[patch 13/20] posix-timers: Document sys_clock_settime() permissions in place

From: Thomas Gleixner
Date: Tue Apr 25 2023 - 14:50:02 EST


The documentation of sys_clock_settime() permissions is at a random place
and mostly word salad.

Remove it and add a concise comment into sys_clock_settime().

Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
---
kernel/time/posix-timers.c | 11 ++++-------
1 file changed, 4 insertions(+), 7 deletions(-)

--- a/kernel/time/posix-timers.c
+++ b/kernel/time/posix-timers.c
@@ -74,13 +74,6 @@ static const struct k_clock clock_realti
* following: 1.) The k_itimer struct (sched.h) is used for
* the timer. 2.) The list, it_lock, it_clock, it_id and
* it_pid fields are not modified by timer code.
- *
- * Permissions: It is assumed that the clock_settime() function defined
- * for each clock will take care of permission checks. Some
- * clocks may be set able by any user (i.e. local process
- * clocks) others not. Currently the only set able clock we
- * have is CLOCK_REALTIME and its high res counter part, both of
- * which we beg off on and pass to do_sys_settimeofday().
*/
static struct k_itimer *__lock_timer(timer_t timer_id, unsigned long *flags);

@@ -1165,6 +1158,10 @@ SYSCALL_DEFINE2(clock_settime, const clo
if (get_timespec64(&new_tp, tp))
return -EFAULT;

+ /*
+ * Permission checks have to be done inside the clock specific
+ * setter callback.
+ */
return kc->clock_set(which_clock, &new_tp);
}