Do not return any error for empty name. Just returns empty answer.
Before:
---
$ dig .
; <<>> DiG 9.16.24-RH <<>> .
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: SERVFAIL, id: 13617
;; flags: qr aa rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 0, ADDITIONAL: 1
;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 65494
;; QUESTION SECTION:
;. IN A
;; Query time: 0 msec
;; SERVER: 127.0.0.53#53(127.0.0.53)
;; WHEN: Mon Jan 24 05:49:30 JST 2022
;; MSG SIZE rcvd: 28
---
After:
---
$ dig .
; <<>> DiG 9.16.24-RH <<>> .
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 7957
;; flags: qr aa rd ra ad; QUERY: 1, ANSWER: 0, AUTHORITY: 0, ADDITIONAL: 1
;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 65494
;; QUESTION SECTION:
;. IN A
;; Query time: 1 msec
;; SERVER: 127.0.0.53#53(127.0.0.53)
;; WHEN: Mon Jan 24 06:05:02 JST 2022
;; MSG SIZE rcvd: 28
---
Replaces #22197.
Fixes RHBZ#
2039854 (https://bugzilla.redhat.com/show_bug.cgi?id=
2039854).
if ((SD_RESOLVED_FLAGS_MAKE(s->protocol, s->family, false, false) & flags) == 0)
return DNS_SCOPE_NO;
+ /* Never resolve empty name. */
+ if (dns_name_is_empty(domain))
+ return DNS_SCOPE_NO;
+
/* Never resolve any loopback hostname or IP address via DNS, LLMNR or mDNS. Instead, always rely on
* synthesized RRs for these. */
if (is_localhost(domain) ||
name = dns_resource_key_name(key);
- if (is_localhost(name)) {
+ if (dns_name_is_empty(name)) {
+ /* Do nothing. */
+
+ } else if (is_localhost(name)) {
r = synthesize_localhost_rr(m, key, ifindex, &answer);
if (r < 0)