posix-timers: Make clock_nanosleep() time namespace aware

clock_nanosleep() accepts absolute values of expiration time, if the
TIMER_ABSTIME flag is set. This value is in the tasks time namespace,
which has to be converted to the host time namespace.

Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Andrei Vagin <avagin@openvz.org>
Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20191112012724.250792-18-dima@arista.com

diff --git a/kernel/time/posix-stubs.c b/kernel/time/posix-stubs.c
index 5745a13..fcb3b21 100644 (file)
--- a/kernel/time/posix-stubs.c
+++ b/kernel/time/posix-stubs.c
@@ -129,6 +129,7 @@ SYSCALL_DEFINE4(clock_nanosleep, const clockid_t, which_clock, int, flags,
                struct __kernel_timespec __user *, rmtp)
 {
        struct timespec64 t;
+       ktime_t texp;
 
        switch (which_clock) {
        case CLOCK_REALTIME:
@@ -147,7 +148,10 @@ SYSCALL_DEFINE4(clock_nanosleep, const clockid_t, which_clock, int, flags,
                rmtp = NULL;
        current->restart_block.nanosleep.type = rmtp ? TT_NATIVE : TT_NONE;
        current->restart_block.nanosleep.rmtp = rmtp;
-       return hrtimer_nanosleep(timespec64_to_ktime(t), flags & TIMER_ABSTIME ?
+       texp = timespec64_to_ktime(t);
+       if (flags & TIMER_ABSTIME)
+               texp = timens_ktime_to_host(which_clock, texp);
+       return hrtimer_nanosleep(texp, flags & TIMER_ABSTIME ?
                                 HRTIMER_MODE_ABS : HRTIMER_MODE_REL,
                                 which_clock);
 }
@@ -218,6 +222,7 @@ SYSCALL_DEFINE4(clock_nanosleep_time32, clockid_t, which_clock, int, flags,
                struct old_timespec32 __user *, rmtp)
 {
        struct timespec64 t;
+       ktime_t texp;
 
        switch (which_clock) {
        case CLOCK_REALTIME:
@@ -236,7 +241,10 @@ SYSCALL_DEFINE4(clock_nanosleep_time32, clockid_t, which_clock, int, flags,
                rmtp = NULL;
        current->restart_block.nanosleep.type = rmtp ? TT_COMPAT : TT_NONE;
        current->restart_block.nanosleep.compat_rmtp = rmtp;
-       return hrtimer_nanosleep(timespec64_to_ktime(t), flags & TIMER_ABSTIME ?
+       texp = timespec64_to_ktime(t);
+       if (flags & TIMER_ABSTIME)
+               texp = timens_ktime_to_host(which_clock, texp);
+       return hrtimer_nanosleep(texp, flags & TIMER_ABSTIME ?
                                 HRTIMER_MODE_ABS : HRTIMER_MODE_REL,
                                 which_clock);
 }

diff --git a/kernel/time/posix-timers.c b/kernel/time/posix-timers.c
index 75fee6e..ff0eb30 100644 (file)
--- a/kernel/time/posix-timers.c
+++ b/kernel/time/posix-timers.c
@@ -1228,6 +1228,19 @@ static int common_nsleep(const clockid_t which_clock, int flags,
                                 which_clock);
 }
 
+static int common_nsleep_timens(const clockid_t which_clock, int flags,
+                        const struct timespec64 *rqtp)
+{
+       ktime_t texp = timespec64_to_ktime(*rqtp);
+
+       if (flags & TIMER_ABSTIME)
+               texp = timens_ktime_to_host(which_clock, texp);
+
+       return hrtimer_nanosleep(texp, flags & TIMER_ABSTIME ?
+                                HRTIMER_MODE_ABS : HRTIMER_MODE_REL,
+                                which_clock);
+}
+
 SYSCALL_DEFINE4(clock_nanosleep, const clockid_t, which_clock, int, flags,
                const struct __kernel_timespec __user *, rqtp,
                struct __kernel_timespec __user *, rmtp)
@@ -1305,7 +1318,7 @@ static const struct k_clock clock_monotonic = {
        .clock_getres           = posix_get_hrtimer_res,
        .clock_get_timespec     = posix_get_monotonic_timespec,
        .clock_get_ktime        = posix_get_monotonic_ktime,
-       .nsleep                 = common_nsleep,
+       .nsleep                 = common_nsleep_timens,
        .timer_create           = common_timer_create,
        .timer_set              = common_timer_set,
        .timer_get              = common_timer_get,
@@ -1354,7 +1367,7 @@ static const struct k_clock clock_boottime = {
        .clock_getres           = posix_get_hrtimer_res,
        .clock_get_ktime        = posix_get_boottime_ktime,
        .clock_get_timespec     = posix_get_boottime_timespec,
-       .nsleep                 = common_nsleep,
+       .nsleep                 = common_nsleep_timens,
        .timer_create           = common_timer_create,
        .timer_set              = common_timer_set,
        .timer_get              = common_timer_get,