diff options
| author | ZhangXiaoxu <zhangxiaoxu5@huawei.com> | 2018-12-20 17:36:56 +0800 |
|---|---|---|
| committer | Alexandre Belloni <alexandre.belloni@bootlin.com> | 2019-01-10 22:02:44 +0100 |
| commit | 074b01a51d058f4216b7ce541e96b778aa6af60d (patch) | |
| tree | f28558c2770740be30cdc607b1b5ca21a021c2e9 /drivers/rtc/lib.c | |
| parent | 7c617e0c5f37d2f681b3a568c3642115a32b7427 (diff) | |
| download | linux-074b01a51d058f4216b7ce541e96b778aa6af60d.tar.bz2 | |
rtc: Fix UBSAN overflow warning
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>
Diffstat (limited to 'drivers/rtc/lib.c')
| -rw-r--r-- | drivers/rtc/lib.c | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/drivers/rtc/lib.c b/drivers/rtc/lib.c index ef160da84220..9714cb3d1e29 100644 --- a/drivers/rtc/lib.c +++ b/drivers/rtc/lib.c @@ -100,7 +100,7 @@ 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, tm->tm_year + 1900) + || 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) @@ -116,8 +116,8 @@ EXPORT_SYMBOL(rtc_valid_tm); */ time64_t rtc_tm_to_time64(struct rtc_time *tm) { - return mktime64(tm->tm_year + 1900, tm->tm_mon + 1, tm->tm_mday, - tm->tm_hour, tm->tm_min, tm->tm_sec); + 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); |