From fa7af8b1bb6dfca7a0c8541683a9bfffbc8dd345 Mon Sep 17 00:00:00 2001 From: Roel Kluin Date: Tue, 31 Mar 2009 15:25:00 -0700 Subject: [PATCH] rtc: test before subtraction on unsigned new_alarm is unsigned so test before the subtraction. [akpm@linux-foundation.org: time-wrapping fix] Signed-off-by: Roel Kluin Cc: David Brownell Cc: Alessandro Zummo Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/rtc/rtc-ds1374.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/rtc/rtc-ds1374.c b/drivers/rtc/rtc-ds1374.c index a5b0fc09f0c6..4d32e328f6cd 100644 --- a/drivers/rtc/rtc-ds1374.c +++ b/drivers/rtc/rtc-ds1374.c @@ -222,16 +222,16 @@ static int ds1374_set_alarm(struct device *dev, struct rtc_wkalrm *alarm) rtc_tm_to_time(&alarm->time, &new_alarm); rtc_tm_to_time(&now, &itime); - new_alarm -= itime; - /* This can happen due to races, in addition to dates that are * truly in the past. To avoid requiring the caller to check for * races, dates in the past are assumed to be in the recent past * (i.e. not something that we'd rather the caller know about via * an error), and the alarm is set to go off as soon as possible. */ - if (new_alarm <= 0) + if (time_before_eq(new_alarm, itime)) new_alarm = 1; + else + new_alarm -= itime; mutex_lock(&ds1374->mutex);