resolve: synthesize null address, IPv4 broadcast address, or invalid domain

These are filtered in `dns_scope_good_domain()`, but not synthesized. Fixes #22229.
2022-01-24 06:46:50 +09:00
parent 3b2ac14ac4
commit 46b53e8035
1 changed files with 8 additions and 0 deletions
@@ -397,6 +397,14 @@ int dns_synthesize_answer(
                if (dns_name_is_empty(name)) {
                        /* Do nothing. */

+                } else if (dns_name_endswith(name, "0.in-addr.arpa") > 0 ||
+                           dns_name_equal(name, "255.255.255.255.in-addr.arpa") > 0 ||
+                           dns_name_equal(name, "0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.ip6.arpa") > 0 ||
+                           dns_name_endswith(name, "invalid") > 0) {
+
+                        nxdomain = true;
+                        continue;
+
                } else if (is_localhost(name)) {

                        r = synthesize_localhost_rr(m, key, ifindex, &answer);