Since tm->tm_year is the offset relative to 1900, it needs to check for
positive value to avoid overflow in YEARS_REG register.
The system will hang at the following stage on the next boot when overflow
has occurred.
[ 2.221192] systemd[1]: Time has been changed
This patch fixes the above hanging issue by adding bounds checking.
Signed-off-by: Taiyi Wu <taiyity.wu@xxxxxxxx>
Signed-off-by: SZ Lin (林上智) <sz.lin@xxxxxxxx>
---
drivers/rtc/rtc-tps65910.c | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/drivers/rtc/rtc-tps65910.c b/drivers/rtc/rtc-tps65910.c
index d0244d7979fc..6be9f7bb0f1b 100644
--- a/drivers/rtc/rtc-tps65910.c
+++ b/drivers/rtc/rtc-tps65910.c
@@ -105,6 +105,12 @@ static int tps65910_rtc_set_time(struct device *dev, struct rtc_time *tm)
struct tps65910 *tps = dev_get_drvdata(dev->parent);
int ret;
+ if ((tm->tm_year - 100) < 0) {
+ dev_err(dev, "the requested year %d is unsupported\n",
+ 1900 + tm->tm_year);
+ return -EINVAL;
+ }
+
rtc_data[0] = bin2bcd(tm->tm_sec);
rtc_data[1] = bin2bcd(tm->tm_min);
rtc_data[2] = bin2bcd(tm->tm_hour);
--
2.15.1
