[mojo-edk] Add some buffer checks and fix UAF on NodeChannel

mojo/edk/system/data_pipe_consumer_dispatcher.cc

Index: mojo/edk/system/data_pipe_consumer_dispatcher.cc
diff --git a/mojo/edk/system/data_pipe_consumer_dispatcher.cc b/mojo/edk/system/data_pipe_consumer_dispatcher.cc
index 7bf0b0177acdbd0a2a86891d6f6473cbbfab6752..158b0e17e3ed6ac9c80c5704043e10d469dae993 100644
--- a/mojo/edk/system/data_pipe_consumer_dispatcher.cc
+++ b/mojo/edk/system/data_pipe_consumer_dispatcher.cc
@@ -535,6 +535,11 @@ void DataPipeConsumerDispatcher::UpdateSignalsStateNoLock() {
       if (rv != ports::OK)
         peer_closed_ = true;
       if (message) {
+        if (message->num_payload_bytes() < sizeof(DataPipeControlMessage)) {
+          peer_closed_ = true;
+          break;
+        }
+
         const DataPipeControlMessage* m =
             static_cast<const DataPipeControlMessage*>(
                 message->payload_bytes());