Buffer undecryptable QUIC packets in the Dispatcher when doing cheap stateless rejects.

net/tools/quic/quic_dispatcher_test.cc

Index: net/tools/quic/quic_dispatcher_test.cc
diff --git a/net/tools/quic/quic_dispatcher_test.cc b/net/tools/quic/quic_dispatcher_test.cc
index a063a2daf66da169b2b1417a5745b81af66ce71d..51521daff7b12290cc1403f273093504f5c80ac3 100644
--- a/net/tools/quic/quic_dispatcher_test.cc
+++ b/net/tools/quic/quic_dispatcher_test.cc
@@ -660,6 +660,51 @@ TEST_P(QuicDispatcherStatelessRejectTest, CheapRejects) {
   }
 }
 
+TEST_P(QuicDispatcherStatelessRejectTest, BufferNonChlo) {
+  FLAGS_quic_use_cheap_stateless_rejects = true;
+  CreateTimeWaitListManager();
+
+  const IPEndPoint client_address(net::test::Loopback4(), 1);
+  const QuicConnectionId connection_id = 1;
+
+  if (!GetParam().enable_stateless_rejects_via_flag) {
+    // If stateless rejects are not being used, then a connection will be
+    // created immediately.
+    EXPECT_CALL(dispatcher_, CreateQuicSession(connection_id, client_address))
+        .WillOnce(testing::Return(
+            CreateSessionBasedOnTestParams(connection_id, client_address)));
+  }
+  ProcessPacket(client_address, connection_id, true, false,
+                "NOT DATA FOR A CHLO");
+
+  // Process the first packet for the connection.
+  // clang-format off
+  CryptoHandshakeMessage client_hello = CryptoTestUtils::Message(
+      "CHLO",
+      "AEAD", "AESG",
+      "KEXS", "C255",
+      "NONC", "1234567890123456789012",
+      "VER\0", "Q025",
+      "$padding", static_cast<int>(kClientHelloMinimumSize),
+      nullptr);
+  // clang-format on
+
+  if (GetParam().enable_stateless_rejects_via_flag) {
+    // If stateless rejects are enabled then a connection will be created now
+    // and the buffered packet will be processed
+    EXPECT_CALL(dispatcher_, CreateQuicSession(connection_id, client_address))
+        .WillOnce(testing::Return(
+            CreateSessionBasedOnTestParams(connection_id, client_address)));
+  }
+  EXPECT_CALL(*reinterpret_cast<MockQuicConnection*>(session1_->connection()),
+              ProcessUdpPacket(_, client_address, _))
+      .RetiresOnSaturation();
+  ProcessPacket(client_address, connection_id, true, false,
+                client_hello.GetSerialized().AsStringPiece().as_string());
+  EXPECT_FALSE(
+      time_wait_list_manager_->IsConnectionIdInTimeWait(connection_id));
+}
+
 // Verify the stopgap test: Packets with truncated connection IDs should be
 // dropped.
 class QuicDispatcherTestStrayPacketConnectionId : public QuicDispatcherTest {};