posix-timers: Fix clock_adjtime to always return timex data on success

The clock_adj call returns the clock state on success, which may be a
non-zero value (e.g. TIME_INS), but the modified timex data is copied
back to the user only when zero value (TIME_OK) was returned. Fix the
condition to copy the data also with positive return values.
Signed-off-by: NMiroslav Lichvar <mlichvar@redhat.com>
Signed-off-by: NJohn Stultz <john.stultz@linaro.org>

kernel/posix-timers.c

@@ -997,7 +997,7 @@ SYSCALL_DEFINE2(clock_adjtime, const clockid_t, which_clock,
 
 	err = kc->clock_adj(which_clock, &ktx);
 
-	if (!err && copy_to_user(utx, &ktx, sizeof(ktx)))
+	if (err >= 0 && copy_to_user(utx, &ktx, sizeof(ktx)))
 		return -EFAULT;
 
 	return err;