[rtc-linux] [PATCH v2] drivers/rtc/rtc-m41t80.c: avoid out of range year values
From: Stefan Christ <hidden>
Date: 2016-03-15 13:22:27
Subsystem:
real time clock (rtc) subsystem, the rest · Maintainers:
Alexandre Belloni, Linus Torvalds
Avoid saving an out of range year value to the RTC. Reading that value
from the RTC again returns a totally wrong time value. For Example
$ timedatectl set-ntp no
$ timedatectl set-time "1990-01-01 12:12:00"
# Reboot
rtc-m41t80 0-0068: setting system clock to 2090-01-01 12:12:35 UTC (3786955955)
Signed-off-by: Stefan Christ <redacted>
---
v2: fix checkpatch warning in if
v2: align arguments in dev_err call
---
drivers/rtc/rtc-m41t80.c | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/drivers/rtc/rtc-m41t80.c b/drivers/rtc/rtc-m41t80.c
index a82937e..d107a8e 100644
--- a/drivers/rtc/rtc-m41t80.c
+++ b/drivers/rtc/rtc-m41t80.c@@ -176,7 +176,13 @@ static int m41t80_set_datetime(struct i2c_client *client, struct rtc_time *tm) bin2bcd(tm->tm_mday) | (buf[M41T80_REG_DAY] & ~0x3f); buf[M41T80_REG_MON] = bin2bcd(tm->tm_mon + 1) | (buf[M41T80_REG_MON] & ~0x1f); + /* assume 20YY not 19YY */ + if (tm->tm_year < 100 || tm->tm_year > 199) { + dev_err(&client->dev, "Year must be between 2000 and 2099. It's %d.\n", + tm->tm_year + 1900); + return -EINVAL; + } buf[M41T80_REG_YEAR] = bin2bcd(tm->tm_year % 100); if (i2c_transfer(client->adapter, msgs, 1) != 1) {
--
1.9.1
--
--
You received this message because you are subscribed to "rtc-linux".
Membership options at http://groups.google.com/group/rtc-linux .
Please read http://groups.google.com/group/rtc-linux/web/checklist
before submitting a driver.
---
You received this message because you are subscribed to the Google Groups "rtc-linux" group.
To unsubscribe from this group and stop receiving emails from it, send an email to rtc-linux+unsubscribe@googlegroups.com.
For more options, visit https://groups.google.com/d/optout.