Flush the node when NTA expires

When NTA expires the name's node should be flushed from the view's
cache as it's done when the NTA is manually removed using a rndc
command.

(cherry picked from commit 1899a3318cb944be8fa35d02a35db161c3093375)

diff --git a/lib/dns/nta.c b/lib/dns/nta.c
index 0dc3a65a43e2f4b9bd41077422a7c55e751f0dbc..b3b50b4ac8ab90abb738f7985ef095735cd766bd 100644 (file)
--- a/lib/dns/nta.c
+++ b/lib/dns/nta.c
@@ -375,6 +375,7 @@ delete_expired(void *arg) {
        isc_result_t result;
        dns_qp_t *qp = NULL;
        void *pval = NULL;
+       dns_view_t *view = NULL;
 
        REQUIRE(VALID_NTATABLE(ntatable));
 
@@ -389,6 +390,17 @@ delete_expired(void *arg) {
                isc_log_write(dns_lctx, DNS_LOGCATEGORY_DNSSEC,
                              DNS_LOGMODULE_NTA, ISC_LOG_INFO,
                              "deleting expired NTA at %s", nb);
+
+               /*
+                * Delay the flushing to avoid lock-order-inversion, as
+                * dns_view_flushnode()->dns_adb_flushnames() locks 'adbname',
+                * and it can cause a problem e.g. in dns_ntatable_covered() in
+                * another thread called by the resolver (also involving 'fctx'
+                * lock), or in dns_ntatable_shutdown() (also involving 'view'
+                * lock).
+                */
+               dns_view_weakattach(ntatable->view, &view);
+
                dns_qp_deletename(qp, &nta->name, NULL, NULL);
                dns__nta_shutdown(nta);
                dns__nta_unref(nta);
@@ -396,6 +408,10 @@ delete_expired(void *arg) {
        dns_qp_compact(qp, DNS_QPGC_MAYBE);
        dns_qpmulti_commit(ntatable->table, &qp);
        RWUNLOCK(&ntatable->rwlock, isc_rwlocktype_write);
+       if (view != NULL) {
+               dns_view_flushnode(view, &nta->name, true);
+               dns_view_weakdetach(&view);
+       }
        dns__nta_detach(&nta);
        dns_ntatable_detach(&ntatable);
 }