Add refcounts for async callbacks in auth and client filters.

src/core/ext/filters/client_channel/client_channel.cc

@@ -1095,6 +1095,7 @@ static void pick_callback_done_locked(void* arg, grpc_error* error) {
             chand, calld);
   }
   async_pick_done_locked(elem, GRPC_ERROR_REF(error));
+  GRPC_CALL_STACK_UNREF(calld->owning_call, "pick_callback");
 }
 
 // Takes a ref to chand->lb_policy and calls grpc_lb_policy_pick_locked().
@@ -1134,6 +1135,7 @@ static bool pick_callback_start_locked(grpc_call_element* elem) {
   GRPC_CLOSURE_INIT(&calld->lb_pick_closure, pick_callback_done_locked, elem,
                     grpc_combiner_scheduler(chand->combiner));
   calld->pick.on_complete = &calld->lb_pick_closure;
+  GRPC_CALL_STACK_REF(calld->owning_call, "pick_callback");
   const bool pick_done =
       grpc_lb_policy_pick_locked(chand->lb_policy, &calld->pick);
   if (pick_done) {
@@ -1142,6 +1144,7 @@ static bool pick_callback_start_locked(grpc_call_element* elem) {
       gpr_log(GPR_DEBUG, "chand=%p calld=%p: pick completed synchronously",
               chand, calld);
     }
+    GRPC_CALL_STACK_UNREF(calld->owning_call, "pick_callback");
   } else {
     GRPC_CALL_STACK_REF(calld->owning_call, "pick_callback_cancel");
     grpc_call_combiner_set_notify_on_cancel(

src/core/lib/security/transport/client_auth_filter.cc

@@ -118,6 +118,7 @@ static void on_credentials_metadata(void* arg, grpc_error* input_error) {
     grpc_transport_stream_op_batch_finish_with_failure(batch, error,
                                                        calld->call_combiner);
   }
+  GRPC_CALL_STACK_UNREF(calld->owning_call, "get_request_metadata");
 }
 
 void grpc_auth_metadata_context_build(
@@ -208,7 +209,7 @@ static void send_security_metadata(grpc_call_element* elem,
       chand->auth_context, &calld->auth_md_context);
 
   GPR_ASSERT(calld->pollent != nullptr);
-
+  GRPC_CALL_STACK_REF(calld->owning_call, "get_request_metadata");
   GRPC_CLOSURE_INIT(&calld->async_result_closure, on_credentials_metadata,
                     batch, grpc_schedule_on_exec_ctx);
   grpc_error* error = GRPC_ERROR_NONE;
@@ -250,6 +251,7 @@ static void on_host_checked(void* arg, grpc_error* error) {
         calld->call_combiner);
     gpr_free(error_msg);
   }
+  GRPC_CALL_STACK_UNREF(calld->owning_call, "check_call_host");
 }
 
 static void cancel_check_call_host(void* arg, grpc_error* error) {
@@ -312,6 +314,7 @@ static void auth_start_transport_stream_op_batch(
     }
     if (calld->have_host) {
       batch->handler_private.extra_arg = elem;
+      GRPC_CALL_STACK_REF(calld->owning_call, "check_call_host");
       GRPC_CLOSURE_INIT(&calld->async_result_closure, on_host_checked, batch,
                         grpc_schedule_on_exec_ctx);
       char* call_host = grpc_slice_to_c_string(calld->host);