compiler-rt/lib/hwasan/hwasan_mapping.h

   1 //===-- hwasan_mapping.h ----------------------------------------*- C++ -*-===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8 ///
   9 /// \file
  10 /// This file is a part of HWAddressSanitizer and defines memory mapping.
  11 ///
  12 //===----------------------------------------------------------------------===//
  13
  14 #ifndef HWASAN_MAPPING_H
  15 #define HWASAN_MAPPING_H
  16
  17 #include "sanitizer_common/sanitizer_internal_defs.h"
  18 #include "hwasan_interface_internal.h"
  19
  20 // Typical mapping on Linux/x86_64:
  21 // with dynamic shadow mapped at [0x770d59f40000, 0x7f0d59f40000]:
  22 // || [0x7f0d59f40000, 0x7fffffffffff] || HighMem    ||
  23 // || [0x7efe2f934000, 0x7f0d59f3ffff] || HighShadow ||
  24 // || [0x7e7e2f934000, 0x7efe2f933fff] || ShadowGap  ||
  25 // || [0x770d59f40000, 0x7e7e2f933fff] || LowShadow  ||
  26 // || [0x000000000000, 0x770d59f3ffff] || LowMem     ||
  27
  28 // Typical mapping on Android/AArch64
  29 // with dynamic shadow mapped: [0x007477480000, 0x007c77480000]:
  30 // || [0x007c77480000, 0x007fffffffff] || HighMem    ||
  31 // || [0x007c3ebc8000, 0x007c7747ffff] || HighShadow ||
  32 // || [0x007bbebc8000, 0x007c3ebc7fff] || ShadowGap  ||
  33 // || [0x007477480000, 0x007bbebc7fff] || LowShadow  ||
  34 // || [0x000000000000, 0x00747747ffff] || LowMem     ||
  35
  36 // Reasonable values are 4 (for 1/16th shadow) and 6 (for 1/64th).
  37 constexpr uptr kShadowScale = 4;
  38 constexpr uptr kShadowAlignment = 1ULL << kShadowScale;
  39
  40 namespace __hwasan {
  41
  42 extern uptr kLowMemStart;
  43 extern uptr kLowMemEnd;
  44 extern uptr kLowShadowEnd;
  45 extern uptr kLowShadowStart;
  46 extern uptr kHighShadowStart;
  47 extern uptr kHighShadowEnd;
  48 extern uptr kHighMemStart;
  49 extern uptr kHighMemEnd;
  50
  51 inline uptr GetShadowOffset() {
  52   return SANITIZER_FUCHSIA ? 0 : __hwasan_shadow_memory_dynamic_address;
  53 }
  54 inline uptr MemToShadow(uptr untagged_addr) {
  55   return (untagged_addr >> kShadowScale) + GetShadowOffset();
  56 }
  57 inline uptr ShadowToMem(uptr shadow_addr) {
  58   return (shadow_addr - GetShadowOffset()) << kShadowScale;
  59 }
  60 inline uptr MemToShadowSize(uptr size) {
  61   return size >> kShadowScale;
  62 }
  63
  64 bool MemIsApp(uptr p);
  65
  66 inline bool MemIsShadow(uptr p) {
  67   return (kLowShadowStart <= p && p <= kLowShadowEnd) ||
  68          (kHighShadowStart <= p && p <= kHighShadowEnd);
  69 }
  70
  71 uptr GetAliasRegionStart();
  72
  73 }  // namespace __hwasan
  74
  75 #endif  // HWASAN_MAPPING_H