From 73442daf2ea85e2a779396b76b1a39b10188ecb5 Mon Sep 17 00:00:00 2001 From: Jan Altenberg Date: Tue, 2 Sep 2008 14:36:05 -0700 Subject: [PATCH] rtc_time_to_tm: fix signed/unsigned arithmetic commit 945185a69daa457c4c5e46e47f4afad7dcea734f ("rtc: rtc_time_to_tm: use unsigned arithmetic") changed the some types in rtc_time_to_tm() to unsigned: void rtc_time_to_tm(unsigned long time, struct rtc_time *tm) { - register int days, month, year; + unsigned int days, month, year; This doesn't work for all cases, because days is checked for < 0 later on: if (days < 0) { year -= 1; days += 365 + LEAP_YEAR(year); } I think the correct fix would be to keep days signed and do an appropriate cast later on. Signed-off-by: Jan Altenberg Cc: Maciej W. Rozycki Cc: Alessandro Zummo Cc: David Brownell Cc: Dmitri Vorobiev Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/rtc/rtc-lib.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/rtc/rtc-lib.c b/drivers/rtc/rtc-lib.c index 9f996ec881c..dd70bf73ce9 100644 --- a/drivers/rtc/rtc-lib.c +++ b/drivers/rtc/rtc-lib.c @@ -51,10 +51,11 @@ EXPORT_SYMBOL(rtc_year_days); */ void rtc_time_to_tm(unsigned long time, struct rtc_time *tm) { - unsigned int days, month, year; + unsigned int month, year; + int days; days = time / 86400; - time -= days * 86400; + time -= (unsigned int) days * 86400; /* day of the week, 1970-01-01 was a Thursday */ tm->tm_wday = (days + 4) % 7; -- 2.41.1