Enable lame response detection even with disabled lame cache

Previously, when lame cache would be disabled by setting lame-ttl to 0,
it would also disable lame answer detection.  In this commit, we enable
the lame response detection even when the lame cache is disabled.  This
enables stopping answer processing early rather than going through the
whole answer processing flow.

diff --git a/lib/dns/resolver.c b/lib/dns/resolver.c
index eb752e224b654a3d6a396a29d3db43d6203ddf68..edbe344146eaa3dcfa8a41582ab06af4b5c86eaa 100644 (file)
--- a/lib/dns/resolver.c
+++ b/lib/dns/resolver.c
@@ -9655,25 +9655,26 @@ rctx_badserver(respctx_t *rctx, isc_result_t result) {
  */
 static isc_result_t
 rctx_lameserver(respctx_t *rctx) {
-       isc_result_t result;
+       isc_result_t result = ISC_R_SUCCESS;
        fetchctx_t *fctx = rctx->fctx;
        resquery_t *query = rctx->query;
 
-       if (fctx->res->lame_ttl == 0 || ISFORWARDER(query->addrinfo) ||
-           !is_lame(fctx, query->rmessage))
-       {
+       if (ISFORWARDER(query->addrinfo) || !is_lame(fctx, query->rmessage)) {
                return (ISC_R_SUCCESS);
        }
 
        inc_stats(fctx->res, dns_resstatscounter_lame);
        log_lame(fctx, query->addrinfo);
-       result = dns_adb_marklame(fctx->adb, query->addrinfo, fctx->name,
-                                 fctx->type, rctx->now + fctx->res->lame_ttl);
-       if (result != ISC_R_SUCCESS) {
-               isc_log_write(dns_lctx, DNS_LOGCATEGORY_RESOLVER,
-                             DNS_LOGMODULE_RESOLVER, ISC_LOG_ERROR,
-                             "could not mark server as lame: %s",
-                             isc_result_totext(result));
+       if (fctx->res->lame_ttl != 0) {
+               result = dns_adb_marklame(fctx->adb, query->addrinfo,
+                                         fctx->name, fctx->type,
+                                         rctx->now + fctx->res->lame_ttl);
+               if (result != ISC_R_SUCCESS) {
+                       isc_log_write(dns_lctx, DNS_LOGCATEGORY_RESOLVER,
+                                     DNS_LOGMODULE_RESOLVER, ISC_LOG_ERROR,
+                                     "could not mark server as lame: %s",
+                                     isc_result_totext(result));
+               }
        }
        rctx->broken_server = DNS_R_LAME;
        rctx->next_server = true;