From: Colin Vidal <colin@isc.org>
Date: Wed, 17 Dec 2025 14:27:39 +0000 (+0100)
Subject: simplify usage of dns_view_findzonecut()
X-Git-Tag: v9.21.18~34^2
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=e0d7bddc6cdaa42225744c564007bc81e2d1938b;p=thirdparty%2Fbind9.git

simplify usage of dns_view_findzonecut()

As `dns_view_findzonecut()` only returns either ISC_R_SUCCESS or
DNS_R_NXDOMAIN, and since it automatically disassociates the rdatasets
in case of failure, some call sites are simplified.
---

diff --git a/bin/named/server.c b/bin/named/server.c
index 09caf23d554..e381a99851f 100644
--- a/bin/named/server.c
+++ b/bin/named/server.c
@@ -6598,20 +6598,19 @@ tat_send(void *arg) {
 			domain, &nameservers, NULL, NULL, 0, 0, 0, NULL, NULL,
 			NULL, tat->loop, tat_done, tat, NULL, &tat->rdataset,
 			&tat->sigrdataset, &tat->fetch);
+
+		/*
+		 * dns_resolver_createfetch() will create its own copy of
+		 * nameservers.
+		 */
+		dns_rdataset_cleanup(&nameservers);
 	}
 
 	/*
 	 * 'domain' holds the dns_name_t pointer inside a dst_key_t structure.
 	 * dns_resolver_createfetch() creates its own copy of 'domain' if it
 	 * succeeds.  Thus, 'domain' is not freed here.
-	 *
-	 * Even if dns_view_findzonecut() returned something else than
-	 * ISC_R_SUCCESS, it still could have associated 'nameservers'.
-	 * dns_resolver_createfetch() creates its own copy of 'nameservers' if
-	 * it succeeds.  Thus, we need to check whether 'nameservers' is
-	 * associated and release it if it is.
 	 */
-	dns_rdataset_cleanup(&nameservers);
 
 	if (result != ISC_R_SUCCESS) {
 		dns_view_detach(&tat->view);
diff --git a/lib/dns/adb.c b/lib/dns/adb.c
index 0bdf4a9ad96..402c1392f47 100644
--- a/lib/dns/adb.c
+++ b/lib/dns/adb.c
@@ -2738,12 +2738,8 @@ fetch_name(dns_adbname_t *adbname, bool start_at_zone, bool no_validation,
 		DP(ENTER_LEVEL, "fetch_name: starting at zone for name %p",
 		   adbname);
 		name = dns_fixedname_initname(&fixed);
-		result = dns_view_findzonecut(adb->view, adbname->name, name,
-					      NULL, 0, 0, true, false,
-					      &rdataset, NULL);
-		if (result != ISC_R_SUCCESS && result != DNS_R_HINT) {
-			goto cleanup;
-		}
+		CHECK(dns_view_findzonecut(adb->view, adbname->name, name, NULL,
+					   0, 0, true, false, &rdataset, NULL));
 		nameservers = &rdataset;
 		options |= DNS_FETCHOPT_UNSHARED;
 	} else if (adb->view->qminimization) {
diff --git a/lib/dns/include/dns/view.h b/lib/dns/include/dns/view.h
index 1c3bbdb06e3..d65a0d07852 100644
--- a/lib/dns/include/dns/view.h
+++ b/lib/dns/include/dns/view.h
@@ -724,9 +724,9 @@ dns_view_findzonecut(dns_view_t *view, const dns_name_t *name,
  *
  * Returns:
  *
- *\li	#ISC_R_SUCCESS				Success.
- *
- *\li	Many other results are possible.
+ *\li	#ISC_R_SUCCESS  If a delegation is found;
+ *\li   #DNS_R_NXDOMAIN	If no delegation is found; 'rdataset' and 'sigrdataset'
+ *                      are disassociated.
  */
 
 isc_result_t
diff --git a/lib/dns/resolver.c b/lib/dns/resolver.c
index c93f4951cac..53174814219 100644
--- a/lib/dns/resolver.c
+++ b/lib/dns/resolver.c
@@ -4501,22 +4501,8 @@ resume_qmin(void *arg) {
 				      &fctx->nameservers, NULL);
 	FCTXTRACEN("resume_qmin findzonecut", fname, result);
 
-	/*
-	 * DNS_R_NXDOMAIN here means we have not loaded the root zone
-	 * mirror yet - but DNS_R_NXDOMAIN is not a valid return value
-	 * when doing recursion, we need to patch it.
-	 *
-	 * CNAME or DNAME means zone were added with that record
-	 * after the start of a recursion. It means we do not have
-	 * initialized correct hevent->foundname and have to fail.
-	 */
-	if (result == DNS_R_NXDOMAIN || result == DNS_R_CNAME ||
-	    result == DNS_R_DNAME)
-	{
-		result = DNS_R_SERVFAIL;
-	}
-
 	if (result != ISC_R_SUCCESS) {
+		result = DNS_R_SERVFAIL;
 		goto cleanup;
 	}
 	fcount_decr(fctx);