Add hinting to improve ASLR for macos (all allocations) and linux (newly added allocation types).

src/platform-linux.cc

 // Copyright 2011 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 438 matching lines @@
 
 
 OS::MemoryMappedFile* OS::MemoryMappedFile::open(const char* name) {
   FILE* file = fopen(name, "r+");
   if (file == NULL) return NULL;
 
   fseek(file, 0, SEEK_END);
   int size = ftell(file);
 
   void* memory =
-      mmap(0, size, PROT_READ | PROT_WRITE, MAP_SHARED, fileno(file), 0);
+      mmap(GetRandomMmapAddr(), size, PROT_READ | PROT_WRITE,

[Vyacheslav Egorov (Chromium), 2011/10/04 09:18:33]

preferred formatting is one arguments per line

[Cris Neckar, 2011/10/04 19:20:47]

Done.

+           MAP_SHARED, fileno(file), 0);
   return new PosixMemoryMappedFile(file, memory, size);
 }
 
 
 OS::MemoryMappedFile* OS::MemoryMappedFile::create(const char* name, int size,
     void* initial) {
   FILE* file = fopen(name, "w+");
   if (file == NULL) return NULL;
   int result = fwrite(initial, size, 1, file);
   if (result < 1) {
     fclose(file);
     return NULL;
   }
   void* memory =
-      mmap(0, size, PROT_READ | PROT_WRITE, MAP_SHARED, fileno(file), 0);
+      mmap(GetRandomMmapAddr(), size, PROT_READ | PROT_WRITE,

[Vyacheslav Egorov (Chromium), 2011/10/04 09:18:33]

ditto

[Cris Neckar, 2011/10/04 19:20:47]

Done.

+           MAP_SHARED, fileno(file), 0);
   return new PosixMemoryMappedFile(file, memory, size);
 }
 
 
 PosixMemoryMappedFile::~PosixMemoryMappedFile() {
   if (memory_) OS::Free(memory_, size_);
   fclose(file_);
 }
 
 
@@ skipping 64 matching lines @@
   // Support for ll_prof.py.
   //
   // The Linux profiler built into the kernel logs all mmap's with
   // PROT_EXEC so that analysis tools can properly attribute ticks. We
   // do a mmap with a name known by ll_prof.py and immediately munmap
   // it. This injects a GC marker into the stream of events generated
   // by the kernel and allows us to synchronize V8 code log and the
   // kernel log.
   int size = sysconf(_SC_PAGESIZE);
   FILE* f = fopen(kGCFakeMmap, "w+");
-  void* addr = mmap(NULL, size, PROT_READ | PROT_EXEC, MAP_PRIVATE,
-                    fileno(f), 0);
+  void* addr = mmap(GetRandomMmapAddr(), size, PROT_READ | PROT_EXEC,

[Vyacheslav Egorov (Chromium), 2011/10/04 09:18:33]

ditto

[Cris Neckar, 2011/10/04 19:20:47]

Done.

+                    MAP_PRIVATE, fileno(f), 0);
   ASSERT(addr != MAP_FAILED);
   OS::Free(addr, size);
   fclose(f);
 }
 
 
 int OS::StackWalk(Vector<OS::StackFrame> frames) {
   // backtrace is a glibc extension.
 #ifdef __GLIBC__
   int frames_size = frames.length();
@@ skipping 651 matching lines @@
 
 
 void Sampler::Stop() {
   ASSERT(IsActive());
   SignalSender::RemoveActiveSampler(this);
   SetActive(false);
 }
 
 
 } }  // namespace v8::internal