Pass Mach message trailers to server handler functions

util/mach/mach_message_server.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 93 matching lines @@
   }
 
   if (receive_large == kReceiveLargeResize) {
     options |= MACH_RCV_LARGE;
   } else {
     options &= ~MACH_RCV_LARGE;
   }
 
   mach_msg_size_t trailer_alloc = REQUESTED_TRAILER_SIZE(options);
   mach_msg_size_t max_request_size = interface->MachMessageServerRequestSize();
-  mach_msg_size_t request_alloc = round_page(max_request_size + trailer_alloc);
+  mach_msg_size_t request_alloc =
+      round_page(round_msg(max_request_size) + trailer_alloc);
 
   // mach_msg_server() and mach_msg_server_once() invert this condition, but
   // their interpretation is incorrect. When it is desirable to retry a receive
   // attempt that returns MACH_RCV_TOO_LARGE with a larger receive buffer, it is
   // also desirable to use the full receive buffer rounded up to a page size for
   // the initial receive attempt. On the other hand, when this behavior is not
   // requested, there is no reason to attempt receiving messages any larger than
   // expected.
-  mach_msg_size_t request_size = (receive_large == kReceiveLargeResize)
-                                     ? max_request_size + trailer_alloc
-                                     : request_alloc;
+  mach_msg_size_t request_size =
+      (receive_large == kReceiveLargeResize)
+          ? round_msg(max_request_size) + trailer_alloc
+          : request_alloc;
 
   mach_msg_size_t max_reply_size = interface->MachMessageServerReplySize();
 
   // mach_msg_server() and mach_msg_server_once() would consider whether
   // |options| contains MACH_SEND_TRAILER and include MAX_TRAILER_SIZE in this
   // computation if it does, but that option is ineffective on OS X.
   mach_msg_size_t reply_alloc = round_page(max_reply_size);
 
   kern_return_t kr;
 
@@ skipping 43 matching lines @@
         } else if (kr == MACH_RCV_INTERRUPTED) {
           run_mach_msg_receive = true;
         }
       } while (run_mach_msg_receive);
 
       if (kr == MACH_MSG_SUCCESS) {
         request_scoper.swap(trial_request_scoper);
       } else if (kr == MACH_RCV_TOO_LARGE &&
                  receive_large == kReceiveLargeResize) {
         this_request_size =
-            round_page(request_header->msgh_size + trailer_alloc);
+            round_page(round_msg(request_header->msgh_size) + trailer_alloc);
         this_request_alloc = this_request_size;
       } else {
         return kr;
       }
     }
 
     vm_address_t reply_addr;
     kr = vm_allocate(mach_task_self(),
                      &reply_addr,
                      reply_alloc,
@@ skipping 84 matching lines @@
         // persistent mode, and just return success when not in persistent mode.
         return (persistent == kPersistent) ? MACH_RCV_TIMED_OUT : kr;
       }
     }
   } while (persistent == kPersistent);
 
   return kr;
 }
 
 }  // namespace crashpad