forked from mirrors/linux
074b01a51d
Users may call 'ioctl' and pass a very big value on 'tm->tm_year'. It can be overflowed in 'int' after add 1900. In function 'rtc_month_days' and 'mktime64', also treated it as an 'unsigned' parameter. UBSAN: Undefined behaviour in drivers/rtc/rtc-lib.c:103:59 signed integer overflow: 2147483647 + 1900 cannot be represented in type 'int' UBSAN: Undefined behaviour in drivers/rtc/rtc-lib.c:119:30 signed integer overflow: 2147483647 + 1900 cannot be represented in type 'int' So, covert it to 'unsigned' explicitly. Signed-off-by: ZhangXiaoxu <zhangxiaoxu5@huawei.com> Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
148 lines
3.4 KiB
C
148 lines
3.4 KiB
C
/*
|
|
* rtc and date/time utility functions
|
|
*
|
|
* Copyright (C) 2005-06 Tower Technologies
|
|
* Author: Alessandro Zummo <a.zummo@towertech.it>
|
|
*
|
|
* based on arch/arm/common/rtctime.c and other bits
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License version 2 as
|
|
* published by the Free Software Foundation.
|
|
*/
|
|
|
|
#include <linux/export.h>
|
|
#include <linux/rtc.h>
|
|
|
|
static const unsigned char rtc_days_in_month[] = {
|
|
31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31
|
|
};
|
|
|
|
static const unsigned short rtc_ydays[2][13] = {
|
|
/* Normal years */
|
|
{ 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334, 365 },
|
|
/* Leap years */
|
|
{ 0, 31, 60, 91, 121, 152, 182, 213, 244, 274, 305, 335, 366 }
|
|
};
|
|
|
|
#define LEAPS_THRU_END_OF(y) ((y)/4 - (y)/100 + (y)/400)
|
|
|
|
/*
|
|
* The number of days in the month.
|
|
*/
|
|
int rtc_month_days(unsigned int month, unsigned int year)
|
|
{
|
|
return rtc_days_in_month[month] + (is_leap_year(year) && month == 1);
|
|
}
|
|
EXPORT_SYMBOL(rtc_month_days);
|
|
|
|
/*
|
|
* The number of days since January 1. (0 to 365)
|
|
*/
|
|
int rtc_year_days(unsigned int day, unsigned int month, unsigned int year)
|
|
{
|
|
return rtc_ydays[is_leap_year(year)][month] + day-1;
|
|
}
|
|
EXPORT_SYMBOL(rtc_year_days);
|
|
|
|
|
|
/*
|
|
* rtc_time64_to_tm - Converts time64_t to rtc_time.
|
|
* Convert seconds since 01-01-1970 00:00:00 to Gregorian date.
|
|
*/
|
|
void rtc_time64_to_tm(time64_t time, struct rtc_time *tm)
|
|
{
|
|
unsigned int month, year, secs;
|
|
int days;
|
|
|
|
/* time must be positive */
|
|
days = div_s64_rem(time, 86400, &secs);
|
|
|
|
/* day of the week, 1970-01-01 was a Thursday */
|
|
tm->tm_wday = (days + 4) % 7;
|
|
|
|
year = 1970 + days / 365;
|
|
days -= (year - 1970) * 365
|
|
+ LEAPS_THRU_END_OF(year - 1)
|
|
- LEAPS_THRU_END_OF(1970 - 1);
|
|
while (days < 0) {
|
|
year -= 1;
|
|
days += 365 + is_leap_year(year);
|
|
}
|
|
tm->tm_year = year - 1900;
|
|
tm->tm_yday = days + 1;
|
|
|
|
for (month = 0; month < 11; month++) {
|
|
int newdays;
|
|
|
|
newdays = days - rtc_month_days(month, year);
|
|
if (newdays < 0)
|
|
break;
|
|
days = newdays;
|
|
}
|
|
tm->tm_mon = month;
|
|
tm->tm_mday = days + 1;
|
|
|
|
tm->tm_hour = secs / 3600;
|
|
secs -= tm->tm_hour * 3600;
|
|
tm->tm_min = secs / 60;
|
|
tm->tm_sec = secs - tm->tm_min * 60;
|
|
|
|
tm->tm_isdst = 0;
|
|
}
|
|
EXPORT_SYMBOL(rtc_time64_to_tm);
|
|
|
|
/*
|
|
* Does the rtc_time represent a valid date/time?
|
|
*/
|
|
int rtc_valid_tm(struct rtc_time *tm)
|
|
{
|
|
if (tm->tm_year < 70
|
|
|| ((unsigned)tm->tm_mon) >= 12
|
|
|| tm->tm_mday < 1
|
|
|| tm->tm_mday > rtc_month_days(tm->tm_mon, ((unsigned)tm->tm_year + 1900))
|
|
|| ((unsigned)tm->tm_hour) >= 24
|
|
|| ((unsigned)tm->tm_min) >= 60
|
|
|| ((unsigned)tm->tm_sec) >= 60)
|
|
return -EINVAL;
|
|
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL(rtc_valid_tm);
|
|
|
|
/*
|
|
* rtc_tm_to_time64 - Converts rtc_time to time64_t.
|
|
* Convert Gregorian date to seconds since 01-01-1970 00:00:00.
|
|
*/
|
|
time64_t rtc_tm_to_time64(struct rtc_time *tm)
|
|
{
|
|
return mktime64(((unsigned)tm->tm_year + 1900), tm->tm_mon + 1,
|
|
tm->tm_mday, tm->tm_hour, tm->tm_min, tm->tm_sec);
|
|
}
|
|
EXPORT_SYMBOL(rtc_tm_to_time64);
|
|
|
|
/*
|
|
* Convert rtc_time to ktime
|
|
*/
|
|
ktime_t rtc_tm_to_ktime(struct rtc_time tm)
|
|
{
|
|
return ktime_set(rtc_tm_to_time64(&tm), 0);
|
|
}
|
|
EXPORT_SYMBOL_GPL(rtc_tm_to_ktime);
|
|
|
|
/*
|
|
* Convert ktime to rtc_time
|
|
*/
|
|
struct rtc_time rtc_ktime_to_tm(ktime_t kt)
|
|
{
|
|
struct timespec64 ts;
|
|
struct rtc_time ret;
|
|
|
|
ts = ktime_to_timespec64(kt);
|
|
/* Round up any ns */
|
|
if (ts.tv_nsec)
|
|
ts.tv_sec++;
|
|
rtc_time64_to_tm(ts.tv_sec, &ret);
|
|
return ret;
|
|
}
|
|
EXPORT_SYMBOL_GPL(rtc_ktime_to_tm);
|