Simple RTCP receiver fuzzer.

Doesn't utilize the clock or any callbacks out of the receiver but
should still be useful to test input packet parsing.

BUG=webrtc:4771
R=danilchap@webrtc.org

Review URL: https://codereview.webrtc.org/1716143002 .

Cr-Commit-Position: refs/heads/master@{#11717}

webrtc/test/fuzzers/BUILD.gn

@@ -66,6 +66,15 @@ webrtc_fuzzer_test("producer_fec_fuzzer") {
   ]
 }
 
+webrtc_fuzzer_test("rtcp_receiver_fuzzer") {
+  sources = [
+    "rtcp_receiver_fuzzer.cc",
+  ]
+  deps = [
+    "../../modules/rtp_rtcp/",
+  ]
+}
+
 source_set("audio_decoder_fuzzer") {
   public_configs = [ "../..:common_inherited_config" ]
   sources = [

webrtc/test/fuzzers/rtcp_receiver_fuzzer.cc

@@ -0,0 +1,30 @@
+/*
+ *  Copyright (c) 2015 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+#include "webrtc/base/checks.h"
+#include "webrtc/base/scoped_ptr.h"
+#include "webrtc/modules/rtp_rtcp/source/rtcp_receiver.h"
+#include "webrtc/system_wrappers/include/clock.h"
+
+namespace webrtc {
+
+void FuzzOneInput(const uint8_t* data, size_t size) {
+  RTCPUtility::RTCPParserV2 rtcp_parser(data, size, true);
+  if (!rtcp_parser.IsValid())
+    return;
+
+  webrtc::SimulatedClock clock(1234);
+  RTCPReceiver receiver(&clock, false, nullptr, nullptr, nullptr, nullptr,
+                        nullptr);
+
+  RTCPHelp::RTCPPacketInformation rtcp_packet_information;
+  receiver.IncomingRTCPPacket(rtcp_packet_information, &rtcp_parser);
+}
+}  // namespace webrtc
+