Merge branch '3777-fix-crash-after-failed-ixfr-from-differences' into 'main'

Resolve "crash after failed ixfr-from-differences on a catalog zone"

Closes #3777

See merge request isc-projects/bind9!7431

CHANGES

@@ -1,3 +1,8 @@
+6115.	[bug]		Unregister db update notify callback before detaching
+			from the previous db inside the catz update notify
+			callback. Also, call the db notify callbacks only after
+			zone_postload() returns successfully. [GL #3777]
+
 6114.	[func]		Run the catalog zone update process on the offload
 			threads. [GL #3881]
 

bin/tests/system/catz/clean.sh

@@ -29,6 +29,7 @@ rm -f ns2/catalog-bad*.db
 rm -f ns2/named.conf.tmp
 rm -f ns3/dom2.example.db ns3/dom13.example.db ns3/dom14.example.db ns3/dom17.example.db ns3/dom18.example.db
 rm -f ns4/__catz__*db
+rm -f ns4/catalog-self.example.db
 rm -f ns[123]/catalog[1234].example.db
 rm -f ns[14]/catalog-tls.example.db
 rm -f nsupdate.out.*

bin/tests/system/catz/ns4/catalog.example.db.in

@@ -0,0 +1,14 @@
+; Copyright (C) Internet Systems Consortium, Inc. ("ISC")
+;
+; SPDX-License-Identifier: MPL-2.0
+;
+; This Source Code Form is subject to the terms of the Mozilla Public
+; License, v. 2.0.  If a copy of the MPL was not distributed with this
+; file, you can obtain one at https://mozilla.org/MPL/2.0/.
+;
+; See the COPYRIGHT file distributed with this work for additional
+; information regarding copyright ownership.
+
+@ 3600 SOA . . 1 86400 3600 86400 3600
+@ 3600 IN NS invalid.
+version IN TXT "1"

bin/tests/system/catz/ns4/named.conf.in

@@ -30,11 +30,15 @@ options {
 	notify-delay 0;
 	recursion no;
 	serial-query-rate 100;
+	ixfr-from-differences yes; // GL #3777
 
 	catalog-zones {
 		zone "catalog-tls.example"
 			min-update-interval 1s
 			default-primaries { 10.53.0.1 key tsig_key tls ephemeral; };
+		zone "catalog-self.example"
+			min-update-interval 1s
+			default-primaries { 10.53.0.4; };
 	};
 };
 
@@ -44,6 +48,12 @@ zone "catalog-tls.example" {
 	primaries { 10.53.0.1 key tsig_key tls ephemeral; };
 };
 
+zone "catalog-self.example" {
+	type primary;
+	file "catalog-self.example.db";
+	notify explicit;
+};
+
 key tsig_key. {
 	secret "LSAnCU+Z";
 	algorithm @DEFAULT_HMAC@;

bin/tests/system/catz/setup.sh

@@ -25,5 +25,6 @@ cp -f ns3/catalog.example.db.in ns3/catalog2.example.db
 cp -f ns1/catalog.example.db.in ns1/catalog3.example.db
 cp -f ns1/catalog.example.db.in ns1/catalog4.example.db
 cp -f ns1/catalog.example.db.in ns1/catalog-tls.example.db
+cp -f ns4/catalog.example.db.in ns4/catalog-self.example.db
 
 mkdir -p ns2/zonedir

bin/tests/system/catz/tests.sh

@@ -2605,5 +2605,23 @@ wait_for_soa @10.53.0.4 tls1.example. dig.out.test$n || ret=1
 if [ $ret -ne 0 ]; then echo_i "failed"; fi
 status=$((status+ret))
 
+##########################################################################
+# GL #3777
+nextpart ns4/named.run >/dev/null
+
+n=$((n+1))
+echo_i "Adding domain self.example. to catalog-self zone without updating the serial ($n)"
+ret=0
+echo "self.zones.catalog-self.example. 3600 IN PTR self.example." >> ns4/catalog-self.example.db
+rndccmd 10.53.0.4 reload || ret=1
+
+n=$((n+1))
+echo_i "Issuing another rndc reload command after 1 second ($n)"
+sleep 1
+rndccmd 10.53.0.4 reload || ret=1
+if [ $ret -ne 0 ]; then echo_i "failed"; fi
+status=$((status+ret))
+
+##########################################################################
 echo_i "exit status: $status"
 [ $status -eq 0 ] || exit 1

lib/dns/catz.c

@@ -910,8 +910,10 @@ dns_catz_get_zone(dns_catz_zones_t *catzs, const dns_name_t *name) {
 	REQUIRE(DNS_CATZ_ZONES_VALID(catzs));
 	REQUIRE(ISC_MAGIC_VALID(name, DNS_NAME_MAGIC));
 
+	LOCK(&catzs->lock);
 	result = isc_ht_find(catzs->zones, name->ndata, name->length,
 			     (void **)&found);
+	UNLOCK(&catzs->lock);
 	if (result != ISC_R_SUCCESS) {
 		return (NULL);
 	}
@@ -2104,6 +2106,8 @@ dns_catz_dbupdate_callback(dns_db_t *db, void *fn_arg) {
 		if (catz->dbversion != NULL) {
 			dns_db_closeversion(catz->db, &catz->dbversion, false);
 		}
+		dns_db_updatenotify_unregister(
+			catz->db, dns_catz_dbupdate_callback, catz->catzs);
 		dns_db_detach(&catz->db);
 		/*
 		 * We're not registering db update callback, it will be

lib/dns/zone.c

@@ -17225,13 +17225,6 @@ zone_loaddone(void *arg, isc_result_t result) {
 		dns_zone_catz_disable_db(zone, load->db);
 	}
 
-	tresult = dns_db_endload(load->db, &load->callbacks);
-	if (tresult != ISC_R_SUCCESS &&
-	    (result == ISC_R_SUCCESS || result == DNS_R_SEENINCLUDE))
-	{
-		result = tresult;
-	}
-
 	/*
 	 * Lock hierarchy: zmgr, zone, raw.
 	 */
@@ -17250,9 +17243,13 @@ again:
 			goto again;
 		}
 	}
-	(void)zone_postload(zone, load->db, load->loadtime, result);
+	tresult = zone_postload(zone, load->db, load->loadtime, result);
+	if (tresult != ISC_R_SUCCESS &&
+	    (result == ISC_R_SUCCESS || result == DNS_R_SEENINCLUDE))
+	{
+		result = tresult;
+	}
 	DNS_ZONE_CLRFLAG(zone, DNS_ZONEFLG_LOADING);
-	zone_idetach(&load->callbacks.zone);
 	/*
 	 * Leave the zone frozen if the reload fails.
 	 */
@@ -17269,6 +17266,12 @@ again:
 	}
 	UNLOCK_ZONE(zone);
 
+	(void)dns_db_endload(load->db, &load->callbacks);
+
+	LOCK_ZONE(zone);
+	zone_idetach(&load->callbacks.zone);
+	UNLOCK_ZONE(zone);
+
 	dns_db_detach(&load->db);
 	if (zone->loadctx != NULL) {
 		dns_loadctx_detach(&zone->loadctx);