handler/mac: Log a warning when an exception message has a suspicious

util/mach/exception_ports_test.cc

 // Copyright 2014 The Crashpad Authors. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
 // You may obtain a copy of the License at
 //
 //     http://www.apache.org/licenses/LICENSE-2.0
 //
 // Unless required by applicable law or agreed to in writing, software
 // distributed under the License is distributed on an "AS IS" BASIS,
@@ skipping 179 matching lines @@
     if (exception == EXC_CRASH && code_count >= 1) {
       int signal;
       ExcCrashRecoverOriginalException(code[0], nullptr, &signal);
 
       // The child crashed with __builtin_trap(), which shows up as SIGILL.
       EXPECT_EQ(SIGILL, signal);
 
       SetExpectedChildTermination(kTerminationSignal, signal);
     }
 
+    EXPECT_EQ(0, AuditPIDFromMachMessageTrailer(trailer));
+
     return ExcServerSuccessfulReturnValue(behavior, false);
   }
 
  private:
   class Child {
    public:
     explicit Child(TestExceptionPorts* test_exception_ports)
         : test_exception_ports_(test_exception_ports),
           thread_(),
           init_semaphore_(0),
@@ skipping 223 matching lines @@
 
     // Let the child process know that everything in the parent process is set
     // up.
     c = '\0';
     CheckedWriteFile(WritePipeHandle(), &c, 1);
 
     if (who_crashes_ != kNobodyCrashes) {
       UniversalMachExcServer universal_mach_exc_server(this);
 
       const mach_msg_timeout_t kTimeoutMs = 50;
-      kern_return_t kr =
-          MachMessageServer::Run(&universal_mach_exc_server,
-                                 local_port,
-                                 MACH_MSG_OPTION_NONE,
-                                 MachMessageServer::kOneShot,
-                                 MachMessageServer::kReceiveLargeError,
-                                 kTimeoutMs);
+      kern_return_t kr = MachMessageServer::Run(
+          &universal_mach_exc_server,
+          local_port,
+          MACH_RCV_TRAILER_TYPE(MACH_MSG_TRAILER_FORMAT_0) |
+              MACH_RCV_TRAILER_ELEMENTS(MACH_RCV_TRAILER_AUDIT),
+          MachMessageServer::kOneShot,
+          MachMessageServer::kReceiveLargeError,
+          kTimeoutMs);
       EXPECT_EQ(KERN_SUCCESS, kr)
           << MachErrorMessage(kr, "MachMessageServer::Run");
 
       EXPECT_TRUE(handled_);
     }
 
     // Wait for the child process to exit or terminate, as indicated by it
     // closing its pipe. This keeps LocalPort() alive in the child as
     // RemotePort(), for the child’s use in its TestGetExceptionPorts().
     CheckedReadFileAtEOF(ReadPipeHandle());
@@ skipping 144 matching lines @@
   if (geteuid() == 0) {
     EXPECT_TRUE(rv);
   } else {
     EXPECT_FALSE(rv);
   }
 }
 
 }  // namespace
 }  // namespace test
 }  // namespace crashpad