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//===-- dfsan_platform.h ----------------------------------------*- C++ -*-===//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
// This file is a part of DataFlowSanitizer.
// Platform specific information for DFSan.
#include "sanitizer_common/sanitizer_common.h"
#include "sanitizer_common/sanitizer_platform.h"
namespace __dfsan {
using __sanitizer::uptr;
// TODO: The memory mapping code to setup a 1:1 shadow is based on msan.
// Consider refactoring these into a shared implementation.
struct MappingDesc {
uptr start;
uptr end;
enum Type { INVALID, APP, SHADOW, ORIGIN } type;
const char *name;
// All of the following configurations are supported.
// ASLR disabled: main executable and DSOs at 0x555550000000
// PIE and ASLR: main executable and DSOs at 0x7f0000000000
// non-PIE: main executable below 0x100000000, DSOs at 0x7f0000000000
// Heap at 0x700000000000.
const MappingDesc kMemoryLayout[] = {
{0x000000000000ULL, 0x010000000000ULL, MappingDesc::APP, "app-1"},
{0x010000000000ULL, 0x100000000000ULL, MappingDesc::SHADOW, "shadow-2"},
{0x100000000000ULL, 0x110000000000ULL, MappingDesc::INVALID, "invalid"},
{0x110000000000ULL, 0x200000000000ULL, MappingDesc::ORIGIN, "origin-2"},
{0x200000000000ULL, 0x300000000000ULL, MappingDesc::SHADOW, "shadow-3"},
{0x300000000000ULL, 0x400000000000ULL, MappingDesc::ORIGIN, "origin-3"},
{0x400000000000ULL, 0x500000000000ULL, MappingDesc::INVALID, "invalid"},
{0x500000000000ULL, 0x510000000000ULL, MappingDesc::SHADOW, "shadow-1"},
{0x510000000000ULL, 0x600000000000ULL, MappingDesc::APP, "app-2"},
{0x600000000000ULL, 0x610000000000ULL, MappingDesc::ORIGIN, "origin-1"},
{0x610000000000ULL, 0x700000000000ULL, MappingDesc::INVALID, "invalid"},
{0x700000000000ULL, 0x800000000000ULL, MappingDesc::APP, "app-3"}};
# define MEM_TO_SHADOW(mem) (((uptr)(mem)) ^ 0x500000000000ULL)
# define SHADOW_TO_ORIGIN(mem) (((uptr)(mem)) + 0x100000000000ULL)
# error "Unsupported platform"
const uptr kMemoryLayoutSize = sizeof(kMemoryLayout) / sizeof(kMemoryLayout[0]);
#ifndef __clang__
inline bool
addr_is_type(uptr addr, MappingDesc::Type mapping_type) {
// It is critical for performance that this loop is unrolled (because then it is
// simplified into just a few constant comparisons).
#ifdef __clang__
# pragma unroll
for (unsigned i = 0; i < kMemoryLayoutSize; ++i)
if (kMemoryLayout[i].type == mapping_type &&
addr >= kMemoryLayout[i].start && addr < kMemoryLayout[i].end)
return true;
return false;
#define MEM_IS_APP(mem) addr_is_type((uptr)(mem), MappingDesc::APP)
#define MEM_IS_SHADOW(mem) addr_is_type((uptr)(mem), MappingDesc::SHADOW)
#define MEM_IS_ORIGIN(mem) addr_is_type((uptr)(mem), MappingDesc::ORIGIN)
} // namespace __dfsan