1 files changed, 64 insertions, 42 deletions

diff --git a/kernel/time/hrtimer.c b/kernel/time/hrtimer.c
index ac053bb5296e..81da124f1115 100644
--- a/kernel/time/hrtimer.c
+++ b/kernel/time/hrtimer.c
@@ -51,6 +51,7 @@
 #include <linux/sched/debug.h>
 #include <linux/timer.h>
 #include <linux/freezer.h>
+#include <linux/compat.h>
 
 #include <linux/uaccess.h>
 
@@ -1439,8 +1440,29 @@ 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)
+{
+        switch(restart->nanosleep.type) {
+#ifdef CONFIG_COMPAT
+        case TT_COMPAT:
+                if (compat_put_timespec(ts, restart->nanosleep.compat_rmtp))
+                        return -EFAULT;
+                break;
+#endif
+        case TT_NATIVE:
+                if (copy_to_user(restart->nanosleep.rmtp, ts, sizeof(struct timespec)))
+                        return -EFAULT;
+                break;
+        default:
+                BUG();
+        }
+        return -ERESTART_RESTARTBLOCK;
+}
+
 static int __sched do_nanosleep(struct hrtimer_sleeper *t, enum hrtimer_mode mode)
 {
+        struct restart_block *restart;
+
         hrtimer_init_sleeper(t, current);
 
         do {
@@ -1457,53 +1479,38 @@ static int __sched do_nanosleep(struct hrtimer_sleeper *t, enum hrtimer_mode mod
 
         __set_current_state(TASK_RUNNING);
 
-        return t->task == NULL;
-}
-
-static int update_rmtp(struct hrtimer *timer, struct timespec __user *rmtp)
-{
-        struct timespec rmt;
-        ktime_t rem;
-
-        rem = hrtimer_expires_remaining(timer);
-        if (rem <= 0)
+        if (!t->task)
                 return 0;
-        rmt = ktime_to_timespec(rem);
 
-        if (copy_to_user(rmtp, &rmt, sizeof(*rmtp)))
-                return -EFAULT;
+        restart = &current->restart_block;
+        if (restart->nanosleep.type != TT_NONE) {
+                ktime_t rem = hrtimer_expires_remaining(&t->timer);
+                struct timespec rmt;
 
-        return 1;
+                if (rem <= 0)
+                        return 0;
+                rmt = ktime_to_timespec(rem);
+
+                return nanosleep_copyout(restart, &rmt);
+        }
+        return -ERESTART_RESTARTBLOCK;
 }
 
-long __sched hrtimer_nanosleep_restart(struct restart_block *restart)
+static long __sched hrtimer_nanosleep_restart(struct restart_block *restart)
 {
         struct hrtimer_sleeper t;
-        struct timespec __user  *rmtp;
-        int ret = 0;
+        int ret;
 
         hrtimer_init_on_stack(&t.timer, restart->nanosleep.clockid,
                                 HRTIMER_MODE_ABS);
         hrtimer_set_expires_tv64(&t.timer, restart->nanosleep.expires);
 
-        if (do_nanosleep(&t, HRTIMER_MODE_ABS))
-                goto out;
-
-        rmtp = restart->nanosleep.rmtp;
-        if (rmtp) {
-                ret = update_rmtp(&t.timer, rmtp);
-                if (ret <= 0)
-                        goto out;
-        }
-
-        /* The other values in restart are already filled in */
-        ret = -ERESTART_RESTARTBLOCK;
-out:
+        ret = do_nanosleep(&t, HRTIMER_MODE_ABS);
         destroy_hrtimer_on_stack(&t.timer);
         return ret;
 }
 
-long hrtimer_nanosleep(struct timespec64 *rqtp, struct timespec __user *rmtp,
+long hrtimer_nanosleep(const struct timespec64 *rqtp,
                        const enum hrtimer_mode mode, const clockid_t clockid)
 {
         struct restart_block *restart;
@@ -1517,7 +1524,8 @@ long hrtimer_nanosleep(struct timespec64 *rqtp, struct timespec __user *rmtp,
 
         hrtimer_init_on_stack(&t.timer, clockid, mode);
         hrtimer_set_expires_range_ns(&t.timer, timespec64_to_ktime(*rqtp), slack);
-        if (do_nanosleep(&t, mode))
+        ret = do_nanosleep(&t, mode);
+        if (ret != -ERESTART_RESTARTBLOCK)
                 goto out;
 
         /* Absolute timers do not update the rmtp value and restart: */
@@ -1526,19 +1534,10 @@ long hrtimer_nanosleep(struct timespec64 *rqtp, struct timespec __user *rmtp,
                 goto out;
         }
 
-        if (rmtp) {
-                ret = update_rmtp(&t.timer, rmtp);
-                if (ret <= 0)
-                        goto out;
-        }
-
         restart = &current->restart_block;
         restart->fn = hrtimer_nanosleep_restart;
         restart->nanosleep.clockid = t.timer.base->clockid;
-        restart->nanosleep.rmtp = rmtp;
         restart->nanosleep.expires = hrtimer_get_expires_tv64(&t.timer);
-
-        ret = -ERESTART_RESTARTBLOCK;
 out:
         destroy_hrtimer_on_stack(&t.timer);
         return ret;
@@ -1557,8 +1556,31 @@ SYSCALL_DEFINE2(nanosleep, struct timespec __user *, rqtp,
         if (!timespec64_valid(&tu64))
                 return -EINVAL;
 
-        return hrtimer_nanosleep(&tu64, rmtp, HRTIMER_MODE_REL, CLOCK_MONOTONIC);
+        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);
+}
+
+#ifdef CONFIG_COMPAT
+
+COMPAT_SYSCALL_DEFINE2(nanosleep, struct compat_timespec __user *, rqtp,
+                       struct compat_timespec __user *, rmtp)
+{
+        struct timespec64 tu64;
+        struct timespec tu;
+
+        if (compat_get_timespec(&tu, rqtp))
+                return -EFAULT;
+
+        tu64 = timespec_to_timespec64(tu);
+        if (!timespec64_valid(&tu64))
+                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);
 }
+#endif
 
 /*
  * Functions related to boot-time initialization: