From 021dd87bc055a5bfb2dcef83fc868fe24648b959 Mon Sep 17 00:00:00 2001 From: Lennart Poettering Date: Wed, 3 Feb 2016 18:28:40 +0100 Subject: resolved: apply epoch to system time from PID 1 For use in timesyncd we already defined a compile-time "epoch" value, which is based on the mtime of the NEWS file, and specifies a point in time we know lies in the past at runtime. timesyncd uses this to filter out nonsensical timestamp file data, and bump the system clock to a time that is after the build time of systemd. This patch adds similar bumping code to earliest PID 1 initialization, so that the system never continues operation with a clock that is in the 1970ies or even 1930s. --- src/basic/clock-util.c | 14 ++++++++++++++ src/basic/clock-util.h | 1 + 2 files changed, 15 insertions(+) (limited to 'src/basic') diff --git a/src/basic/clock-util.c b/src/basic/clock-util.c index 05788a360e..c64b2e5e8c 100644 --- a/src/basic/clock-util.c +++ b/src/basic/clock-util.c @@ -146,3 +146,17 @@ int clock_reset_timewarp(void) { return 0; } + +#define TIME_EPOCH_USEC ((usec_t) TIME_EPOCH * USEC_PER_SEC) + +int clock_apply_epoch(void) { + struct timespec ts; + + if (now(CLOCK_REALTIME) >= TIME_EPOCH_USEC) + return 0; + + if (clock_settime(CLOCK_REALTIME, timespec_store(&ts, TIME_EPOCH_USEC)) < 0) + return -errno; + + return 1; +} diff --git a/src/basic/clock-util.h b/src/basic/clock-util.h index fef2d471a6..09d46758f4 100644 --- a/src/basic/clock-util.h +++ b/src/basic/clock-util.h @@ -28,3 +28,4 @@ int clock_set_timezone(int *min); int clock_reset_timewarp(void); int clock_get_hwclock(struct tm *tm); int clock_set_hwclock(const struct tm *tm); +int clock_apply_epoch(void); -- cgit v1.2.3-54-g00ecf