The code to check the adjtimex() or clock_adjtime() arguments is spread
out across multiple files for presumably only historic reasons. As a
preparatation for a rework to get rid of the use of 'struct timeval'
and 'struct timespec' in there, this moves all the portions into
kernel/time/timekeeping.c and marks them as 'static'.
The warp_clock() function here is not as closely related as the others,
but I feel it still makes sense to move it here in order to consolidate
all callers of timekeeping_inject_offset().
Signed-off-by: Arnd Bergmann <arnd(a)arndb.de>
---
include/linux/time.h | 26 ----------
kernel/time/ntp.c | 61 ----------------------
kernel/time/ntp_internal.h | 1 -
kernel/time/time.c | 36 +------------
kernel/time/timekeeping.c | 123 ++++++++++++++++++++++++++++++++++++++++++++-
kernel/time/timekeeping.h | 2 +-
6 files changed, 123 insertions(+), 126 deletions(-)
diff --git a/include/linux/time.h b/include/linux/time.h
index 9bc1f945777c..c0fbad08448f 100644
--- a/include/linux/time.h
+++ b/include/linux/time.h
@@ -134,32 +134,6 @@ static inline bool timeval_valid(const struct timeval *tv)
extern struct timespec timespec_trunc(struct timespec t, unsigned gran);
-/*
- * Validates if a timespec/timeval used to inject a time offset is valid.
- * Offsets can be postive or negative. The value of the timeval/timespec
- * is the sum of its fields, but *NOTE*: the field tv_usec/tv_nsec must
- * always be non-negative.
- */
-static inline bool timeval_inject_offset_valid(const struct timeval *tv)
-{
- /* We don't check the tv_sec as it can be positive or negative */
-
- /* Can't have more microseconds then a second */
- if (tv->tv_usec < 0 || tv->tv_usec >= USEC_PER_SEC)
- return false;
- return true;
-}
-
-static inline bool timespec_inject_offset_valid(const struct timespec *ts)
-{
- /* We don't check the tv_sec as it can be positive or negative */
-
- /* Can't have more nanoseconds then a second */
- if (ts->tv_nsec < 0 || ts->tv_nsec >= NSEC_PER_SEC)
- return false;
- return true;
-}
-
/* Some architectures do not supply their own clocksource.
* This is mainly the case in architectures that get their
* inter-tick times by reading the counter on their interval
diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c
index edf19cc53140..a5e702669d84 100644
--- a/kernel/time/ntp.c
+++ b/kernel/time/ntp.c
@@ -653,67 +653,6 @@ static inline void process_adjtimex_modes(struct timex *txc,
}
-
-/**
- * ntp_validate_timex - Ensures the timex is ok for use in do_adjtimex
- */
-int ntp_validate_timex(struct timex *txc)
-{
- if (txc->modes & ADJ_ADJTIME) {
- /* singleshot must not be used with any other mode bits */
- if (!(txc->modes & ADJ_OFFSET_SINGLESHOT))
- return -EINVAL;
- if (!(txc->modes & ADJ_OFFSET_READONLY) &&
- !capable(CAP_SYS_TIME))
- return -EPERM;
- } else {
- /* In order to modify anything, you gotta be super-user! */
- if (txc->modes && !capable(CAP_SYS_TIME))
- return -EPERM;
- /*
- * if the quartz is off by more than 10% then
- * something is VERY wrong!
- */
- if (txc->modes & ADJ_TICK &&
- (txc->tick < 900000/USER_HZ ||
- txc->tick > 1100000/USER_HZ))
- return -EINVAL;
- }
-
- if (txc->modes & ADJ_SETOFFSET) {
- /* In order to inject time, you gotta be super-user! */
- if (!capable(CAP_SYS_TIME))
- return -EPERM;
-
- if (txc->modes & ADJ_NANO) {
- struct timespec ts;
-
- ts.tv_sec = txc->time.tv_sec;
- ts.tv_nsec = txc->time.tv_usec;
- if (!timespec_inject_offset_valid(&ts))
- return -EINVAL;
-
- } else {
- if (!timeval_inject_offset_valid(&txc->time))
- return -EINVAL;
- }
- }
-
- /*
- * Check for potential multiplication overflows that can
- * only happen on 64-bit systems:
- */
- if ((txc->modes & ADJ_FREQUENCY) && (BITS_PER_LONG == 64)) {
- if (LLONG_MIN / PPM_SCALE > txc->freq)
- return -EINVAL;
- if (LLONG_MAX / PPM_SCALE < txc->freq)
- return -EINVAL;
- }
-
- return 0;
-}
-
-
/*
* adjtimex mainly allows reading (and writing, if superuser) of
* kernel time-keeping variables. used by xntpd.
diff --git a/kernel/time/ntp_internal.h b/kernel/time/ntp_internal.h
index d8a7c11fa71a..74b52cd48209 100644
--- a/kernel/time/ntp_internal.h
+++ b/kernel/time/ntp_internal.h
@@ -7,7 +7,6 @@ extern void ntp_clear(void);
extern u64 ntp_tick_length(void);
extern ktime_t ntp_get_next_leap(void);
extern int second_overflow(time64_t secs);
-extern int ntp_validate_timex(struct timex *);
extern int __do_adjtimex(struct timex *, struct timespec64 *, s32 *);
extern void __hardpps(const struct timespec64 *, const struct timespec64 *);
#endif /* _LINUX_NTP_INTERNAL_H */
diff --git a/kernel/time/time.c b/kernel/time/time.c
index 44a8c1402133..04684e294f00 100644
--- a/kernel/time/time.c
+++ b/kernel/time/time.c
@@ -158,40 +158,6 @@ SYSCALL_DEFINE2(gettimeofday, struct timeval __user *, tv,
}
/*
- * Indicates if there is an offset between the system clock and the hardware
- * clock/persistent clock/rtc.
- */
-int persistent_clock_is_local;
-
-/*
- * Adjust the time obtained from the CMOS to be UTC time instead of
- * local time.
- *
- * This is ugly, but preferable to the alternatives. Otherwise we
- * would either need to write a program to do it in /etc/rc (and risk
- * confusion if the program gets run more than once; it would also be
- * hard to make the program warp the clock precisely n hours) or
- * compile in the timezone information into the kernel. Bad, bad....
- *
- * - TYT, 1992-01-01
- *
- * The best thing to do is to keep the CMOS clock in universal time (UTC)
- * as real UNIX machines always do it. This avoids all headaches about
- * daylight saving times and warping kernel clocks.
- */
-static inline void warp_clock(void)
-{
- if (sys_tz.tz_minuteswest != 0) {
- struct timespec adjust;
-
- persistent_clock_is_local = 1;
- adjust.tv_sec = sys_tz.tz_minuteswest * 60;
- adjust.tv_nsec = 0;
- timekeeping_inject_offset(&adjust);
- }
-}
-
-/*
* In case for some reason the CMOS clock has not already been running
* in UTC, but in some local time: The first time we set the timezone,
* we will warp the clock so that it is ticking UTC time instead of
@@ -224,7 +190,7 @@ int do_sys_settimeofday64(const struct timespec64 *tv, const struct timezone *tz
if (firsttime) {
firsttime = 0;
if (!tv)
- warp_clock();
+ timekeeping_warp_clock();
}
}
if (tv)
diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c
index 8af77006e937..679dbfbea419 100644
--- a/kernel/time/timekeeping.c
+++ b/kernel/time/timekeeping.c
@@ -1300,13 +1300,39 @@ int do_settimeofday64(const struct timespec64 *ts)
}
EXPORT_SYMBOL(do_settimeofday64);
+/*
+ * Validates if a timespec/timeval used to inject a time offset is valid.
+ * Offsets can be postive or negative. The value of the timeval/timespec
+ * is the sum of its fields, but *NOTE*: the field tv_usec/tv_nsec must
+ * always be non-negative.
+ */
+static inline bool timeval_inject_offset_valid(const struct timeval *tv)
+{
+ /* We don't check the tv_sec as it can be positive or negative */
+
+ /* Can't have more microseconds then a second */
+ if (tv->tv_usec < 0 || tv->tv_usec >= USEC_PER_SEC)
+ return false;
+ return true;
+}
+
+static inline bool timespec_inject_offset_valid(const struct timespec *ts)
+{
+ /* We don't check the tv_sec as it can be positive or negative */
+
+ /* Can't have more nanoseconds then a second */
+ if (ts->tv_nsec < 0 || ts->tv_nsec >= NSEC_PER_SEC)
+ return false;
+ return true;
+}
+
/**
* timekeeping_inject_offset - Adds or subtracts from the current time.
* @tv: pointer to the timespec variable containing the offset
*
* Adds or subtracts an offset value from the current time.
*/
-int timekeeping_inject_offset(struct timespec *ts)
+static int timekeeping_inject_offset(struct timespec *ts)
{
struct timekeeper *tk = &tk_core.timekeeper;
unsigned long flags;
@@ -1345,7 +1371,40 @@ int timekeeping_inject_offset(struct timespec *ts)
return ret;
}
-EXPORT_SYMBOL(timekeeping_inject_offset);
+
+/*
+ * Indicates if there is an offset between the system clock and the hardware
+ * clock/persistent clock/rtc.
+ */
+int persistent_clock_is_local;
+
+/*
+ * Adjust the time obtained from the CMOS to be UTC time instead of
+ * local time.
+ *
+ * This is ugly, but preferable to the alternatives. Otherwise we
+ * would either need to write a program to do it in /etc/rc (and risk
+ * confusion if the program gets run more than once; it would also be
+ * hard to make the program warp the clock precisely n hours) or
+ * compile in the timezone information into the kernel. Bad, bad....
+ *
+ * - TYT, 1992-01-01
+ *
+ * The best thing to do is to keep the CMOS clock in universal time (UTC)
+ * as real UNIX machines always do it. This avoids all headaches about
+ * daylight saving times and warping kernel clocks.
+ */
+void timekeeping_warp_clock(void)
+{
+ if (sys_tz.tz_minuteswest != 0) {
+ struct timespec adjust;
+
+ persistent_clock_is_local = 1;
+ adjust.tv_sec = sys_tz.tz_minuteswest * 60;
+ adjust.tv_nsec = 0;
+ timekeeping_inject_offset(&adjust);
+ }
+}
/**
* __timekeeping_set_tai_offset - Sets the TAI offset from UTC and monotonic
@@ -2290,6 +2349,66 @@ ktime_t ktime_get_update_offsets_now(unsigned int *cwsseq, ktime_t *offs_real,
}
/**
+ * ntp_validate_timex - Ensures the timex is ok for use in do_adjtimex
+ */
+static int ntp_validate_timex(struct timex *txc)
+{
+ if (txc->modes & ADJ_ADJTIME) {
+ /* singleshot must not be used with any other mode bits */
+ if (!(txc->modes & ADJ_OFFSET_SINGLESHOT))
+ return -EINVAL;
+ if (!(txc->modes & ADJ_OFFSET_READONLY) &&
+ !capable(CAP_SYS_TIME))
+ return -EPERM;
+ } else {
+ /* In order to modify anything, you gotta be super-user! */
+ if (txc->modes && !capable(CAP_SYS_TIME))
+ return -EPERM;
+ /*
+ * if the quartz is off by more than 10% then
+ * something is VERY wrong!
+ */
+ if (txc->modes & ADJ_TICK &&
+ (txc->tick < 900000/USER_HZ ||
+ txc->tick > 1100000/USER_HZ))
+ return -EINVAL;
+ }
+
+ if (txc->modes & ADJ_SETOFFSET) {
+ /* In order to inject time, you gotta be super-user! */
+ if (!capable(CAP_SYS_TIME))
+ return -EPERM;
+
+ if (txc->modes & ADJ_NANO) {
+ struct timespec ts;
+
+ ts.tv_sec = txc->time.tv_sec;
+ ts.tv_nsec = txc->time.tv_usec;
+ if (!timespec_inject_offset_valid(&ts))
+ return -EINVAL;
+
+ } else {
+ if (!timeval_inject_offset_valid(&txc->time))
+ return -EINVAL;
+ }
+ }
+
+ /*
+ * Check for potential multiplication overflows that can
+ * only happen on 64-bit systems:
+ */
+ if ((txc->modes & ADJ_FREQUENCY) && (BITS_PER_LONG == 64)) {
+ if (LLONG_MIN / PPM_SCALE > txc->freq)
+ return -EINVAL;
+ if (LLONG_MAX / PPM_SCALE < txc->freq)
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+
+/**
* do_adjtimex() - Accessor function to NTP __do_adjtimex function
*/
int do_adjtimex(struct timex *txc)
diff --git a/kernel/time/timekeeping.h b/kernel/time/timekeeping.h
index d0914676d4c5..44aec7893cdd 100644
--- a/kernel/time/timekeeping.h
+++ b/kernel/time/timekeeping.h
@@ -10,7 +10,7 @@ extern ktime_t ktime_get_update_offsets_now(unsigned int *cwsseq,
extern int timekeeping_valid_for_hres(void);
extern u64 timekeeping_max_deferment(void);
-extern int timekeeping_inject_offset(struct timespec *ts);
+extern void timekeeping_warp_clock(void);
extern int timekeeping_suspend(void);
extern void timekeeping_resume(void);
--
2.9.0
On 17/05/2022 09:51, Arnaud Panaïotis wrote:
> Hello,
>
> I'm working for a client to generate embedded 32-bits Linux Kernel working after y2038 issue.
>
> I generated a 5.15 Kernel thought Buildroot with Coreutils 9.0, GCC 11.2.0, Binutils 2.37, Glibc 2.34-9 and CFLAGS -D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64 -D_TIME_BITS=64.
>
> I encounter an issue while working with OpenSSH (I initially contacted them before).
To clarify: did you build just openssh with -D_TIME_BITS=64, or did
you build the user space
this way?
> After 2038, /usr/sbin/sshd does not create an error but it child does generate this one:
> daemon() failed: Value too large for defined data type
>
> This happend here in sshd.c:
>
> 2019 /*
> 2020 * If not in debugging mode, not started from inetd and not already
> 2021 * daemonized (eg re-exec via SIGHUP), disconnect from the controlling
> 2022 * terminal, and fork. The original process exits.
> 2023 */
> 2024 already_daemon = daemonized();
> 2025 if (!(debug_flag || inetd_flag || no_daemon_flag || already_daemon)) {
> 2026
> 2027 if (daemon(0, 0) == -1)
> 2028 fatal("daemon() failed: %.200s", strerror(errno));
My guess is that there are parts of glibc that are not fully
y2038-safe at the moment, but
merely provide the interfaces for time64 applications.
In the glibc code, I see
int
daemon (int nochdir, int noclose)
{
...
if ((fd = __open_nocancel(_PATH_DEVNULL, O_RDWR, 0)) != -1
&& (__builtin_expect (__fstat64 (fd, &st), 0)
== 0)) {
...
} else {
__close_nocancel_nostatus (fd);
return -1;
}
return (0);
}
__fstatat64 (int fd, const char *file, struct stat64 *buf, int flags)
{
struct __stat64_t64 st_t64;
return __fstatat64_time64 (fd, file, &st_t64, flags)
?: __cp_stat64_t64_stat64 (&st_t64, buf);
}
If I'm reading this correctly, daemon() internally uses the time32
version of 'stat', which
fails for files with out-of-range timestamps. Are you able to rebuild
the ssh binary
(or your entire distro, if that's easier) against musl-1.2.x instead
of glibc to see if the
same thing happens there?
Arnd
> To reproduce:
>
> # date -s "2040-05-12"
> # hwclock --systohc
> # reboot
> # /usr/sbin/sshd
>
> Note this error occurs only after the reboot, and setting a date before 2038 also require a reboot to remove the error.
>
> strace and gdb trace linked.
>
> Let me know if you need additional information.
Hi,
We are interested in testing your product for an article, video and review in CeroLag.You can contact me WeChat Carl20190526.
We remain pending.
Greetings