diff options
| author | Ondrej Mosnacek <omosnace@redhat.com> | 2019-04-10 11:14:19 +0200 |
|---|---|---|
| committer | Paul Moore <paul@paul-moore.com> | 2019-04-15 18:10:17 -0400 |
| commit | 2d87a0674bd60d855e4008e2d84f5b23d7cb9b7d (patch) | |
| tree | f1652a306b9313539536d13ab52aa94249d1b0c9 /kernel | |
| parent | 699c1868a743f530081f429058616a2dd5d8a4b2 (diff) | |
timekeeping: Audit clock adjustments
Emit an audit record whenever the system clock is changed (i.e. shifted
by a non-zero offset) by a syscall from userspace. The syscalls than can
(at the time of writing) trigger such record are:
- settimeofday(2), stime(2), clock_settime(2) -- via
do_settimeofday64()
- adjtimex(2), clock_adjtime(2) -- via do_adjtimex()
The new records have type AUDIT_TIME_INJOFFSET and contain the following
fields:
- sec -- the 'seconds' part of the offset
- nsec -- the 'nanoseconds' part of the offset
Example record (time was shifted backwards by ~15.875 seconds):
type=TIME_INJOFFSET msg=audit(1530616049.652:13): sec=-16 nsec=124887145
The records of this type will be associated with the corresponding
syscall records.
Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Reviewed-by: Richard Guy Briggs <rgb@redhat.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
[PM: fixed a line width problem in __audit_tk_injoffset()]
Signed-off-by: Paul Moore <paul@paul-moore.com>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/auditsc.c | 7 | ||||
| -rw-r--r-- | kernel/time/timekeeping.c | 6 |
2 files changed, 13 insertions, 0 deletions
diff --git a/kernel/auditsc.c b/kernel/auditsc.c index 51a2ceb3a1ca..3843495d0083 100644 --- a/kernel/auditsc.c +++ b/kernel/auditsc.c @@ -2512,6 +2512,13 @@ void __audit_fanotify(unsigned int response) AUDIT_FANOTIFY, "resp=%u", response); } +void __audit_tk_injoffset(struct timespec64 offset) +{ + audit_log(audit_context(), GFP_KERNEL, AUDIT_TIME_INJOFFSET, + "sec=%lli nsec=%li", + (long long)offset.tv_sec, offset.tv_nsec); +} + static void audit_log_task(struct audit_buffer *ab) { kuid_t auid, uid; diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index f986e1918d12..3d24be4cd607 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -21,6 +21,7 @@ #include <linux/stop_machine.h> #include <linux/pvclock_gtod.h> #include <linux/compiler.h> +#include <linux/audit.h> #include "tick-internal.h" #include "ntp_internal.h" @@ -1250,6 +1251,9 @@ out: /* signal hrtimers about time change */ clock_was_set(); + if (!ret) + audit_tk_injoffset(ts_delta); + return ret; } EXPORT_SYMBOL(do_settimeofday64); @@ -2322,6 +2326,8 @@ int do_adjtimex(struct __kernel_timex *txc) ret = timekeeping_inject_offset(&delta); if (ret) return ret; + + audit_tk_injoffset(delta); } ktime_get_real_ts64(&ts); |