1 files changed, 177 insertions, 0 deletions
diff --git a/libsanitizer/asan/asan_allocator.h b/libsanitizer/asan/asan_allocator.h
new file mode 100644
index 00000000000..372ca0635ed
--- /dev/null
+++ b/libsanitizer/asan/asan_allocator.h
@@ -0,0 +1,177 @@
+//===-- asan_allocator.h ----------------------------------------*- C++ -*-===//
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file is a part of AddressSanitizer, an address sanity checker.
+//
+// ASan-private header for asan_allocator.cc.
+//===----------------------------------------------------------------------===//
+
+#ifndef ASAN_ALLOCATOR_H
+#define ASAN_ALLOCATOR_H
+
+#include "asan_internal.h"
+#include "asan_interceptors.h"
+
+namespace __asan {
+
+static const uptr kNumberOfSizeClasses = 255;
+struct AsanChunk;
+
+class AsanChunkView {
+ public:
+  explicit AsanChunkView(AsanChunk *chunk) : chunk_(chunk) {}
+  bool IsValid() { return chunk_ != 0; }
+  uptr Beg();       // first byte of user memory.
+  uptr End();       // last byte of user memory.
+  uptr UsedSize();  // size requested by the user.
+  uptr AllocTid();
+  uptr FreeTid();
+  void GetAllocStack(StackTrace *stack);
+  void GetFreeStack(StackTrace *stack);
+  bool AddrIsInside(uptr addr, uptr access_size, uptr *offset);
+  bool AddrIsAtLeft(uptr addr, uptr access_size, uptr *offset);
+  bool AddrIsAtRight(uptr addr, uptr access_size, uptr *offset);
+ private:
+  AsanChunk *const chunk_;
+};
+
+AsanChunkView FindHeapChunkByAddress(uptr address);
+
+class AsanChunkFifoList {
+ public:
+  explicit AsanChunkFifoList(LinkerInitialized) { }
+  AsanChunkFifoList() { clear(); }
+  void Push(AsanChunk *n);
+  void PushList(AsanChunkFifoList *q);
+  AsanChunk *Pop();
+  uptr size() { return size_; }
+  void clear() {
+    first_ = last_ = 0;
+    size_ = 0;
+  }
+ private:
+  AsanChunk *first_;
+  AsanChunk *last_;
+  uptr size_;
+};
+
+struct AsanThreadLocalMallocStorage {
+  explicit AsanThreadLocalMallocStorage(LinkerInitialized x)
+      : quarantine_(x) { }
+  AsanThreadLocalMallocStorage() {
+    CHECK(REAL(memset));
+    REAL(memset)(this, 0, sizeof(AsanThreadLocalMallocStorage));
+  }
+
+  AsanChunkFifoList quarantine_;
+  AsanChunk *free_lists_[kNumberOfSizeClasses];
+  void CommitBack();
+};
+
+// Fake stack frame contains local variables of one function.
+// This struct should fit into a stack redzone (32 bytes).
+struct FakeFrame {
+  uptr magic;  // Modified by the instrumented code.
+  uptr descr;  // Modified by the instrumented code.
+  FakeFrame *next;
+  u64 real_stack     : 48;
+  u64 size_minus_one : 16;
+};
+
+struct FakeFrameFifo {
+ public:
+  void FifoPush(FakeFrame *node);
+  FakeFrame *FifoPop();
+ private:
+  FakeFrame *first_, *last_;
+};
+
+class FakeFrameLifo {
+ public:
+  void LifoPush(FakeFrame *node) {
+    node->next = top_;
+    top_ = node;
+  }
+  void LifoPop() {
+    CHECK(top_);
+    top_ = top_->next;
+  }
+  FakeFrame *top() { return top_; }
+ private:
+  FakeFrame *top_;
+};
+
+// For each thread we create a fake stack and place stack objects on this fake
+// stack instead of the real stack. The fake stack is not really a stack but
+// a fast malloc-like allocator so that when a function exits the fake stack
+// is not poped but remains there for quite some time until gets used again.
+// So, we poison the objects on the fake stack when function returns.
+// It helps us find use-after-return bugs.
+// We can not rely on __asan_stack_free being called on every function exit,
+// so we maintain a lifo list of all current fake frames and update it on every
+// call to __asan_stack_malloc.
+class FakeStack {
+ public:
+  FakeStack();
+  explicit FakeStack(LinkerInitialized) {}
+  void Init(uptr stack_size);
+  void StopUsingFakeStack() { alive_ = false; }
+  void Cleanup();
+  uptr AllocateStack(uptr size, uptr real_stack);
+  static void OnFree(uptr ptr, uptr size, uptr real_stack);
+  // Return the bottom of the maped region.
+  uptr AddrIsInFakeStack(uptr addr);
+  bool StackSize() { return stack_size_; }
+
+ private:
+  static const uptr kMinStackFrameSizeLog = 9;  // Min frame is 512B.
+  static const uptr kMaxStackFrameSizeLog = 16;  // Max stack frame is 64K.
+  static const uptr kMaxStackMallocSize = 1 << kMaxStackFrameSizeLog;
+  static const uptr kNumberOfSizeClasses =
+      kMaxStackFrameSizeLog - kMinStackFrameSizeLog + 1;
+
+  bool AddrIsInSizeClass(uptr addr, uptr size_class);
+
+  // Each size class should be large enough to hold all frames.
+  uptr ClassMmapSize(uptr size_class);
+
+  uptr ClassSize(uptr size_class) {
+    return 1UL << (size_class + kMinStackFrameSizeLog);
+  }
+
+  void DeallocateFrame(FakeFrame *fake_frame);
+
+  uptr ComputeSizeClass(uptr alloc_size);
+  void AllocateOneSizeClass(uptr size_class);
+
+  uptr stack_size_;
+  bool   alive_;
+
+  uptr allocated_size_classes_[kNumberOfSizeClasses];
+  FakeFrameFifo size_classes_[kNumberOfSizeClasses];
+  FakeFrameLifo call_stack_;
+};
+
+void *asan_memalign(uptr alignment, uptr size, StackTrace *stack);
+void asan_free(void *ptr, StackTrace *stack);
+
+void *asan_malloc(uptr size, StackTrace *stack);
+void *asan_calloc(uptr nmemb, uptr size, StackTrace *stack);
+void *asan_realloc(void *p, uptr size, StackTrace *stack);
+void *asan_valloc(uptr size, StackTrace *stack);
+void *asan_pvalloc(uptr size, StackTrace *stack);
+
+int asan_posix_memalign(void **memptr, uptr alignment, uptr size,
+                          StackTrace *stack);
+uptr asan_malloc_usable_size(void *ptr, StackTrace *stack);
+
+uptr asan_mz_size(const void *ptr);
+void asan_mz_force_lock();
+void asan_mz_force_unlock();
+
+}  // namespace __asan
+#endif  // ASAN_ALLOCATOR_H