From: J William Piggott <elseifthen@gmx.com>
Date: Sat, 9 Dec 2017 19:01:33 +0000 (-0500)
Subject: lib/timeutils.c: bug fix Segmentation fault
X-Git-Tag: v2.32-rc1~138
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=97772cc329bfa555b38416dc4dcacd4d318560c3;p=thirdparty%2Futil-linux.git

lib/timeutils.c: bug fix Segmentation fault

Use reentrant time functions to avoid sending a NULL pointer to
format_iso_time() (and to be reentrant ;). Followup commits test for
errors and tm_year wrapping (illustrated below).

hwclock --utc --noadjfile --predict --date '67768034678849400 seconds'
Segmentation fault

Patched
hwclock --utc --noadjfile --predict --date '67768034678849400 seconds'
-2147481748-01-00 00:10:46.000000-05:00

Signed-off-by: J William Piggott <elseifthen@gmx.com>
---

diff --git a/lib/timeutils.c b/lib/timeutils.c
index fdaa2d4a95..994073700e 100644
--- a/lib/timeutils.c
+++ b/lib/timeutils.c
@@ -462,9 +462,9 @@ int strtimeval_iso(struct timeval *tv, int flags, char *buf, size_t bufsz)
 	struct tm tm;
 
 	if (flags & ISO_GMTIME)
-		tm = *gmtime(&tv->tv_sec);
+		gmtime_r(&tv->tv_sec, &tm);
 	else
-		tm = *localtime(&tv->tv_sec);
+		localtime_r(&tv->tv_sec, &tm);
 	return format_iso_time(&tm, tv->tv_usec, flags, buf, bufsz);
 }
 
@@ -480,9 +480,9 @@ int strtime_iso(const time_t *t, int flags, char *buf, size_t bufsz)
 	struct tm tm;
 
 	if (flags & ISO_GMTIME)
-		tm = *gmtime(t);
+		gmtime_r(t, &tm);
 	else
-		tm = *localtime(t);
+		localtime_r(t, &tm);
 	return format_iso_time(&tm, 0, flags, buf, bufsz);
 }