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1//===-- asan_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-exception6//7//===----------------------------------------------------------------------===//8//9// This file is a part of AddressSanitizer, an address sanity checker.10//11// Defines ASan memory mapping.12//===----------------------------------------------------------------------===//13#ifndef ASAN_MAPPING_H14#define ASAN_MAPPING_H15 16#include "sanitizer_common/sanitizer_platform.h"17 18// The full explanation of the memory mapping could be found here:19// https://github.com/google/sanitizers/wiki/AddressSanitizerAlgorithm20//21// Typical shadow mapping on Linux/x86_64 with SHADOW_OFFSET == 0x00007fff8000:22// || `[0x10007fff8000, 0x7fffffffffff]` || HighMem ||23// || `[0x02008fff7000, 0x10007fff7fff]` || HighShadow ||24// || `[0x00008fff7000, 0x02008fff6fff]` || ShadowGap ||25// || `[0x00007fff8000, 0x00008fff6fff]` || LowShadow ||26// || `[0x000000000000, 0x00007fff7fff]` || LowMem ||27//28// When SHADOW_OFFSET is zero (-pie):29// || `[0x100000000000, 0x7fffffffffff]` || HighMem ||30// || `[0x020000000000, 0x0fffffffffff]` || HighShadow ||31// || `[0x000000040000, 0x01ffffffffff]` || ShadowGap ||32//33// Special case when something is already mapped between34// 0x003000000000 and 0x005000000000 (e.g. when prelink is installed):35// || `[0x10007fff8000, 0x7fffffffffff]` || HighMem ||36// || `[0x02008fff7000, 0x10007fff7fff]` || HighShadow ||37// || `[0x005000000000, 0x02008fff6fff]` || ShadowGap3 ||38// || `[0x003000000000, 0x004fffffffff]` || MidMem ||39// || `[0x000a7fff8000, 0x002fffffffff]` || ShadowGap2 ||40// || `[0x00067fff8000, 0x000a7fff7fff]` || MidShadow ||41// || `[0x00008fff7000, 0x00067fff7fff]` || ShadowGap ||42// || `[0x00007fff8000, 0x00008fff6fff]` || LowShadow ||43// || `[0x000000000000, 0x00007fff7fff]` || LowMem ||44//45// Default Linux/i386 mapping on x86_64 machine:46// || `[0x40000000, 0xffffffff]` || HighMem ||47// || `[0x28000000, 0x3fffffff]` || HighShadow ||48// || `[0x24000000, 0x27ffffff]` || ShadowGap ||49// || `[0x20000000, 0x23ffffff]` || LowShadow ||50// || `[0x00000000, 0x1fffffff]` || LowMem ||51//52// Default Linux/i386 mapping on i386 machine53// (addresses starting with 0xc0000000 are reserved54// for kernel and thus not sanitized):55// || `[0x38000000, 0xbfffffff]` || HighMem ||56// || `[0x27000000, 0x37ffffff]` || HighShadow ||57// || `[0x24000000, 0x26ffffff]` || ShadowGap ||58// || `[0x20000000, 0x23ffffff]` || LowShadow ||59// || `[0x00000000, 0x1fffffff]` || LowMem ||60//61// Default Linux/MIPS32 mapping:62// || `[0x2aaa0000, 0xffffffff]` || HighMem ||63// || `[0x0fff4000, 0x2aa9ffff]` || HighShadow ||64// || `[0x0bff4000, 0x0fff3fff]` || ShadowGap ||65// || `[0x0aaa0000, 0x0bff3fff]` || LowShadow ||66// || `[0x00000000, 0x0aa9ffff]` || LowMem ||67//68// Default Linux/MIPS64 mapping:69// || `[0x4000000000, 0xffffffffff]` || HighMem ||70// || `[0x2800000000, 0x3fffffffff]` || HighShadow ||71// || `[0x2400000000, 0x27ffffffff]` || ShadowGap ||72// || `[0x2000000000, 0x23ffffffff]` || LowShadow ||73// || `[0x0000000000, 0x1fffffffff]` || LowMem ||74//75// Default Linux/RISCV64 Sv39 mapping with SHADOW_OFFSET == 0xd55550000;76// (the exact location of SHADOW_OFFSET may vary depending the dynamic probing77// by FindDynamicShadowStart).78//79// || `[0x1555550000, 0x3fffffffff]` || HighMem ||80// || `[0x0fffffa000, 0x1555555fff]` || HighShadow ||81// || `[0x0effffa000, 0x0fffff9fff]` || ShadowGap ||82// || `[0x0d55550000, 0x0effff9fff]` || LowShadow ||83// || `[0x0000000000, 0x0d5554ffff]` || LowMem ||84//85// Default Linux/AArch64 (39-bit VMA) mapping:86// TODO: this mapping is ok, but the allocator size is too large on non-Android87// AArch64 platforms (see asan_allocator.h)88// || `[0x2000000000, 0x7fffffffff]` || highmem || 384GB89// || `[0x1400000000, 0x1fffffffff]` || highshadow || 48GB90// || `[0x1200000000, 0x13ffffffff]` || shadowgap || 8GB91// || `[0x1000000000, 0x11ffffffff]` || lowshadow || 8GB92// || `[0x0000000000, 0x0fffffffff]` || lowmem || 64GB93//94// Default Linux/AArch64 (42-bit VMA) mapping:95// TODO: this mapping is ok, but the allocator size is too large on non-Android96// AArch64 platforms (see asan_allocator.h)97// || `[0x09000000000, 0x03ffffffffff]` || highmem || 3520GB98// || `[0x02200000000, 0x008fffffffff]` || highshadow || 440GB99// || `[0x01200000000, 0x0021ffffffff]` || shadowgap || 64GB100// || `[0x01000000000, 0x0011ffffffff]` || lowshadow || 8GB101// || `[0x00000000000, 0x000fffffffff]` || lowmem || 64GB102//103// Default Linux/AArch64 (48-bit VMA) mapping:104// || `[0x201000000000, 0xffffffffffff]` || HighMem || 229312GB105// || `[0x041200000000, 0x200fffffffff]` || HighShadow || 28664GB106// || `[0x001200000000, 0x0411ffffffff]` || ShadowGap || 4096GB107// || `[0x001000000000, 0x0011ffffffff]` || LowShadow || 8GB108// || `[0x000000000000, 0x000fffffffff]` || LowMem || 64GB109//110// Default Linux/S390 mapping:111// || `[0x30000000, 0x7fffffff]` || HighMem ||112// || `[0x26000000, 0x2fffffff]` || HighShadow ||113// || `[0x24000000, 0x25ffffff]` || ShadowGap ||114// || `[0x20000000, 0x23ffffff]` || LowShadow ||115// || `[0x00000000, 0x1fffffff]` || LowMem ||116//117// Default Linux/SystemZ mapping:118// || `[0x14000000000000, 0x1fffffffffffff]` || HighMem ||119// || `[0x12800000000000, 0x13ffffffffffff]` || HighShadow ||120// || `[0x12000000000000, 0x127fffffffffff]` || ShadowGap ||121// || `[0x10000000000000, 0x11ffffffffffff]` || LowShadow ||122// || `[0x00000000000000, 0x0fffffffffffff]` || LowMem ||123//124// Default Linux/SPARC64 (52-bit VMA) mapping:125// || `[0x8000000000000, 0xfffffffffffff]` || HighMem ||126// || `[0x1080000000000, 0x207ffffffffff]` || HighShadow ||127// || `[0x0090000000000, 0x107ffffffffff]` || ShadowGap ||128// || `[0x0080000000000, 0x008ffffffffff]` || LowShadow ||129// || `[0x0000000000000, 0x007ffffffffff]` || LowMem ||130//131// Default Linux/LoongArch64 (47-bit VMA) mapping:132// || `[0x500000000000, 0x7fffffffffff]` || HighMem ||133// || `[0x4a0000000000, 0x4fffffffffff]` || HighShadow ||134// || `[0x480000000000, 0x49ffffffffff]` || ShadowGap ||135// || `[0x400000000000, 0x47ffffffffff]` || LowShadow ||136// || `[0x000000000000, 0x3fffffffffff]` || LowMem ||137//138// Shadow mapping on FreeBSD/x86-64 with SHADOW_OFFSET == 0x400000000000:139// || `[0x500000000000, 0x7fffffffffff]` || HighMem ||140// || `[0x4a0000000000, 0x4fffffffffff]` || HighShadow ||141// || `[0x480000000000, 0x49ffffffffff]` || ShadowGap ||142// || `[0x400000000000, 0x47ffffffffff]` || LowShadow ||143// || `[0x000000000000, 0x3fffffffffff]` || LowMem ||144//145// Shadow mapping on FreeBSD/i386 with SHADOW_OFFSET == 0x40000000:146// || `[0x60000000, 0xffffffff]` || HighMem ||147// || `[0x4c000000, 0x5fffffff]` || HighShadow ||148// || `[0x48000000, 0x4bffffff]` || ShadowGap ||149// || `[0x40000000, 0x47ffffff]` || LowShadow ||150// || `[0x00000000, 0x3fffffff]` || LowMem ||151//152// Shadow mapping on NetBSD/x86-64 with SHADOW_OFFSET == 0x400000000000:153// || `[0x4feffffffe01, 0x7f7ffffff000]` || HighMem ||154// || `[0x49fdffffffc0, 0x4feffffffe00]` || HighShadow ||155// || `[0x480000000000, 0x49fdffffffbf]` || ShadowGap ||156// || `[0x400000000000, 0x47ffffffffff]` || LowShadow ||157// || `[0x000000000000, 0x3fffffffffff]` || LowMem ||158//159// Shadow mapping on NetBSD/i386 with SHADOW_OFFSET == 0x40000000:160// || `[0x60000000, 0xfffff000]` || HighMem ||161// || `[0x4c000000, 0x5fffffff]` || HighShadow ||162// || `[0x48000000, 0x4bffffff]` || ShadowGap ||163// || `[0x40000000, 0x47ffffff]` || LowShadow ||164// || `[0x00000000, 0x3fffffff]` || LowMem ||165//166// Default Windows/i386 mapping:167// (the exact location of HighShadow/HighMem may vary depending168// on WoW64, /LARGEADDRESSAWARE, etc).169// || `[0x50000000, 0xffffffff]` || HighMem ||170// || `[0x3a000000, 0x4fffffff]` || HighShadow ||171// || `[0x36000000, 0x39ffffff]` || ShadowGap ||172// || `[0x30000000, 0x35ffffff]` || LowShadow ||173// || `[0x00000000, 0x2fffffff]` || LowMem ||174 175#define ASAN_SHADOW_SCALE 3176 177#if SANITIZER_FUCHSIA178# define ASAN_SHADOW_OFFSET_CONST (0)179#elif SANITIZER_WORDSIZE == 32180# if SANITIZER_ANDROID181# define ASAN_SHADOW_OFFSET_DYNAMIC182# elif defined(__mips__)183# define ASAN_SHADOW_OFFSET_CONST 0x0aaa0000184# elif SANITIZER_FREEBSD185# define ASAN_SHADOW_OFFSET_CONST 0x40000000186# elif SANITIZER_NETBSD187# define ASAN_SHADOW_OFFSET_CONST 0x40000000188# elif SANITIZER_WINDOWS189# define ASAN_SHADOW_OFFSET_CONST 0x30000000190# elif SANITIZER_IOS191# define ASAN_SHADOW_OFFSET_DYNAMIC192# else193# define ASAN_SHADOW_OFFSET_CONST 0x20000000194# endif195#else196# if SANITIZER_IOS197# define ASAN_SHADOW_OFFSET_DYNAMIC198# elif SANITIZER_APPLE && defined(__aarch64__)199# define ASAN_SHADOW_OFFSET_DYNAMIC200# elif SANITIZER_FREEBSD && defined(__aarch64__)201# define ASAN_SHADOW_OFFSET_CONST 0x0000800000000000202# elif SANITIZER_RISCV64203# define ASAN_SHADOW_OFFSET_DYNAMIC204# elif defined(__aarch64__)205# define ASAN_SHADOW_OFFSET_CONST 0x0000001000000000206# elif defined(__powerpc64__)207# define ASAN_SHADOW_OFFSET_CONST 0x0000100000000000208# elif defined(__s390x__)209# define ASAN_SHADOW_OFFSET_CONST 0x0010000000000000210# elif SANITIZER_FREEBSD211# define ASAN_SHADOW_OFFSET_CONST 0x0000400000000000212# elif SANITIZER_NETBSD213# define ASAN_SHADOW_OFFSET_CONST 0x0000400000000000214# elif SANITIZER_APPLE215# define ASAN_SHADOW_OFFSET_CONST 0x0000100000000000216# elif defined(__mips64)217# define ASAN_SHADOW_OFFSET_CONST 0x0000002000000000218# elif defined(__sparc__)219# define ASAN_SHADOW_OFFSET_CONST 0x0000080000000000220# elif SANITIZER_LOONGARCH64221# define ASAN_SHADOW_OFFSET_CONST 0x0000400000000000222# elif SANITIZER_WINDOWS64223# define ASAN_SHADOW_OFFSET_DYNAMIC224# else225# if ASAN_SHADOW_SCALE != 3226# error "Value below is based on shadow scale = 3."227# error "Original formula was: 0x7FFFFFFF & (~0xFFFULL << SHADOW_SCALE)."228# endif229# define ASAN_SHADOW_OFFSET_CONST 0x000000007fff8000230# endif231#endif232 233#if defined(__cplusplus)234# include "asan_internal.h"235 236static const u64 kDefaultShadowSentinel = ~(uptr)0;237 238# if defined(ASAN_SHADOW_OFFSET_CONST)239static const u64 kConstShadowOffset = ASAN_SHADOW_OFFSET_CONST;240# define ASAN_SHADOW_OFFSET kConstShadowOffset241# elif defined(ASAN_SHADOW_OFFSET_DYNAMIC)242# define ASAN_SHADOW_OFFSET __asan_shadow_memory_dynamic_address243# else244# error "ASAN_SHADOW_OFFSET can't be determined."245# endif246 247# if SANITIZER_ANDROID && defined(__arm__)248# define ASAN_PREMAP_SHADOW 1249# else250# define ASAN_PREMAP_SHADOW 0251# endif252 253# define ASAN_SHADOW_GRANULARITY (1ULL << ASAN_SHADOW_SCALE)254 255# define DO_ASAN_MAPPING_PROFILE 0 // Set to 1 to profile the functions below.256 257# if DO_ASAN_MAPPING_PROFILE258# define PROFILE_ASAN_MAPPING() AsanMappingProfile[__LINE__]++;259# else260# define PROFILE_ASAN_MAPPING()261# endif262 263// If 1, all shadow boundaries are constants.264// Don't set to 1 other than for testing.265# define ASAN_FIXED_MAPPING 0266 267namespace __asan {268 269extern uptr AsanMappingProfile[];270 271# if ASAN_FIXED_MAPPING272// Fixed mapping for 64-bit Linux. Mostly used for performance comparison273// with non-fixed mapping. As of r175253 (Feb 2013) the performance274// difference between fixed and non-fixed mapping is below the noise level.275static uptr kHighMemEnd = 0x7fffffffffffULL;276static uptr kMidMemBeg = 0x3000000000ULL;277static uptr kMidMemEnd = 0x4fffffffffULL;278# else279extern uptr kHighMemEnd, kMidMemBeg, kMidMemEnd; // Initialized in __asan_init.280# endif281 282} // namespace __asan283 284# if defined(__sparc__) && SANITIZER_WORDSIZE == 64285# include "asan_mapping_sparc64.h"286# else287# define MEM_TO_SHADOW(mem) \288 ((STRIP_MTE_TAG(mem) >> ASAN_SHADOW_SCALE) + (ASAN_SHADOW_OFFSET))289# define SHADOW_TO_MEM(mem) \290 (((mem) - (ASAN_SHADOW_OFFSET)) << (ASAN_SHADOW_SCALE))291 292# define kLowMemBeg 0293# define kLowMemEnd (ASAN_SHADOW_OFFSET ? ASAN_SHADOW_OFFSET - 1 : 0)294 295# define kLowShadowBeg ASAN_SHADOW_OFFSET296# define kLowShadowEnd MEM_TO_SHADOW(kLowMemEnd)297 298# define kHighMemBeg (MEM_TO_SHADOW(kHighMemEnd) + 1)299 300# define kHighShadowBeg MEM_TO_SHADOW(kHighMemBeg)301# define kHighShadowEnd MEM_TO_SHADOW(kHighMemEnd)302 303# define kMidShadowBeg MEM_TO_SHADOW(kMidMemBeg)304# define kMidShadowEnd MEM_TO_SHADOW(kMidMemEnd)305 306// With the zero shadow base we can not actually map pages starting from 0.307// This constant is somewhat arbitrary.308# define kZeroBaseShadowStart 0309# define kZeroBaseMaxShadowStart (1 << 18)310 311# define kShadowGapBeg \312 (kLowShadowEnd ? kLowShadowEnd + 1 : kZeroBaseShadowStart)313# define kShadowGapEnd ((kMidMemBeg ? kMidShadowBeg : kHighShadowBeg) - 1)314 315# define kShadowGap2Beg (kMidMemBeg ? kMidShadowEnd + 1 : 0)316# define kShadowGap2End (kMidMemBeg ? kMidMemBeg - 1 : 0)317 318# define kShadowGap3Beg (kMidMemBeg ? kMidMemEnd + 1 : 0)319# define kShadowGap3End (kMidMemBeg ? kHighShadowBeg - 1 : 0)320 321namespace __asan {322 323static inline bool AddrIsInLowMem(uptr a) {324 PROFILE_ASAN_MAPPING();325 return a <= kLowMemEnd;326}327 328static inline bool AddrIsInLowShadow(uptr a) {329 PROFILE_ASAN_MAPPING();330 return a >= kLowShadowBeg && a <= kLowShadowEnd;331}332 333static inline bool AddrIsInMidMem(uptr a) {334 PROFILE_ASAN_MAPPING();335 return kMidMemBeg && a >= kMidMemBeg && a <= kMidMemEnd;336}337 338static inline bool AddrIsInMidShadow(uptr a) {339 PROFILE_ASAN_MAPPING();340 return kMidMemBeg && a >= kMidShadowBeg && a <= kMidShadowEnd;341}342 343static inline bool AddrIsInHighMem(uptr a) {344 PROFILE_ASAN_MAPPING();345 return kHighMemBeg && a >= kHighMemBeg && a <= kHighMemEnd;346}347 348static inline bool AddrIsInHighShadow(uptr a) {349 PROFILE_ASAN_MAPPING();350 return kHighMemBeg && a >= kHighShadowBeg && a <= kHighShadowEnd;351}352 353static inline bool AddrIsInShadowGap(uptr a) {354 PROFILE_ASAN_MAPPING();355 if (kMidMemBeg) {356 if (a <= kShadowGapEnd)357 return ASAN_SHADOW_OFFSET == 0 || a >= kShadowGapBeg;358 return (a >= kShadowGap2Beg && a <= kShadowGap2End) ||359 (a >= kShadowGap3Beg && a <= kShadowGap3End);360 }361 // In zero-based shadow mode we treat addresses near zero as addresses362 // in shadow gap as well.363 if (ASAN_SHADOW_OFFSET == 0)364 return a <= kShadowGapEnd;365 return a >= kShadowGapBeg && a <= kShadowGapEnd;366}367 368} // namespace __asan369 370# endif371 372namespace __asan {373 374static inline uptr MemToShadowSize(uptr size) {375 return size >> ASAN_SHADOW_SCALE;376}377 378static inline bool AddrIsInMem(uptr a) {379 PROFILE_ASAN_MAPPING();380 a = STRIP_MTE_TAG(a);381 return AddrIsInLowMem(a) || AddrIsInMidMem(a) || AddrIsInHighMem(a) ||382 (flags()->protect_shadow_gap == 0 && AddrIsInShadowGap(a));383}384 385static inline uptr MemToShadow(uptr p) {386 PROFILE_ASAN_MAPPING();387 CHECK(AddrIsInMem(p));388 return MEM_TO_SHADOW(p);389}390 391static inline bool AddrIsInShadow(uptr a) {392 PROFILE_ASAN_MAPPING();393 a = STRIP_MTE_TAG(a);394 return AddrIsInLowShadow(a) || AddrIsInMidShadow(a) || AddrIsInHighShadow(a);395}396 397static inline uptr ShadowToMem(uptr p) {398 PROFILE_ASAN_MAPPING();399 CHECK(AddrIsInShadow(p));400 return SHADOW_TO_MEM(p);401}402 403static inline bool AddrIsAlignedByGranularity(uptr a) {404 PROFILE_ASAN_MAPPING();405 return (a & (ASAN_SHADOW_GRANULARITY - 1)) == 0;406}407 408static inline bool AddressIsPoisoned(uptr a) {409 PROFILE_ASAN_MAPPING();410 const uptr kAccessSize = 1;411 u8 *shadow_address = (u8 *)MEM_TO_SHADOW(a);412 s8 shadow_value = *shadow_address;413 if (shadow_value) {414 u8 last_accessed_byte =415 (a & (ASAN_SHADOW_GRANULARITY - 1)) + kAccessSize - 1;416 return (last_accessed_byte >= shadow_value);417 }418 return false;419}420 421// Must be after all calls to PROFILE_ASAN_MAPPING().422static const uptr kAsanMappingProfileSize = __LINE__;423 424} // namespace __asan425 426#endif // __cplusplus427 428#endif // ASAN_MAPPING_H429