increment fctx references while waiting for validator

We need to ensure the fctx isn't freed while the validator
is pending.

diff --git a/lib/dns/resolver.c b/lib/dns/resolver.c
index 02c09aad34437794b9d313014e1550a57f64b3e5..828f732c47460713d4178988d562df57def7eaa3 100644 (file)
--- a/lib/dns/resolver.c
+++ b/lib/dns/resolver.c
@@ -916,6 +916,7 @@ valcreate(fetchctx_t *fctx, dns_message_t *message, dns_adbaddrinfo_t *addrinfo,
                        INSIST(fctx->validator == NULL);
                        fctx->validator = validator;
                }
+               fctx_increference(fctx);
                ISC_LIST_APPEND(fctx->validators, validator, link);
        } else {
                dns_message_detach(&valarg->message);
@@ -5222,6 +5223,8 @@ validated(isc_task_t *task, isc_event_t *event) {
        LOCK(&res->buckets[bucketnum].lock);
        sentresponse = ((fctx->options & DNS_FETCHOPT_NOVALIDATE) != 0);
 
+       RUNTIME_CHECK(!fctx_decreference(fctx));
+
        /*
         * If shutting down, ignore the results.  Check to see if we're
         * done waiting for validator completions and ADB pending
@@ -5334,8 +5337,10 @@ validated(isc_task_t *task, isc_event_t *event) {
                result = fctx->vresult;
                add_bad(fctx, message, addrinfo, result, badns_validation);
                isc_event_free(&event);
+
                UNLOCK(&res->buckets[bucketnum].lock);
                INSIST(fctx->validator == NULL);
+
                fctx->validator = ISC_LIST_HEAD(fctx->validators);
                if (fctx->validator != NULL) {
                        dns_validator_send(fctx->validator);