Fix detection whether node is active in find_wildcard()

The current code would fail during the write transaction.  The first
header would not match the search->serial and the node might be
incorrectly detected as inactive.

diff --git a/lib/dns/qpzone.c b/lib/dns/qpzone.c
index bbaa16b6875729d6898a69928eaf0f09a322cfc5..5f5de351b2e6112a30f765caad159b921cbf023f 100644 (file)
--- a/lib/dns/qpzone.c
+++ b/lib/dns/qpzone.c
@@ -2769,10 +2769,19 @@ wildcard_blocked(qpz_search_t *search, const dns_name_t *qname,
        return false;
 }
 
+static bool
+node_active(qpz_search_t *search, qpznode_t *node) {
+       DNS_SLABTOP_FOREACH(top, node->data) {
+               if (first_existing_header(top, search->serial) != NULL) {
+                       return true;
+               }
+       }
+       return false;
+}
+
 static isc_result_t
 find_wildcard(qpz_search_t *search, qpznode_t **nodep, const dns_name_t *qname,
              dns_namespace_t nspace) {
-       dns_slabheader_t *found = NULL;
        isc_result_t result = ISC_R_NOTFOUND;
 
        /*
@@ -2800,17 +2809,7 @@ find_wildcard(qpz_search_t *search, qpznode_t **nodep, const dns_name_t *qname,
                 * may not need the information, because it simplifies the
                 * locking and code flow.
                 */
-               DNS_SLABTOP_FOREACH(top, node->data) {
-                       dns_slabheader_t *header = top->header;
-                       if (header->serial <= search->serial &&
-                           !IGNORE(header) && EXISTS(header))
-                       {
-                               found = header;
-                               break;
-                       }
-               }
-
-               active = (found != NULL);
+               active = node_active(search, node);
                wild = node->wild;
                NODE_UNLOCK(nlock, &nlocktype);
 
@@ -2819,6 +2818,7 @@ find_wildcard(qpz_search_t *search, qpznode_t **nodep, const dns_name_t *qname,
                        dns_fixedname_t fwname;
                        dns_name_t *wname = dns_fixedname_initname(&fwname);
                        dns_qpiter_t wit;
+                       bool wactive;
 
                        /*
                         * Construct the wildcard name for this level.
@@ -2840,18 +2840,9 @@ find_wildcard(qpz_search_t *search, qpznode_t **nodep, const dns_name_t *qname,
                                 */
                                nlock = qpzone_get_lock(wnode);
                                NODE_RDLOCK(nlock, &nlocktype);
-                               DNS_SLABTOP_FOREACH(top, wnode->data) {
-                                       dns_slabheader_t *header = top->header;
-                                       if (header->serial <= search->serial &&
-                                           !IGNORE(header) && EXISTS(header))
-                                       {
-                                               found = header;
-                                               break;
-                                       }
-                               }
+                               wactive = node_active(search, wnode);
                                NODE_UNLOCK(nlock, &nlocktype);
-                               if (found != NULL ||
-                                   activeempty(search, &wit, wname))
+                               if (wactive || activeempty(search, &wit, wname))
                                {
                                        if (wildcard_blocked(search, qname,
                                                             wname))