From e9054375028335ef1e2946b80d9765f8e69cbb9c Mon Sep 17 00:00:00 2001
From: Yu Watanabe <watanabe.yu+github@gmail.com>
Date: Wed, 14 Dec 2022 13:40:42 +0900
Subject: [PATCH] sd-id128: also refuse an empty invocation ID

(cherry picked from commit 75fa1f25c08a4b5dc2180893718473be9e4f6bab)

Related: RHEL-27512
---
 man/sd_id128_get_machine.xml       | 3 ++-
 src/libsystemd/sd-id128/sd-id128.c | 3 +++
 2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/man/sd_id128_get_machine.xml b/man/sd_id128_get_machine.xml
index 4f6926fd7d..075caffb2b 100644
--- a/man/sd_id128_get_machine.xml
+++ b/man/sd_id128_get_machine.xml
@@ -139,7 +139,8 @@
 
           <listitem><para>Returned by <function>sd_id128_get_machine()</function> and
           <function>sd_id128_get_machine_app_specific()</function> when <filename>/etc/machine-id</filename>
-          is empty or all zeros.</para></listitem>
+          is empty or all zeros. Also returned by <function>sd_id128_get_invocation()</function> when the
+          invocation ID is all zeros.</para></listitem>
         </varlistentry>
 
         <varlistentry>
diff --git a/src/libsystemd/sd-id128/sd-id128.c b/src/libsystemd/sd-id128/sd-id128.c
index dee0df2396..ec53617fce 100644
--- a/src/libsystemd/sd-id128/sd-id128.c
+++ b/src/libsystemd/sd-id128/sd-id128.c
@@ -285,6 +285,9 @@ _public_ int sd_id128_get_invocation(sd_id128_t *ret) {
                         r = get_invocation_from_keyring(&saved_invocation_id);
                 if (r < 0)
                         return r;
+
+                if (sd_id128_is_null(saved_invocation_id))
+                        return -ENOMEDIUM;
         }
 
         if (ret)