Fix a crash due to use-after-free (#38495)

CHANGES

@@ -1,3 +1,6 @@
+4087.	[bug]		Fix a crash due to use-after-free due to sequencing
+			of tasks actions. [RT #38495]
+
 4086.	[bug]		Fix out-of-srcdir build with native pkcs11. [RT #38831]
 
 4085.	[bug]		ISC_PLATFORM_HAVEXADDQ could be inconsistently set.

lib/dns/adb.c

@@ -1519,6 +1519,7 @@ clean_finds_at_name(dns_adbname_t *name, isc_eventtype_t evtype,
 			   ev, task, find);
 
 			isc_task_sendanddetach(&task, (isc_event_t **)&ev);
+			find->flags |= FIND_EVENT_SENT;
 		} else {
 			DP(DEF_LEVEL, "cfan: skipping find %p", find);
 		}

lib/dns/zone.c

@@ -10206,9 +10206,6 @@ static void
 notify_destroy(dns_notify_t *notify, isc_boolean_t locked) {
 	isc_mem_t *mctx;
 
-	/*
-	 * Caller holds zone lock.
-	 */
 	REQUIRE(DNS_NOTIFY_VALID(notify));
 
 	if (notify->zone != NULL) {