAULT;

- return error;
+ return err;
}
+
#endif

/*
--
2.11.0