winhttp: Don't allow queueing websocket receive if another is pending.

dlls/winhttp/request.c

@@ -3743,13 +3743,24 @@ DWORD WINAPI WinHttpWebSocketReceive( HINTERNET hsocket, void *buf, DWORD len, D
     {
         struct socket_receive *r;
 
-        if (!(r = malloc( sizeof(*r) ))) return FALSE;
+        if (InterlockedIncrement( &socket->hdr.pending_receives ) > 1)
+        {
+            InterlockedDecrement( &socket->hdr.pending_receives );
+            WARN( "Attempt to queue receive while another is pending.\n" );
+            release_object( &socket->hdr );
+            return ERROR_INVALID_OPERATION;
+        }
+
+        if (!(r = malloc( sizeof(*r) )))
+        {
+            InterlockedDecrement( &socket->hdr.pending_receives );
+            return ERROR_OUTOFMEMORY;
+        }
         r->socket = socket;
         r->buf    = buf;
         r->len    = len;
 
         addref_object( &socket->hdr );
-        InterlockedIncrement( &socket->hdr.pending_receives );
         if ((ret = queue_task( &socket->recv_q, task_socket_receive, r )))
         {
             InterlockedDecrement( &socket->hdr.pending_receives );

dlls/winhttp/tests/notification.c

@@ -1104,6 +1104,8 @@ static void test_websocket(BOOL secure)
 
     err = pWinHttpWebSocketReceive( socket, buffer, sizeof(buffer), &size, &type );
     ok( err == ERROR_SUCCESS, "got %u\n", err );
+    err = pWinHttpWebSocketReceive( socket, buffer, sizeof(buffer), &size, &type );
+    ok( err == ERROR_INVALID_OPERATION, "got %u\n", err );
 
     setup_test( &info, winhttp_websocket_shutdown, __LINE__ );
     ws_status = (WINHTTP_WEB_SOCKET_STATUS *)info.buffer;