Node: fix status memory leak, improve tcp_uv read buffer allocation code

src/core/lib/iomgr/tcp_uv.c

@@ -80,6 +80,7 @@ typedef struct {
 } grpc_tcp;
 
 static void tcp_free(grpc_exec_ctx *exec_ctx, grpc_tcp *tcp) {
+  grpc_slice_unref(tcp->read_slice);
   grpc_resource_user_unref(exec_ctx, tcp->resource_user);
   gpr_free(tcp);
 }
@@ -125,13 +126,17 @@ static void uv_close_callback(uv_handle_t *handle) {
   grpc_exec_ctx_finish(&exec_ctx);
 }
 
+static grpc_slice alloc_read_slice(grpc_exec_ctx *exec_ctx,
+                                   grpc_resource_user *resource_user) {
+  return grpc_resource_user_slice_malloc(exec_ctx, resource_user,
+                                         GRPC_TCP_DEFAULT_READ_SLICE_SIZE);
+}
+
 static void alloc_uv_buf(uv_handle_t *handle, size_t suggested_size,
                          uv_buf_t *buf) {
   grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
   grpc_tcp *tcp = handle->data;
   (void)suggested_size;
-  tcp->read_slice = grpc_resource_user_slice_malloc(
-      &exec_ctx, tcp->resource_user, GRPC_TCP_DEFAULT_READ_SLICE_SIZE);
   buf->base = (char *)GRPC_SLICE_START_PTR(tcp->read_slice);
   buf->len = GRPC_SLICE_LENGTH(tcp->read_slice);
   grpc_exec_ctx_finish(&exec_ctx);
@@ -158,6 +163,7 @@ static void read_callback(uv_stream_t *stream, ssize_t nread,
     // Successful read
     sub = grpc_slice_sub_no_ref(tcp->read_slice, 0, (size_t)nread);
     grpc_slice_buffer_add(tcp->read_slices, sub);
+    tcp->read_slice = alloc_read_slice(&exec_ctx, tcp->resource_user);
     error = GRPC_ERROR_NONE;
     if (GRPC_TRACER_ON(grpc_tcp_trace)) {
       size_t i;
@@ -347,6 +353,7 @@ grpc_endpoint *grpc_tcp_create(uv_tcp_t *handle,
                                grpc_resource_quota *resource_quota,
                                char *peer_string) {
   grpc_tcp *tcp = (grpc_tcp *)gpr_malloc(sizeof(grpc_tcp));
+  grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
 
   if (GRPC_TRACER_ON(grpc_tcp_trace)) {
     gpr_log(GPR_DEBUG, "Creating TCP endpoint %p", tcp);
@@ -363,6 +370,7 @@ grpc_endpoint *grpc_tcp_create(uv_tcp_t *handle,
   tcp->peer_string = gpr_strdup(peer_string);
   tcp->shutting_down = false;
   tcp->resource_user = grpc_resource_user_create(resource_quota, peer_string);
+  tcp->read_slice = alloc_read_slice(&exec_ctx, tcp->resource_user);
   /* Tell network status tracking code about the new endpoint */
   grpc_network_status_register_endpoint(&tcp->base);
 
@@ -370,6 +378,8 @@ grpc_endpoint *grpc_tcp_create(uv_tcp_t *handle,
   uv_unref((uv_handle_t *)handle);
 #endif
 
+  grpc_exec_ctx_finish(&exec_ctx);
+
   return &tcp->base;
 }
 

src/node/ext/call.cc

@@ -398,7 +398,10 @@ class ClientStatusOp : public Op {
  public:
   ClientStatusOp() { grpc_metadata_array_init(&metadata_array); }
 
-  ~ClientStatusOp() { grpc_metadata_array_destroy(&metadata_array); }
+  ~ClientStatusOp() {
+    grpc_metadata_array_destroy(&metadata_array);
+    grpc_slice_unref(status_details);
+  }
 
   bool ParseOp(Local<Value> value, grpc_op *out) {
     out->data.recv_status_on_client.trailing_metadata = &metadata_array;