Fix memory leak on disconnection

src/core/ext/client_config/client_channel.c

@@ -205,7 +205,11 @@ static void cc_on_config_changed(grpc_exec_ctx *exec_ctx, void *arg,
   gpr_mu_lock(&chand->mu_config);
   old_lb_policy = chand->lb_policy;
   chand->lb_policy = lb_policy;
-  if (lb_policy != NULL || chand->resolver == NULL /* disconnected */) {
+  if (lb_policy != NULL) {
+    grpc_exec_ctx_enqueue_list(exec_ctx, &chand->waiting_for_config_closures,
+                               NULL);
+  } else if (chand->resolver == NULL /* disconnected */) {
+    grpc_closure_list_fail_all(&chand->waiting_for_config_closures);
     grpc_exec_ctx_enqueue_list(exec_ctx, &chand->waiting_for_config_closures,
                                NULL);
   }
@@ -321,10 +325,10 @@ static int cc_pick_subchannel(grpc_exec_ctx *exec_ctx, void *arg,
 
 static void continue_picking(grpc_exec_ctx *exec_ctx, void *arg, bool success) {
   continue_picking_args *cpa = arg;
-  if (!success) {
-    grpc_exec_ctx_enqueue(exec_ctx, cpa->on_ready, false, NULL);
-  } else if (cpa->connected_subchannel == NULL) {
+  if (cpa->connected_subchannel == NULL) {
     /* cancelled, do nothing */
+  } else if (!success) {
+    grpc_exec_ctx_enqueue(exec_ctx, cpa->on_ready, false, NULL);
   } else if (cc_pick_subchannel(exec_ctx, cpa->elem, cpa->initial_metadata,
                                 cpa->initial_metadata_flags,
                                 cpa->connected_subchannel, cpa->on_ready)) {

src/core/lib/iomgr/closure.c

@@ -54,6 +54,12 @@ void grpc_closure_list_add(grpc_closure_list *closure_list,
   closure_list->tail = closure;
 }
 
+void grpc_closure_list_fail_all(grpc_closure_list *list) {
+  for (grpc_closure *c = list->head; c != NULL; c = grpc_closure_next(c)) {
+    c->final_data &= ~(uintptr_t)1;
+  }
+}
+
 bool grpc_closure_list_empty(grpc_closure_list closure_list) {
   return closure_list.head == NULL;
 }

src/core/lib/iomgr/closure.h

@@ -86,6 +86,9 @@ grpc_closure *grpc_closure_create(grpc_iomgr_cb_func cb, void *cb_arg);
 void grpc_closure_list_add(grpc_closure_list *list, grpc_closure *closure,
                            bool success);
 
+/** force all success bits in \a list to false */
+void grpc_closure_list_fail_all(grpc_closure_list *list);
+
 /** append all closures from \a src to \a dst and empty \a src. */
 void grpc_closure_list_move(grpc_closure_list *src, grpc_closure_list *dst);
 

src/core/lib/iomgr/exec_ctx.h

@@ -92,6 +92,8 @@ void grpc_exec_ctx_enqueue_list(grpc_exec_ctx *exec_ctx,
                                 grpc_closure_list *list,
                                 grpc_workqueue *offload_target_or_null);
 
+void grpc_exec_ctx_global_init(void);
+
 void grpc_exec_ctx_global_init(void);
 void grpc_exec_ctx_global_shutdown(void);