The kernel uses 32-bit signed value(time_t) for seconds since
1970-01-01:00:00:00, so it
will overflow at 2038-01-19 03:14:08 on 32-bit systems. We call this "2038
safety" issue.
As part of addressing 2038 safety for in-kernel uses, convert do_settimeofday()
to use the timespec64 structure, and modify all users of do_settimeofday() to
provide timespec64 structures (via timespec_to_timespec64() as needed).
Signed-off-by: pang.xunlei <pang.xun...@linaro.org>
---
arch/x86/xen/time.c | 10 ++++++++--
drivers/hv/hv_util.c | 4 ++--
drivers/rtc/hctosys.c | 4 +---
drivers/staging/android/alarm-dev.c | 8 +++++---
include/linux/timekeeping.h | 2 +-
kernel/compat.c | 4 +++-
kernel/time/time.c | 13 ++++++++++---
kernel/time/timekeeping.c | 15 +++++++--------
8 files changed, 37 insertions(+), 23 deletions(-)
diff --git a/arch/x86/xen/time.c b/arch/x86/xen/time.c
index a1d430b..cf1b591 100644
--- a/arch/x86/xen/time.c
+++ b/arch/x86/xen/time.c
@@ -486,6 +486,7 @@ static void __init xen_time_init(void)
{
int cpu = smp_processor_id();
struct timespec tp;
+ struct timespec64 tp64;
clocksource_register_hz(&xen_clocksource, NSEC_PER_SEC);
@@ -496,9 +497,14 @@ static void __init xen_time_init(void)
xen_clockevent = &xen_vcpuop_clockevent;
}
- /* Set initial system time with full resolution */
+ /*
+ * Set initial system time with full resolution.
+ * TODO: [2038 safety] xen_read_wallclock() should be changed to use
+ * timespec64 for 2038 safety as soon as possible.
+ */
xen_read_wallclock(&tp);
- do_settimeofday(&tp);
+ tp64 = timespec_to_timespec64(tp);
+ do_settimeofday(&tp64);
setup_force_cpu_cap(X86_FEATURE_TSC);
diff --git a/drivers/hv/hv_util.c b/drivers/hv/hv_util.c
index 3b9c9ef..73b0962 100644
--- a/drivers/hv/hv_util.c
+++ b/drivers/hv/hv_util.c
@@ -166,10 +166,10 @@ static void shutdown_onchannelcallback(void *context)
static inline void do_adj_guesttime(u64 hosttime)
{
s64 host_tns;
- struct timespec host_ts;
+ struct timespec64 host_ts;
host_tns = (hosttime - WLTIMEDELTA) * 100;
- host_ts = ns_to_timespec(host_tns);
+ host_ts = ns_to_timespec64(host_tns);
do_settimeofday(&host_ts);
}
diff --git a/drivers/rtc/hctosys.c b/drivers/rtc/hctosys.c
index c80723f..db71f47 100644
--- a/drivers/rtc/hctosys.c
+++ b/drivers/rtc/hctosys.c
@@ -29,7 +29,6 @@ static int __init rtc_hctosys(void)
struct timespec64 tv = {
.tv_nsec = NSEC_PER_SEC >> 1,
};
- struct timespec ts32;
struct rtc_device *rtc = rtc_class_open(CONFIG_RTC_HCTOSYS_DEVICE);
if (rtc == NULL) {
@@ -55,8 +54,7 @@ static int __init rtc_hctosys(void)
rtc_tm_to_time(&tm, &tv.tv_sec);
- ts32 = timespec64_to_timespec(tv);
- err = do_settimeofday(&ts32);
+ err = do_settimeofday(&tv);
dev_info(rtc->dev.parent,
"setting system clock to "
diff --git a/drivers/staging/android/alarm-dev.c
b/drivers/staging/android/alarm-dev.c
index e2729c8..0385a38 100644
--- a/drivers/staging/android/alarm-dev.c
+++ b/drivers/staging/android/alarm-dev.c
@@ -154,7 +154,6 @@ static int alarm_wait(void)
static int alarm_set_rtc(struct timespec64 *ts)
{
- struct timespec ts32;
struct rtc_time new_rtc_tm;
struct rtc_device *rtc_dev;
unsigned long flags;
@@ -162,8 +161,7 @@ static int alarm_set_rtc(struct timespec64 *ts)
rtc_time_to_tm(ts->tv_sec, &new_rtc_tm);
rtc_dev = alarmtimer_get_rtcdev();
- ts32 = timespec64_to_timespec(*ts);
- rv = do_settimeofday(&ts32);
+ rv = do_settimeofday(ts);
if (rv < 0)
return rv;
if (rtc_dev)
@@ -200,6 +198,10 @@ static int alarm_get_time(enum android_alarm_type
alarm_type,
return rv;
}
+/*
+ * TODO: [2038 safety] alarm_do_ioctl() should be fixed to use timespec64,
+ * once timespec64 is promoted to userspace.
+ */
static long alarm_do_ioctl(struct file *file, unsigned int cmd,
struct timespec *ts)
{
diff --git a/include/linux/timekeeping.h b/include/linux/timekeeping.h
index 64c9c77..6cb9a77 100644
--- a/include/linux/timekeeping.h
+++ b/include/linux/timekeeping.h
@@ -10,7 +10,7 @@ extern int timekeeping_suspended;
* Get and set timeofday
*/
extern void do_gettimeofday(struct timeval *tv);
-extern int do_settimeofday(const struct timespec *tv);
+extern int do_settimeofday(const struct timespec64 *ts);
extern int do_sys_settimeofday(const struct timespec *tv,
const struct timezone *tz);
diff --git a/kernel/compat.c b/kernel/compat.c
index ebb3c36..4362578 100644
--- a/kernel/compat.c
+++ b/kernel/compat.c
@@ -1047,6 +1047,7 @@ COMPAT_SYSCALL_DEFINE1(time, compat_time_t __user *, tloc)
COMPAT_SYSCALL_DEFINE1(stime, compat_time_t __user *, tptr)
{
struct timespec tv;
+ struct timespec64 tv64;
int err;
if (get_user(tv.tv_sec, tptr))
@@ -1058,7 +1059,8 @@ COMPAT_SYSCALL_DEFINE1(stime, compat_time_t __user *,
tptr)
if (err)
return err;
- do_settimeofday(&tv);
+ tv64 = timespec_to_timespec64(tv);
+ do_settimeofday(&tv64);
return 0;
}
diff --git a/kernel/time/time.c b/kernel/time/time.c
index f9521fa..d85fda9 100644
--- a/kernel/time/time.c
+++ b/kernel/time/time.c
@@ -82,6 +82,7 @@ SYSCALL_DEFINE1(time, time_t __user *, tloc)
SYSCALL_DEFINE1(stime, time_t __user *, tptr)
{
struct timespec tv;
+ struct timespec64 tv64;
int err;
if (get_user(tv.tv_sec, tptr))
@@ -93,7 +94,8 @@ SYSCALL_DEFINE1(stime, time_t __user *, tptr)
if (err)
return err;
- do_settimeofday(&tv);
+ tv64 = timespec_to_timespec64(tv);
+ do_settimeofday(&tv64);
return 0;
}
@@ -162,6 +164,7 @@ static inline void warp_clock(void)
int do_sys_settimeofday(const struct timespec *tv, const struct timezone *tz)
{
+ struct timespec64 tv64;
static int firsttime = 1;
int error = 0;
@@ -181,8 +184,12 @@ int do_sys_settimeofday(const struct timespec *tv, const
struct timezone *tz)
warp_clock();
}
}
- if (tv)
- return do_settimeofday(tv);
+
+ if (tv) {
+ tv64 = timespec_to_timespec64(*tv);
+ return do_settimeofday(&tv64);
+ }
+
return 0;
}
diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c
index b58e7cf..fd03819 100644
--- a/kernel/time/timekeeping.c
+++ b/kernel/time/timekeeping.c
@@ -704,17 +704,17 @@ EXPORT_SYMBOL(do_gettimeofday);
/**
* do_settimeofday - Sets the time of day
- * @tv: pointer to the timespec variable containing the new time
+ * @ts: pointer to the timespec64 variable containing the new
time
*
* Sets the time of day to the new time and update NTP and notify hrtimers
*/
-int do_settimeofday(const struct timespec *tv)
+int do_settimeofday(const struct timespec64 *ts)
{
struct timekeeper *tk = &tk_core.timekeeper;
- struct timespec64 ts_delta, xt, tmp;
+ struct timespec64 ts_delta, xt;
unsigned long flags;
- if (!timespec_valid_strict(tv))
+ if (!timespec64_valid_strict(ts))
return -EINVAL;
raw_spin_lock_irqsave(&timekeeper_lock, flags);
@@ -723,13 +723,12 @@ int do_settimeofday(const struct timespec *tv)
timekeeping_forward_now(tk);
xt = tk_xtime(tk);
- ts_delta.tv_sec = tv->tv_sec - xt.tv_sec;
- ts_delta.tv_nsec = tv->tv_nsec - xt.tv_nsec;
+ ts_delta.tv_sec = ts->tv_sec - xt.tv_sec;
+ ts_delta.tv_nsec = ts->tv_nsec - xt.tv_nsec;
tk_set_wall_to_mono(tk, timespec64_sub(tk->wall_to_monotonic,
ts_delta));
- tmp = timespec_to_timespec64(*tv);
- tk_set_xtime(tk, &tmp);
+ tk_set_xtime(tk, ts);
timekeeping_update(tk, TK_CLEAR_NTP | TK_MIRROR | TK_CLOCK_WAS_SET);
--
1.7.9.5
--
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