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1//===-- dfsan_platform.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-exception6//7//===----------------------------------------------------------------------===//8//9// This file is a part of DataFlowSanitizer.10//11// Platform specific information for DFSan.12//===----------------------------------------------------------------------===//13 14#ifndef DFSAN_PLATFORM_H15#define DFSAN_PLATFORM_H16 17#include "sanitizer_common/sanitizer_common.h"18#include "sanitizer_common/sanitizer_platform.h"19 20namespace __dfsan {21 22using __sanitizer::uptr;23 24// TODO: The memory mapping code to setup a 1:1 shadow is based on msan.25// Consider refactoring these into a shared implementation.26 27struct MappingDesc {28 uptr start;29 uptr end;30 enum Type {31 INVALID = 1,32 ALLOCATOR = 2,33 APP = 4,34 SHADOW = 8,35 ORIGIN = 16,36 } type;37 const char *name;38};39 40// Note: MappingDesc::ALLOCATOR entries are only used to check for memory41// layout compatibility. The actual allocation settings are in42// dfsan_allocator.cpp, which need to be kept in sync.43#if SANITIZER_LINUX && SANITIZER_WORDSIZE == 6444 45# if defined(__aarch64__)46// The mapping assumes 48-bit VMA. AArch64 maps:47// - 0x0000000000000-0x0100000000000: 39/42/48-bits program own segments48// - 0x0a00000000000-0x0b00000000000: 48-bits PIE program segments49// Ideally, this would extend to 0x0c00000000000 (2^45 bytes - the50// maximum ASLR region for 48-bit VMA) but it is too hard to fit in51// the larger app/shadow/origin regions.52// - 0x0e00000000000-0x1000000000000: 48-bits libraries segments53const MappingDesc kMemoryLayout[] = {54 {0X0000000000000, 0X0100000000000, MappingDesc::APP, "app-10-13"},55 {0X0100000000000, 0X0200000000000, MappingDesc::SHADOW, "shadow-14"},56 {0X0200000000000, 0X0300000000000, MappingDesc::INVALID, "invalid"},57 {0X0300000000000, 0X0400000000000, MappingDesc::ORIGIN, "origin-14"},58 {0X0400000000000, 0X0600000000000, MappingDesc::SHADOW, "shadow-15"},59 {0X0600000000000, 0X0800000000000, MappingDesc::ORIGIN, "origin-15"},60 {0X0800000000000, 0X0A00000000000, MappingDesc::INVALID, "invalid"},61 {0X0A00000000000, 0X0B00000000000, MappingDesc::APP, "app-14"},62 {0X0B00000000000, 0X0C00000000000, MappingDesc::SHADOW, "shadow-10-13"},63 {0X0C00000000000, 0X0D00000000000, MappingDesc::INVALID, "invalid"},64 {0X0D00000000000, 0X0E00000000000, MappingDesc::ORIGIN, "origin-10-13"},65 {0X0E00000000000, 0X0E40000000000, MappingDesc::ALLOCATOR, "allocator"},66 {0X0E40000000000, 0X1000000000000, MappingDesc::APP, "app-15"},67};68# define MEM_TO_SHADOW(mem) ((uptr)mem ^ 0xB00000000000ULL)69# define SHADOW_TO_ORIGIN(shadow) (((uptr)(shadow)) + 0x200000000000ULL)70 71# else72// All of the following configurations are supported.73// ASLR disabled: main executable and DSOs at 0x55555000000074// PIE and ASLR: main executable and DSOs at 0x7f000000000075// non-PIE: main executable below 0x100000000, DSOs at 0x7f000000000076// Heap at 0x700000000000.77const MappingDesc kMemoryLayout[] = {78 {0x000000000000ULL, 0x010000000000ULL, MappingDesc::APP, "app-1"},79 {0x010000000000ULL, 0x100000000000ULL, MappingDesc::SHADOW, "shadow-2"},80 {0x100000000000ULL, 0x110000000000ULL, MappingDesc::INVALID, "invalid"},81 {0x110000000000ULL, 0x200000000000ULL, MappingDesc::ORIGIN, "origin-2"},82 {0x200000000000ULL, 0x300000000000ULL, MappingDesc::SHADOW, "shadow-3"},83 {0x300000000000ULL, 0x400000000000ULL, MappingDesc::ORIGIN, "origin-3"},84 {0x400000000000ULL, 0x500000000000ULL, MappingDesc::INVALID, "invalid"},85 {0x500000000000ULL, 0x510000000000ULL, MappingDesc::SHADOW, "shadow-1"},86 {0x510000000000ULL, 0x600000000000ULL, MappingDesc::APP, "app-2"},87 {0x600000000000ULL, 0x610000000000ULL, MappingDesc::ORIGIN, "origin-1"},88 {0x610000000000ULL, 0x700000000000ULL, MappingDesc::INVALID, "invalid"},89 {0x700000000000ULL, 0x740000000000ULL, MappingDesc::ALLOCATOR, "allocator"},90 {0x740000000000ULL, 0x800000000000ULL, MappingDesc::APP, "app-3"}};91# define MEM_TO_SHADOW(mem) (((uptr)(mem)) ^ 0x500000000000ULL)92# define SHADOW_TO_ORIGIN(mem) (((uptr)(mem)) + 0x100000000000ULL)93# endif94 95#else96# error "Unsupported platform"97#endif98 99const uptr kMemoryLayoutSize = sizeof(kMemoryLayout) / sizeof(kMemoryLayout[0]);100 101#define MEM_TO_ORIGIN(mem) (SHADOW_TO_ORIGIN(MEM_TO_SHADOW((mem))))102 103#ifndef __clang__104__attribute__((optimize("unroll-loops")))105#endif106inline bool107addr_is_type(uptr addr, int mapping_types) {108// It is critical for performance that this loop is unrolled (because then it is109// simplified into just a few constant comparisons).110#ifdef __clang__111# pragma unroll112#endif113 for (unsigned i = 0; i < kMemoryLayoutSize; ++i)114 if ((kMemoryLayout[i].type & mapping_types) &&115 addr >= kMemoryLayout[i].start && addr < kMemoryLayout[i].end)116 return true;117 return false;118}119 120#define MEM_IS_APP(mem) \121 (addr_is_type((uptr)(mem), MappingDesc::APP | MappingDesc::ALLOCATOR))122#define MEM_IS_SHADOW(mem) addr_is_type((uptr)(mem), MappingDesc::SHADOW)123#define MEM_IS_ORIGIN(mem) addr_is_type((uptr)(mem), MappingDesc::ORIGIN)124 125} // namespace __dfsan126 127#endif128