linux/kernel/time
Ondrej Mosnacek 7e8eda734d ntp: Audit NTP parameters adjustment
Emit an audit record every time selected NTP parameters are modified
from userspace (via adjtimex(2) or clock_adjtime(2)). These parameters
may be used to indirectly change system clock, and thus their
modifications should be audited.

Such events will now generate records of type AUDIT_TIME_ADJNTPVAL
containing the following fields:
  - op -- which value was adjusted:
    - offset -- corresponding to the time_offset variable
    - freq   -- corresponding to the time_freq variable
    - status -- corresponding to the time_status variable
    - adjust -- corresponding to the time_adjust variable
    - tick   -- corresponding to the tick_usec variable
    - tai    -- corresponding to the timekeeping's TAI offset
  - old -- the old value
  - new -- the new value

Example records:

type=TIME_ADJNTPVAL msg=audit(1530616044.507:7): op=status old=64 new=8256
type=TIME_ADJNTPVAL msg=audit(1530616044.511:11): op=freq old=0 new=49180377088000

The records of this type will be associated with the corresponding
syscall records.

An overview of parameter changes that can be done via do_adjtimex()
(based on information from Miroslav Lichvar) and whether they are
audited:
  __timekeeping_set_tai_offset() -- sets the offset from the
                                    International Atomic Time
                                    (AUDITED)
  NTP variables:
    time_offset -- can adjust the clock by up to 0.5 seconds per call
                   and also speed it up or slow down by up to about
                   0.05% (43 seconds per day) (AUDITED)
    time_freq -- can speed up or slow down by up to about 0.05%
                 (AUDITED)
    time_status -- can insert/delete leap seconds and it also enables/
                   disables synchronization of the hardware real-time
                   clock (AUDITED)
    time_maxerror, time_esterror -- change error estimates used to
                                    inform userspace applications
                                    (NOT AUDITED)
    time_constant -- controls the speed of the clock adjustments that
                     are made when time_offset is set (NOT AUDITED)
    time_adjust -- can temporarily speed up or slow down the clock by up
                   to 0.05% (AUDITED)
    tick_usec -- a more extreme version of time_freq; can speed up or
                 slow down the clock by up to 10% (AUDITED)

Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Reviewed-by: Richard Guy Briggs <rgb@redhat.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2019-04-15 18:14:01 -04:00
..
alarmtimer.c time: Remove license boilerplate 2018-11-23 11:51:21 +01:00
clockevents.c hrtimers/tick/clockevents: Remove sloppy license references 2018-11-23 11:51:21 +01:00
clocksource.c time: Remove license boilerplate 2018-11-23 11:51:21 +01:00
hrtimer.c Merge branch 'timers-2038-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2019-03-05 14:08:26 -08:00
itimer.c time: Remove useless filenames in top level comments 2018-11-23 11:51:20 +01:00
jiffies.c time: Remove license boilerplate 2018-11-23 11:51:21 +01:00
Kconfig time: Move CONTEXT_TRACKING to kernel/time/Kconfig 2019-01-15 11:16:41 +01:00
Makefile License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
ntp_internal.h ntp: Audit NTP parameters adjustment 2019-04-15 18:14:01 -04:00
ntp.c ntp: Audit NTP parameters adjustment 2019-04-15 18:14:01 -04:00
posix-clock.c timex: use __kernel_timex internally 2019-02-07 00:13:27 +01:00
posix-cpu-timers.c posix-cpu-timers: Remove private interval storage 2019-01-15 16:36:13 +01:00
posix-stubs.c y2038: syscalls: rename y2038 compat syscalls 2019-02-07 00:13:27 +01:00
posix-timers.c y2038: syscalls: rename y2038 compat syscalls 2019-02-07 00:13:27 +01:00
posix-timers.h timex: use __kernel_timex internally 2019-02-07 00:13:27 +01:00
sched_clock.c sched/clock: Remove license boilerplate 2018-11-23 11:51:22 +01:00
test_udelay.c time/debug: Remove license boilerplate 2018-11-23 11:51:21 +01:00
tick-broadcast-hrtimer.c time: Remove useless filenames in top level comments 2018-11-23 11:51:20 +01:00
tick-broadcast.c timers: Mark expected switch fall-throughs 2019-01-29 20:08:42 +01:00
tick-common.c hrtimers/tick/clockevents: Remove sloppy license references 2018-11-23 11:51:21 +01:00
tick-internal.h Revert: Unify CLOCK_MONOTONIC and CLOCK_BOOTTIME 2018-04-26 14:53:32 +02:00
tick-oneshot.c hrtimers/tick/clockevents: Remove sloppy license references 2018-11-23 11:51:21 +01:00
tick-sched.c hrtimers/tick/clockevents: Remove sloppy license references 2018-11-23 11:51:21 +01:00
tick-sched.h nohz: Gather tick_sched booleans under a common flag field 2018-04-09 11:54:57 +02:00
time.c y2038: rename old time and utime syscalls 2019-02-07 00:13:28 +01:00
timeconst.bc time: Add SPDX license identifiers 2018-11-23 11:51:20 +01:00
timeconv.c time: Add SPDX license identifiers 2018-11-23 11:51:20 +01:00
timecounter.c time: Remove license boilerplate 2018-11-23 11:51:21 +01:00
timekeeping_debug.c timekeeping/debug: No need to check return value of debugfs_create functions 2019-01-29 20:08:41 +01:00
timekeeping_internal.h timekeeping/ntp: Constify some function arguments 2018-07-19 17:08:05 -07:00
timekeeping.c ntp: Audit NTP parameters adjustment 2019-04-15 18:14:01 -04:00
timekeeping.h Revert: Unify CLOCK_MONOTONIC and CLOCK_BOOTTIME 2018-04-26 14:53:32 +02:00
timer_list.c hrtimers/tick/clockevents: Remove sloppy license references 2018-11-23 11:51:21 +01:00
timer.c Merge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2019-03-05 14:49:11 -08:00