projects/fast-dds/patch.diff

diff --git a/src/cpp/CMakeLists.txt b/src/cpp/CMakeLists.txt
index b7fb777..615e955 100644
--- a/src/cpp/CMakeLists.txt
+++ b/src/cpp/CMakeLists.txt
@@ -484,6 +484,11 @@ elseif(NOT EPROSIMA_INSTALLER)
     endif()
 endif()
 
+if(DEFINED ENV{LIB_FUZZING_ENGINE})
+  add_executable(fuzz_processCDRMsg rtps/messages/fuzz_processCDRMsg.cpp)
+  target_link_libraries(fuzz_processCDRMsg ${PROJECT_NAME} $ENV{LIB_FUZZING_ENGINE})
+endif()
+
 ###############################################################################
 # Packaging
 ###############################################################################
diff --git a/src/cpp/rtps/messages/MessageReceiver.cpp b/src/cpp/rtps/messages/MessageReceiver.cpp
index 962ca9b..0e82082 100644
--- a/src/cpp/rtps/messages/MessageReceiver.cpp
+++ b/src/cpp/rtps/messages/MessageReceiver.cpp
@@ -324,7 +324,11 @@ void MessageReceiver::processCDRMsg(
 
     reset();
 
+#ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
+    GuidPrefix_t participantGuidPrefix;
+#else
     GuidPrefix_t participantGuidPrefix = participant_->getGuid().guidPrefix;
+#endif
     dest_guid_prefix_ = participantGuidPrefix;
 
     msg->pos = 0; //Start reading at 0
@@ -513,7 +517,9 @@ void MessageReceiver::processCDRMsg(
         submessage->pos = next_msg_pos;
     }
 
+#ifndef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
     participant_->assert_remote_participant_liveliness(source_guid_prefix_);
+#endif
 }
 
 bool MessageReceiver::checkRTPSHeader(
diff --git a/src/cpp/rtps/messages/fuzz_processCDRMsg.cpp b/src/cpp/rtps/messages/fuzz_processCDRMsg.cpp
new file mode 100644
index 0000000..6a71817
--- /dev/null
+++ b/src/cpp/rtps/messages/fuzz_processCDRMsg.cpp
@@ -0,0 +1,26 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <stdarg.h>
+#include <string.h>
+
+#include <fastrtps/rtps/messages/MessageReceiver.h>
+#include <fastdds/rtps/attributes/RTPSParticipantAttributes.h>
+
+extern "C" int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
+    const eprosima::fastrtps::rtps::Locator_t remoteLocator;
+    eprosima::fastrtps::rtps::MessageReceiver* rcv = new eprosima::fastrtps::rtps::MessageReceiver(NULL, 4096);
+
+    eprosima::fastrtps::rtps::CDRMessage_t msg(0);
+    msg.wraps = true;
+    msg.buffer = const_cast<eprosima::fastrtps::rtps::octet*>(data);
+    msg.length = size;
+    msg.max_size = size;
+    msg.reserved_size = size;
+
+    // TODO: Should we unlock in case UnregisterReceiver is called from callback ?
+    rcv->processCDRMsg(remoteLocator, &msg);
+    delete rcv;
+    return 0;
+}
+