From: George Anzinger <george@mvista.com>
Date: Mon, 14 Nov 2005 00:07:44 +0000 (-0800)
Subject: [PATCH] timespec: normalize off by one errors
X-Git-Tag: v2.6.15-rc2~144
X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=3f39894d1b5c253b10fcb8fbbbcf65a330f6cdc7;p=linux-2.6

[PATCH] timespec: normalize off by one errors

It would appear that the timespec normalize code has an off by one error.
Found in three places.  Thanks to Ben for spotting.

Signed-off-by: George Anzinger<george@mvista.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
---

diff --git a/include/linux/time.h b/include/linux/time.h
index 8e83f4e778..bfbe92d076 100644
--- a/include/linux/time.h
+++ b/include/linux/time.h
@@ -101,7 +101,7 @@ extern struct timespec timespec_trunc(struct timespec t, unsigned gran);
 static inline void
 set_normalized_timespec (struct timespec *ts, time_t sec, long nsec)
 {
-	while (nsec > NSEC_PER_SEC) {
+	while (nsec >= NSEC_PER_SEC) {
 		nsec -= NSEC_PER_SEC;
 		++sec;
 	}
diff --git a/kernel/posix-timers.c b/kernel/posix-timers.c
index ea55c7a1cd..5870efb3e2 100644
--- a/kernel/posix-timers.c
+++ b/kernel/posix-timers.c
@@ -270,7 +270,7 @@ static void tstojiffie(struct timespec *tp, int res, u64 *jiff)
 	long sec = tp->tv_sec;
 	long nsec = tp->tv_nsec + res - 1;
 
-	if (nsec > NSEC_PER_SEC) {
+	if (nsec >= NSEC_PER_SEC) {
 		sec++;
 		nsec -= NSEC_PER_SEC;
 	}
@@ -1209,13 +1209,9 @@ static int do_posix_clock_monotonic_get(clockid_t clock, struct timespec *tp)
 
 	do_posix_clock_monotonic_gettime_parts(tp, &wall_to_mono);
 
-	tp->tv_sec += wall_to_mono.tv_sec;
-	tp->tv_nsec += wall_to_mono.tv_nsec;
+	set_normalized_timespec(tp, tp->tv_sec + wall_to_mono.tv_sec,
+				tp->tv_nsec + wall_to_mono.tv_nsec);
 
-	if ((tp->tv_nsec - NSEC_PER_SEC) > 0) {
-		tp->tv_nsec -= NSEC_PER_SEC;
-		tp->tv_sec++;
-	}
 	return 0;
 }