From: Nick Rosbrook <enr0n@ubuntu.com>
Date: Thu, 18 Sep 2025 13:16:02 +0000 (-0400)
Subject: basic: validate timezones in get_timezones()
X-Git-Tag: v259-rc1~513
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=9fe168a92c87d9b2def3a18d54b0b62c04c4aee0;p=thirdparty%2Fsystemd.git

basic: validate timezones in get_timezones()

Depending on the packaging of tzdata, /usr/share/zoneinfo/tzdata.zi may
reference zones or links that are not actually present on the system.
E.g. on Debian and Ubuntu, there is a tzdata-legacy package that
contains "legacy" zones and links, but they are still referenced in
/usr/share/zoneinfo/tzdata.zi shipped by the main tzdata package.

Right now, get_timezoes() does not validate timezones when building the
list, which makes the following possible:

 $ timedatectl list-timezones | grep "US/Alaska"
 US/Alaska

 $ timedatectl set-timezone US/Alaska
 Failed to set time zone: Invalid or not installed time zone 'US/Alaska'

which feels buggy. Hence, simply validate timezones in get_timezones()
to avoid listing timezones that are not installed.
---

diff --git a/src/basic/time-util.c b/src/basic/time-util.c
index 55931a25461..43ef5e42700 100644
--- a/src/basic/time-util.c
+++ b/src/basic/time-util.c
@@ -1435,6 +1435,10 @@ static int get_timezones_from_zone1970_tab(char ***ret) {
                 if (*cc == '#')
                         continue;
 
+                if (!timezone_is_valid(tz, LOG_DEBUG))
+                        /* Don't list unusable timezones. */
+                        continue;
+
                 r = strv_extend(&zones, tz);
                 if (r < 0)
                         return r;
@@ -1487,6 +1491,10 @@ static int get_timezones_from_tzdata_zi(char ***ret) {
                         /* Not a line we care about. */
                         continue;
 
+                if (!timezone_is_valid(tz, LOG_DEBUG))
+                        /* Don't list unusable timezones. */
+                        continue;
+
                 r = strv_extend(&zones, tz);
                 if (r < 0)
                         return r;