fix hangs in localtime for near-overflowing time_t values on 64-bit archs

diff --git a/src/time/localtime_r.c b/src/time/localtime_r.c
index c52678f..1d43d9f 100644 (file)
--- a/src/time/localtime_r.c
+++ b/src/time/localtime_r.c
@@ -4,6 +4,12 @@
 
 struct tm *__localtime_r(const time_t *restrict t, struct tm *restrict tm)
 {
+       /* Reject time_t values whose year would overflow int because
+        * __secs_to_zone cannot safely handle them. */
+       if (*t < INT_MIN * 31622400LL || *t > INT_MAX * 31622400LL) {
+               errno = EOVERFLOW;
+               return 0;
+       }
        __secs_to_zone(*t, 0, &tm->tm_isdst, &tm->__tm_gmtoff, 0, &tm->__tm_zone);
        if (__secs_to_tm((long long)*t - tm->__tm_gmtoff, tm) < 0) {
                errno = EOVERFLOW;