From 4508b0a1e260b4ebd9f9ae6866d1d7a7c3c6562f Mon Sep 17 00:00:00 2001
From: Mark Andrews <marka@isc.org>
Date: Wed, 18 Jan 2023 15:54:42 +1100
Subject: [PATCH] Add missing node lock when setting node->wild in rbtdb.c

The write node lock needs to be held when setting node->wild in
add_wildcard_magic except when being called from loading_addrdataset
which is used to load the zone without locking during its initial
load.

(cherry picked from commit 81c24b8da270fb06f0d3b9fb5eb92e64d6343ade)
---
 lib/dns/rbtdb.c | 24 ++++++++++++++++--------
 1 file changed, 16 insertions(+), 8 deletions(-)

diff --git a/lib/dns/rbtdb.c b/lib/dns/rbtdb.c
index d1aee54160..bebef1006a 100644
--- a/lib/dns/rbtdb.c
+++ b/lib/dns/rbtdb.c
@@ -2682,7 +2682,7 @@ end:
  * tree_lock(write) must be held.
  */
 static isc_result_t
-add_wildcard_magic(dns_rbtdb_t *rbtdb, const dns_name_t *name) {
+add_wildcard_magic(dns_rbtdb_t *rbtdb, const dns_name_t *name, bool lock) {
 	isc_result_t result;
 	dns_name_t foundname;
 	dns_offsets_t offsets;
@@ -2702,7 +2702,15 @@ add_wildcard_magic(dns_rbtdb_t *rbtdb, const dns_name_t *name) {
 		node->nsec = DNS_RBT_NSEC_NORMAL;
 	}
 	node->find_callback = 1;
+	if (lock) {
+		NODE_LOCK(&rbtdb->node_locks[node->locknum].lock,
+			  isc_rwlocktype_write);
+	}
 	node->wild = 1;
+	if (lock) {
+		NODE_UNLOCK(&rbtdb->node_locks[node->locknum].lock,
+			    isc_rwlocktype_write);
+	}
 	return (ISC_R_SUCCESS);
 }
 
@@ -2710,7 +2718,7 @@ add_wildcard_magic(dns_rbtdb_t *rbtdb, const dns_name_t *name) {
  * tree_lock(write) must be held.
  */
 static isc_result_t
-add_empty_wildcards(dns_rbtdb_t *rbtdb, const dns_name_t *name) {
+add_empty_wildcards(dns_rbtdb_t *rbtdb, const dns_name_t *name, bool lock) {
 	isc_result_t result;
 	dns_name_t foundname;
 	dns_offsets_t offsets;
@@ -2724,7 +2732,7 @@ add_empty_wildcards(dns_rbtdb_t *rbtdb, const dns_name_t *name) {
 		dns_rbtnode_t *node = NULL; /* dummy */
 		dns_name_getlabelsequence(name, n - i, i, &foundname);
 		if (dns_name_iswildcard(&foundname)) {
-			result = add_wildcard_magic(rbtdb, &foundname);
+			result = add_wildcard_magic(rbtdb, &foundname, lock);
 			if (result != ISC_R_SUCCESS) {
 				return (result);
 			}
@@ -2776,11 +2784,11 @@ findnodeintree(dns_rbtdb_t *rbtdb, dns_rbt_t *tree, const dns_name_t *name,
 			dns_rbt_namefromnode(node, &nodename);
 			node->locknum = node->hashval % rbtdb->node_lock_count;
 			if (tree == rbtdb->tree) {
-				add_empty_wildcards(rbtdb, name);
+				add_empty_wildcards(rbtdb, name, true);
 
 				if (dns_name_iswildcard(name)) {
-					result = add_wildcard_magic(rbtdb,
-								    name);
+					result = add_wildcard_magic(rbtdb, name,
+								    true);
 					if (result != ISC_R_SUCCESS) {
 						RWUNLOCK(&rbtdb->tree_lock,
 							 locktype);
@@ -7422,7 +7430,7 @@ loading_addrdataset(void *arg, const dns_name_t *name,
 	if (rdataset->type != dns_rdatatype_nsec3 &&
 	    rdataset->covers != dns_rdatatype_nsec3)
 	{
-		add_empty_wildcards(rbtdb, name);
+		add_empty_wildcards(rbtdb, name, false);
 	}
 
 	if (dns_name_iswildcard(name)) {
@@ -7438,7 +7446,7 @@ loading_addrdataset(void *arg, const dns_name_t *name,
 		if (rdataset->type == dns_rdatatype_nsec3) {
 			return (DNS_R_INVALIDNSEC3);
 		}
-		result = add_wildcard_magic(rbtdb, name);
+		result = add_wildcard_magic(rbtdb, name, false);
 		if (result != ISC_R_SUCCESS) {
 			return (result);
 		}