asan_mapping.h revision 1.8
1//===-- asan_mapping.h ------------------------------------------*- C++ -*-===// 2// 3// This file is distributed under the University of Illinois Open Source 4// License. See LICENSE.TXT for details. 5// 6//===----------------------------------------------------------------------===// 7// 8// This file is a part of AddressSanitizer, an address sanity checker. 9// 10// Defines ASan memory mapping. 11//===----------------------------------------------------------------------===// 12#ifndef ASAN_MAPPING_H 13#define ASAN_MAPPING_H 14 15#include "asan_internal.h" 16 17// The full explanation of the memory mapping could be found here: 18// https://github.com/google/sanitizers/wiki/AddressSanitizerAlgorithm 19// 20// Typical shadow mapping on Linux/x86_64 with SHADOW_OFFSET == 0x00007fff8000: 21// || `[0x10007fff8000, 0x7fffffffffff]` || HighMem || 22// || `[0x02008fff7000, 0x10007fff7fff]` || HighShadow || 23// || `[0x00008fff7000, 0x02008fff6fff]` || ShadowGap || 24// || `[0x00007fff8000, 0x00008fff6fff]` || LowShadow || 25// || `[0x000000000000, 0x00007fff7fff]` || LowMem || 26// 27// When SHADOW_OFFSET is zero (-pie): 28// || `[0x100000000000, 0x7fffffffffff]` || HighMem || 29// || `[0x020000000000, 0x0fffffffffff]` || HighShadow || 30// || `[0x000000040000, 0x01ffffffffff]` || ShadowGap || 31// 32// Special case when something is already mapped between 33// 0x003000000000 and 0x005000000000 (e.g. when prelink is installed): 34// || `[0x10007fff8000, 0x7fffffffffff]` || HighMem || 35// || `[0x02008fff7000, 0x10007fff7fff]` || HighShadow || 36// || `[0x005000000000, 0x02008fff6fff]` || ShadowGap3 || 37// || `[0x003000000000, 0x004fffffffff]` || MidMem || 38// || `[0x000a7fff8000, 0x002fffffffff]` || ShadowGap2 || 39// || `[0x00067fff8000, 0x000a7fff7fff]` || MidShadow || 40// || `[0x00008fff7000, 0x00067fff7fff]` || ShadowGap || 41// || `[0x00007fff8000, 0x00008fff6fff]` || LowShadow || 42// || `[0x000000000000, 0x00007fff7fff]` || LowMem || 43// 44// Default Linux/i386 mapping on x86_64 machine: 45// || `[0x40000000, 0xffffffff]` || HighMem || 46// || `[0x28000000, 0x3fffffff]` || HighShadow || 47// || `[0x24000000, 0x27ffffff]` || ShadowGap || 48// || `[0x20000000, 0x23ffffff]` || LowShadow || 49// || `[0x00000000, 0x1fffffff]` || LowMem || 50// 51// Default Linux/i386 mapping on i386 machine 52// (addresses starting with 0xc0000000 are reserved 53// for kernel and thus not sanitized): 54// || `[0x38000000, 0xbfffffff]` || HighMem || 55// || `[0x27000000, 0x37ffffff]` || HighShadow || 56// || `[0x24000000, 0x26ffffff]` || ShadowGap || 57// || `[0x20000000, 0x23ffffff]` || LowShadow || 58// || `[0x00000000, 0x1fffffff]` || LowMem || 59// 60// Default Linux/MIPS32 mapping: 61// || `[0x2aaa0000, 0xffffffff]` || HighMem || 62// || `[0x0fff4000, 0x2aa9ffff]` || HighShadow || 63// || `[0x0bff4000, 0x0fff3fff]` || ShadowGap || 64// || `[0x0aaa0000, 0x0bff3fff]` || LowShadow || 65// || `[0x00000000, 0x0aa9ffff]` || LowMem || 66// 67// Default Linux/MIPS64 mapping: 68// || `[0x4000000000, 0xffffffffff]` || HighMem || 69// || `[0x2800000000, 0x3fffffffff]` || HighShadow || 70// || `[0x2400000000, 0x27ffffffff]` || ShadowGap || 71// || `[0x2000000000, 0x23ffffffff]` || LowShadow || 72// || `[0x0000000000, 0x1fffffffff]` || LowMem || 73// 74// Default Linux/AArch64 (39-bit VMA) mapping: 75// || `[0x2000000000, 0x7fffffffff]` || highmem || 76// || `[0x1400000000, 0x1fffffffff]` || highshadow || 77// || `[0x1200000000, 0x13ffffffff]` || shadowgap || 78// || `[0x1000000000, 0x11ffffffff]` || lowshadow || 79// || `[0x0000000000, 0x0fffffffff]` || lowmem || 80// 81// Default Linux/AArch64 (42-bit VMA) mapping: 82// || `[0x10000000000, 0x3ffffffffff]` || highmem || 83// || `[0x0a000000000, 0x0ffffffffff]` || highshadow || 84// || `[0x09000000000, 0x09fffffffff]` || shadowgap || 85// || `[0x08000000000, 0x08fffffffff]` || lowshadow || 86// || `[0x00000000000, 0x07fffffffff]` || lowmem || 87// 88// Default Linux/S390 mapping: 89// || `[0x30000000, 0x7fffffff]` || HighMem || 90// || `[0x26000000, 0x2fffffff]` || HighShadow || 91// || `[0x24000000, 0x25ffffff]` || ShadowGap || 92// || `[0x20000000, 0x23ffffff]` || LowShadow || 93// || `[0x00000000, 0x1fffffff]` || LowMem || 94// 95// Default Linux/SystemZ mapping: 96// || `[0x14000000000000, 0x1fffffffffffff]` || HighMem || 97// || `[0x12800000000000, 0x13ffffffffffff]` || HighShadow || 98// || `[0x12000000000000, 0x127fffffffffff]` || ShadowGap || 99// || `[0x10000000000000, 0x11ffffffffffff]` || LowShadow || 100// || `[0x00000000000000, 0x0fffffffffffff]` || LowMem || 101// 102// Default Linux/SPARC64 (52-bit VMA) mapping: 103// || `[0x8000000000000, 0xfffffffffffff]` || HighMem || 104// || `[0x1080000000000, 0x207ffffffffff]` || HighShadow || 105// || `[0x0090000000000, 0x107ffffffffff]` || ShadowGap || 106// || `[0x0080000000000, 0x008ffffffffff]` || LowShadow || 107// || `[0x0000000000000, 0x007ffffffffff]` || LowMem || 108// 109// Shadow mapping on FreeBSD/x86-64 with SHADOW_OFFSET == 0x400000000000: 110// || `[0x500000000000, 0x7fffffffffff]` || HighMem || 111// || `[0x4a0000000000, 0x4fffffffffff]` || HighShadow || 112// || `[0x480000000000, 0x49ffffffffff]` || ShadowGap || 113// || `[0x400000000000, 0x47ffffffffff]` || LowShadow || 114// || `[0x000000000000, 0x3fffffffffff]` || LowMem || 115// 116// Shadow mapping on FreeBSD/i386 with SHADOW_OFFSET == 0x40000000: 117// || `[0x60000000, 0xffffffff]` || HighMem || 118// || `[0x4c000000, 0x5fffffff]` || HighShadow || 119// || `[0x48000000, 0x4bffffff]` || ShadowGap || 120// || `[0x40000000, 0x47ffffff]` || LowShadow || 121// || `[0x00000000, 0x3fffffff]` || LowMem || 122// 123// Shadow mapping on NetBSD/x86-64 with SHADOW_OFFSET == 0x400000000000: 124// || `[0x4feffffffe01, 0x7f7ffffff000]` || HighMem || 125// || `[0x49fdffffffc0, 0x4feffffffe00]` || HighShadow || 126// || `[0x480000000000, 0x49fdffffffbf]` || ShadowGap || 127// || `[0x400000000000, 0x47ffffffffff]` || LowShadow || 128// || `[0x000000000000, 0x3fffffffffff]` || LowMem || 129// 130// Shadow mapping on NetBSD/i386 with SHADOW_OFFSET == 0x40000000: 131// || `[0x60000000, 0xfffff000]` || HighMem || 132// || `[0x4c000000, 0x5fffffff]` || HighShadow || 133// || `[0x48000000, 0x4bffffff]` || ShadowGap || 134// || `[0x40000000, 0x47ffffff]` || LowShadow || 135// || `[0x00000000, 0x3fffffff]` || LowMem || 136// 137// Default Windows/i386 mapping: 138// (the exact location of HighShadow/HighMem may vary depending 139// on WoW64, /LARGEADDRESSAWARE, etc). 140// || `[0x50000000, 0xffffffff]` || HighMem || 141// || `[0x3a000000, 0x4fffffff]` || HighShadow || 142// || `[0x36000000, 0x39ffffff]` || ShadowGap || 143// || `[0x30000000, 0x35ffffff]` || LowShadow || 144// || `[0x00000000, 0x2fffffff]` || LowMem || 145// 146// Shadow mapping on Myriad2 (for shadow scale 5): 147// || `[0x9ff80000, 0x9fffffff]` || ShadowGap || 148// || `[0x9f000000, 0x9ff7ffff]` || LowShadow || 149// || `[0x80000000, 0x9effffff]` || LowMem || 150// || `[0x00000000, 0x7fffffff]` || Ignored || 151 152#if defined(ASAN_SHADOW_SCALE) 153static const u64 kDefaultShadowScale = ASAN_SHADOW_SCALE; 154#else 155static const u64 kDefaultShadowScale = SANITIZER_MYRIAD2 ? 5 : 3; 156#endif 157static const u64 kDefaultShadowSentinel = ~(uptr)0; 158static const u64 kDefaultShadowOffset32 = 1ULL << 29; // 0x20000000 159static const u64 kDefaultShadowOffset64 = 1ULL << 44; 160static const u64 kDefaultShort64bitShadowOffset = 161 0x7FFFFFFF & (~0xFFFULL << kDefaultShadowScale); // < 2G. 162static const u64 kIosShadowOffset32 = 1ULL << 30; // 0x40000000 163static const u64 kIosShadowOffset64 = 0x120200000; 164static const u64 kIosSimShadowOffset32 = 1ULL << 30; 165static const u64 kIosSimShadowOffset64 = kDefaultShadowOffset64; 166static const u64 kAArch64_ShadowOffset64 = 1ULL << 36; 167static const u64 kMIPS32_ShadowOffset32 = 0x0aaa0000; 168static const u64 kMIPS64_ShadowOffset64 = 1ULL << 37; 169static const u64 kPPC64_ShadowOffset64 = 1ULL << 41; 170static const u64 kSystemZ_ShadowOffset64 = 1ULL << 52; 171static const u64 kSPARC64_ShadowOffset64 = 1ULL << 43; // 0x80000000000 172static const u64 kFreeBSD_ShadowOffset32 = 1ULL << 30; // 0x40000000 173static const u64 kFreeBSD_ShadowOffset64 = 1ULL << 46; // 0x400000000000 174static const u64 kNetBSD_ShadowOffset32 = 1ULL << 30; // 0x40000000 175static const u64 kNetBSD_ShadowOffset64 = 1ULL << 46; // 0x400000000000 176static const u64 kWindowsShadowOffset32 = 3ULL << 28; // 0x30000000 177 178static const u64 kMyriadMemoryOffset32 = 0x80000000ULL; 179static const u64 kMyriadMemorySize32 = 0x20000000ULL; 180static const u64 kMyriadMemoryEnd32 = 181 kMyriadMemoryOffset32 + kMyriadMemorySize32 - 1; 182static const u64 kMyriadShadowOffset32 = 183 (kMyriadMemoryOffset32 + kMyriadMemorySize32 - 184 (kMyriadMemorySize32 >> kDefaultShadowScale)); 185static const u64 kMyriadCacheBitMask32 = 0x40000000ULL; 186 187#define SHADOW_SCALE kDefaultShadowScale 188 189#if SANITIZER_FUCHSIA 190# define SHADOW_OFFSET (0) 191#elif SANITIZER_WORDSIZE == 32 192# if SANITIZER_ANDROID 193# define SHADOW_OFFSET __asan_shadow_memory_dynamic_address 194# elif defined(__mips__) 195# define SHADOW_OFFSET kMIPS32_ShadowOffset32 196# elif SANITIZER_FREEBSD 197# define SHADOW_OFFSET kFreeBSD_ShadowOffset32 198# elif SANITIZER_NETBSD 199# define SHADOW_OFFSET kNetBSD_ShadowOffset32 200# elif SANITIZER_WINDOWS 201# define SHADOW_OFFSET kWindowsShadowOffset32 202# elif SANITIZER_IOS 203# if SANITIZER_IOSSIM 204# define SHADOW_OFFSET kIosSimShadowOffset32 205# else 206# define SHADOW_OFFSET kIosShadowOffset32 207# endif 208# elif SANITIZER_MYRIAD2 209# define SHADOW_OFFSET kMyriadShadowOffset32 210# else 211# define SHADOW_OFFSET kDefaultShadowOffset32 212# endif 213#else 214# if SANITIZER_IOS 215# if SANITIZER_IOSSIM 216# define SHADOW_OFFSET kIosSimShadowOffset64 217# else 218# define SHADOW_OFFSET __asan_shadow_memory_dynamic_address 219# endif 220# elif defined(__aarch64__) 221# define SHADOW_OFFSET kAArch64_ShadowOffset64 222# elif defined(__powerpc64__) 223# define SHADOW_OFFSET kPPC64_ShadowOffset64 224# elif defined(__s390x__) 225# define SHADOW_OFFSET kSystemZ_ShadowOffset64 226# elif SANITIZER_FREEBSD 227# define SHADOW_OFFSET kFreeBSD_ShadowOffset64 228// XXX: see TARGET_ASAN_SHADOW_OFFSET in gcc. 229// for example ix86_asan_shadow_offset() in i386.c 230// # elif SANITIZER_NETBSD 231// # define SHADOW_OFFSET kNetBSD_ShadowOffset64 232# elif SANITIZER_MAC 233# define SHADOW_OFFSET kDefaultShadowOffset64 234# elif defined(__mips64) 235# define SHADOW_OFFSET kMIPS64_ShadowOffset64 236# elif defined(__sparc__) 237# define SHADOW_OFFSET kSPARC64_ShadowOffset64 238# elif SANITIZER_WINDOWS64 239# define SHADOW_OFFSET __asan_shadow_memory_dynamic_address 240# else 241# define SHADOW_OFFSET kDefaultShort64bitShadowOffset 242# endif 243#endif 244 245#if SANITIZER_ANDROID && defined(__arm__) 246# define ASAN_PREMAP_SHADOW 1 247#else 248# define ASAN_PREMAP_SHADOW 0 249#endif 250 251#define SHADOW_GRANULARITY (1ULL << SHADOW_SCALE) 252 253#define DO_ASAN_MAPPING_PROFILE 0 // Set to 1 to profile the functions below. 254 255#if DO_ASAN_MAPPING_PROFILE 256# define PROFILE_ASAN_MAPPING() AsanMappingProfile[__LINE__]++; 257#else 258# define PROFILE_ASAN_MAPPING() 259#endif 260 261// If 1, all shadow boundaries are constants. 262// Don't set to 1 other than for testing. 263#define ASAN_FIXED_MAPPING 0 264 265namespace __asan { 266 267extern uptr AsanMappingProfile[]; 268 269#if ASAN_FIXED_MAPPING 270// Fixed mapping for 64-bit Linux. Mostly used for performance comparison 271// with non-fixed mapping. As of r175253 (Feb 2013) the performance 272// difference between fixed and non-fixed mapping is below the noise level. 273static uptr kHighMemEnd = 0x7fffffffffffULL; 274static uptr kMidMemBeg = 0x3000000000ULL; 275static uptr kMidMemEnd = 0x4fffffffffULL; 276#else 277extern uptr kHighMemEnd, kMidMemBeg, kMidMemEnd; // Initialized in __asan_init. 278#endif 279 280} // namespace __asan 281 282#if SANITIZER_MYRIAD2 283#include "asan_mapping_myriad.h" 284#elif defined(__sparc__) && SANITIZER_WORDSIZE == 64 285#include "asan_mapping_sparc64.h" 286#else 287#define MEM_TO_SHADOW(mem) (((mem) >> SHADOW_SCALE) + (SHADOW_OFFSET)) 288 289#define kLowMemBeg 0 290#define kLowMemEnd (SHADOW_OFFSET ? SHADOW_OFFSET - 1 : 0) 291 292#define kLowShadowBeg SHADOW_OFFSET 293#define kLowShadowEnd MEM_TO_SHADOW(kLowMemEnd) 294 295#define kHighMemBeg (MEM_TO_SHADOW(kHighMemEnd) + 1) 296 297#define kHighShadowBeg MEM_TO_SHADOW(kHighMemBeg) 298#define kHighShadowEnd MEM_TO_SHADOW(kHighMemEnd) 299 300# define kMidShadowBeg MEM_TO_SHADOW(kMidMemBeg) 301# define kMidShadowEnd MEM_TO_SHADOW(kMidMemEnd) 302 303// With the zero shadow base we can not actually map pages starting from 0. 304// This constant is somewhat arbitrary. 305#define kZeroBaseShadowStart 0 306#define kZeroBaseMaxShadowStart (1 << 18) 307 308#define kShadowGapBeg (kLowShadowEnd ? kLowShadowEnd + 1 \ 309 : kZeroBaseShadowStart) 310#define kShadowGapEnd ((kMidMemBeg ? kMidShadowBeg : kHighShadowBeg) - 1) 311 312#define kShadowGap2Beg (kMidMemBeg ? kMidShadowEnd + 1 : 0) 313#define kShadowGap2End (kMidMemBeg ? kMidMemBeg - 1 : 0) 314 315#define kShadowGap3Beg (kMidMemBeg ? kMidMemEnd + 1 : 0) 316#define kShadowGap3End (kMidMemBeg ? kHighShadowBeg - 1 : 0) 317 318namespace __asan { 319 320static inline bool AddrIsInLowMem(uptr a) { 321 PROFILE_ASAN_MAPPING(); 322 return a <= kLowMemEnd; 323} 324 325static inline bool AddrIsInLowShadow(uptr a) { 326 PROFILE_ASAN_MAPPING(); 327 return a >= kLowShadowBeg && a <= kLowShadowEnd; 328} 329 330static inline bool AddrIsInMidMem(uptr a) { 331 PROFILE_ASAN_MAPPING(); 332 return kMidMemBeg && a >= kMidMemBeg && a <= kMidMemEnd; 333} 334 335static inline bool AddrIsInMidShadow(uptr a) { 336 PROFILE_ASAN_MAPPING(); 337 return kMidMemBeg && a >= kMidShadowBeg && a <= kMidShadowEnd; 338} 339 340static inline bool AddrIsInHighMem(uptr a) { 341 PROFILE_ASAN_MAPPING(); 342 return kHighMemBeg && a >= kHighMemBeg && a <= kHighMemEnd; 343} 344 345static inline bool AddrIsInHighShadow(uptr a) { 346 PROFILE_ASAN_MAPPING(); 347 return kHighMemBeg && a >= kHighShadowBeg && a <= kHighShadowEnd; 348} 349 350static inline bool AddrIsInShadowGap(uptr a) { 351 PROFILE_ASAN_MAPPING(); 352 if (kMidMemBeg) { 353 if (a <= kShadowGapEnd) 354 return SHADOW_OFFSET == 0 || a >= kShadowGapBeg; 355 return (a >= kShadowGap2Beg && a <= kShadowGap2End) || 356 (a >= kShadowGap3Beg && a <= kShadowGap3End); 357 } 358 // In zero-based shadow mode we treat addresses near zero as addresses 359 // in shadow gap as well. 360 if (SHADOW_OFFSET == 0) 361 return a <= kShadowGapEnd; 362 return a >= kShadowGapBeg && a <= kShadowGapEnd; 363} 364 365} // namespace __asan 366 367#endif // SANITIZER_MYRIAD2 368 369namespace __asan { 370 371static inline bool AddrIsInMem(uptr a) { 372 PROFILE_ASAN_MAPPING(); 373 return AddrIsInLowMem(a) || AddrIsInMidMem(a) || AddrIsInHighMem(a) || 374 (flags()->protect_shadow_gap == 0 && AddrIsInShadowGap(a)); 375} 376 377static inline uptr MemToShadow(uptr p) { 378 PROFILE_ASAN_MAPPING(); 379 CHECK(AddrIsInMem(p)); 380 return MEM_TO_SHADOW(p); 381} 382 383static inline bool AddrIsInShadow(uptr a) { 384 PROFILE_ASAN_MAPPING(); 385 return AddrIsInLowShadow(a) || AddrIsInMidShadow(a) || AddrIsInHighShadow(a); 386} 387 388static inline bool AddrIsAlignedByGranularity(uptr a) { 389 PROFILE_ASAN_MAPPING(); 390 return (a & (SHADOW_GRANULARITY - 1)) == 0; 391} 392 393static inline bool AddressIsPoisoned(uptr a) { 394 PROFILE_ASAN_MAPPING(); 395 if (SANITIZER_MYRIAD2 && !AddrIsInMem(a) && !AddrIsInShadow(a)) 396 return false; 397 const uptr kAccessSize = 1; 398 u8 *shadow_address = (u8*)MEM_TO_SHADOW(a); 399 s8 shadow_value = *shadow_address; 400 if (shadow_value) { 401 u8 last_accessed_byte = (a & (SHADOW_GRANULARITY - 1)) 402 + kAccessSize - 1; 403 return (last_accessed_byte >= shadow_value); 404 } 405 return false; 406} 407 408// Must be after all calls to PROFILE_ASAN_MAPPING(). 409static const uptr kAsanMappingProfileSize = __LINE__; 410 411} // namespace __asan 412 413#endif // ASAN_MAPPING_H 414