network-generator: allow empty hostname

Fixes #14319.

(cherry picked from commit 21a925a4ac7955e7d7e6cfd477e96d3a2aaee7db)
(cherry picked from commit efd5b1d443fee81a48939e3f86e7feb338f26211)

1 files changed, 6 insertions, 4 deletions

diff --git a/src/network/generator/network-generator.c b/src/network/generator/network-generator.c
index 0b5af33566..95fcd945c9 100644
--- a/src/network/generator/network-generator.c
+++ b/src/network/generator/network-generator.c
@@ -574,7 +574,7 @@ static int parse_netmask_or_prefixlen(int family, const char **value, unsigned c
 
 static int parse_cmdline_ip_address(Context *context, int family, const char *value) {
         union in_addr_union addr = {}, peer = {}, gateway = {};
-        const char *hostname, *ifname, *dhcp_type, *dns, *p;
+        const char *hostname = NULL, *ifname, *dhcp_type, *dns, *p;
         unsigned char prefixlen;
         int r;
 
@@ -599,9 +599,11 @@ static int parse_cmdline_ip_address(Context *context, int family, const char *va
         if (!p)
                 return -EINVAL;
 
-        hostname = strndupa(value, p - value);
-        if (!hostname_is_valid(hostname, false))
-                return -EINVAL;
+        if (p != value) {
+                hostname = strndupa(value, p - value);
+                if (!hostname_is_valid(hostname, false))
+                        return -EINVAL;
+        }
 
         value = p + 1;