diff --git a/client/util_posix.c b/client/util_posix.c
index 7704e9d4b..a45dc48e9 100644
--- a/client/util_posix.c
+++ b/client/util_posix.c
@@ -130,7 +130,7 @@ uint64_t msclock(void) {
 #else
 	struct timespec t;
 	clock_gettime(CLOCK_MONOTONIC, &t);
-	return (t.tv_sec * 1000 + t.tv_nsec / 1000000);
+	return ( 1000 * (uint64_t)t.tv_sec + t.tv_nsec / 1000000);
 #endif
 }