TCMalloc: restrict maximum size of memory ranges

third_party/tcmalloc/chromium/src/common.h

 // Copyright (c) 2008, Google Inc.
 // 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
@@ skipping 126 matching lines @@
 
 namespace tcmalloc {
 
 // Convert byte size into pages.  This won't overflow, but may return
 // an unreasonably large value if bytes is huge enough.
 inline Length pages(size_t bytes) {
   return (bytes >> kPageShift) +
       ((bytes & (kPageSize - 1)) > 0 ? 1 : 0);
 }
 
+// For security reasons, we want to limit the size of allocations.
+// See crbug.com/169327.
+bool IsAllocSizePermitted(size_t alloc_size);

[Chris Evans, 2013/01/15 01:53:08]

Mark it inline. Any maybe have the implementation inline too? It's no larger
than the pages() function above.

[jln (very slow on Chromium), 2013/01/15 02:00:51]

Let me know how strongly you feel about it. Since it does straddle compilation
units, if we really want it inline, we should put the implementation in the
header.

I don't feel strongly either way.

+
 // For larger allocation sizes, we use larger memory alignments to
 // reduce the number of size classes.
 int AlignmentForSize(size_t size);
 
 // Size-class information + mapping
 class SizeMap {
  private:
   // Number of objects to move between a per-thread list and a central
   // list in one shot.  We want this to be not too small so we can
   // amortize the lock overhead for accessing the central list.  Making
@@ skipping 103 matching lines @@
 static const int kMaxStackDepth = 31;
 struct StackTrace {
   uintptr_t size;          // Size of object
   uintptr_t depth;         // Number of PC values stored in array below
   void*     stack[kMaxStackDepth];
 };
 
 }  // namespace tcmalloc
 
 #endif  // TCMALLOC_COMMON_H_