fctx_finddone: call fctx_destroy within the bucket lock

diff --git a/CHANGES b/CHANGES
index e8537c9f6cd31859decc225453b557e196315356..f11c7815cb9a97af587ecd8bf1f7b682356cf692 100644 (file)
--- a/CHANGES
+++ b/CHANGES
@@ -1,7 +1,11 @@
+3309.  [bug]           resolver.c:fctx_finddone() was not threadsafe.
+                       [RT #27995]
+
 3307.  [bug]           Add missing ISC_LANG_BEGINDECLS and ISC_LANG_ENDDECLS.
                        [RT #28956]
 
-3304.  [bug]           Use hmctx, not mctx when freeing rbtdb->heaps. [RT #28571]
+3304.  [bug]           Use hmctx, not mctx when freeing rbtdb->heaps.
+                       [RT #28571]
 
 3301.  [contrib]       Update queryperf to build on darwin.  Add -R flag
                        for non-recursive queries. [RT #28565]

diff --git a/lib/dns/resolver.c b/lib/dns/resolver.c
index 105ed6130e40ad5766d1c25771660a401654d314..48029d11cebea33665da3f4a0c6fc4f61eae039c 100644 (file)
--- a/lib/dns/resolver.c
+++ b/lib/dns/resolver.c
@@ -2156,7 +2156,6 @@ fctx_finddone(isc_task_t *task, isc_event_t *event) {
        isc_boolean_t want_try = ISC_FALSE;
        isc_boolean_t want_done = ISC_FALSE;
        isc_boolean_t bucket_empty = ISC_FALSE;
-       isc_boolean_t destroy = ISC_FALSE;
        unsigned int bucketnum;
 
        find = event->ev_sender;
@@ -2195,17 +2194,12 @@ fctx_finddone(isc_task_t *task, isc_event_t *event) {
                }
        } else if (SHUTTINGDOWN(fctx) && fctx->pending == 0 &&
                   fctx->nqueries == 0 && ISC_LIST_EMPTY(fctx->validators)) {
-               /*
-                * Note that we had to wait until we had the lock before
-                * looking at fctx->references.
-                */
+
                if (fctx->references == 0)
-                       destroy = ISC_TRUE;
+                       bucket_empty = fctx_destroy(fctx);
        }
        UNLOCK(&res->buckets[bucketnum].lock);
 
-       if (destroy)
-               bucket_empty = fctx_destroy(fctx);
        isc_event_free(&event);
        dns_adb_destroyfind(&find);