lib/timeutils.c:strxxx_iso: test conversion errors

Test for libc time conversion errors in ISO time format functions.

hwclock --utc --noadjfile --predict --date '67768034678846520 seconds'
Segmentation fault

Patched:
hwclock --utc --noadjfile --predict --date '67768034678846520 seconds'
hwclock: time 67768036191695381 is out of range.

Comparable to date(1):
date --date '67768034678846520 seconds'
date: time 67768036191695384 is out of range

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

diff --git a/lib/timeutils.c b/lib/timeutils.c
index 994073700e658ae1b0784d4b8bcf1d84fc80f0c8..dd763ecc38d562a013a504fb0c28f3b6be1bc88d 100644 (file)
--- a/lib/timeutils.c
+++ b/lib/timeutils.c
@@ -460,12 +460,18 @@ static int format_iso_time(struct tm *tm, suseconds_t usec, int flags, char *buf
 int strtimeval_iso(struct timeval *tv, int flags, char *buf, size_t bufsz)
 {
        struct tm tm;
+       struct tm *rc;
 
        if (flags & ISO_GMTIME)
-               gmtime_r(&tv->tv_sec, &tm);
+               rc = gmtime_r(&tv->tv_sec, &tm);
        else
-               localtime_r(&tv->tv_sec, &tm);
-       return format_iso_time(&tm, tv->tv_usec, flags, buf, bufsz);
+               rc = localtime_r(&tv->tv_sec, &tm);
+
+       if (rc)
+               return format_iso_time(&tm, tv->tv_usec, flags, buf, bufsz);
+
+       warnx(_("time %ld is out of range."), tv->tv_sec);
+       return -1;
 }
 
 /* struct tm to ISO 8601 */
@@ -478,12 +484,18 @@ int strtm_iso(struct tm *tm, int flags, char *buf, size_t bufsz)
 int strtime_iso(const time_t *t, int flags, char *buf, size_t bufsz)
 {
        struct tm tm;
+       struct tm *rc;
 
        if (flags & ISO_GMTIME)
-               gmtime_r(t, &tm);
+               rc = gmtime_r(t, &tm);
        else
-               localtime_r(t, &tm);
-       return format_iso_time(&tm, 0, flags, buf, bufsz);
+               rc = localtime_r(t, &tm);
+
+       if (rc)
+               return format_iso_time(&tm, 0, flags, buf, bufsz);
+
+       warnx(_("time %ld is out of range."), (long)t);
+       return -1;
 }
 
 /* relative time functions */