1 //===-- asan_mapping.h ------------------------------------------*- C++ -*-===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is distributed under the University of Illinois Open Source 6 // License. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 // 10 // This file is a part of AddressSanitizer, an address sanity checker. 11 // 12 // Defines ASan memory mapping. 13 //===----------------------------------------------------------------------===// 14 #ifndef ASAN_MAPPING_H 15 #define ASAN_MAPPING_H 16 17 #include "asan_internal.h" 18 19 // The full explanation of the memory mapping could be found here: 20 // https://github.com/google/sanitizers/wiki/AddressSanitizerAlgorithm 21 // 22 // Typical shadow mapping on Linux/x86_64 with SHADOW_OFFSET == 0x00007fff8000: 23 // || `[0x10007fff8000, 0x7fffffffffff]` || HighMem || 24 // || `[0x02008fff7000, 0x10007fff7fff]` || HighShadow || 25 // || `[0x00008fff7000, 0x02008fff6fff]` || ShadowGap || 26 // || `[0x00007fff8000, 0x00008fff6fff]` || LowShadow || 27 // || `[0x000000000000, 0x00007fff7fff]` || LowMem || 28 // 29 // When SHADOW_OFFSET is zero (-pie): 30 // || `[0x100000000000, 0x7fffffffffff]` || HighMem || 31 // || `[0x020000000000, 0x0fffffffffff]` || HighShadow || 32 // || `[0x000000040000, 0x01ffffffffff]` || ShadowGap || 33 // 34 // Special case when something is already mapped between 35 // 0x003000000000 and 0x005000000000 (e.g. when prelink is installed): 36 // || `[0x10007fff8000, 0x7fffffffffff]` || HighMem || 37 // || `[0x02008fff7000, 0x10007fff7fff]` || HighShadow || 38 // || `[0x005000000000, 0x02008fff6fff]` || ShadowGap3 || 39 // || `[0x003000000000, 0x004fffffffff]` || MidMem || 40 // || `[0x000a7fff8000, 0x002fffffffff]` || ShadowGap2 || 41 // || `[0x00067fff8000, 0x000a7fff7fff]` || MidShadow || 42 // || `[0x00008fff7000, 0x00067fff7fff]` || ShadowGap || 43 // || `[0x00007fff8000, 0x00008fff6fff]` || LowShadow || 44 // || `[0x000000000000, 0x00007fff7fff]` || LowMem || 45 // 46 // Default Linux/i386 mapping on x86_64 machine: 47 // || `[0x40000000, 0xffffffff]` || HighMem || 48 // || `[0x28000000, 0x3fffffff]` || HighShadow || 49 // || `[0x24000000, 0x27ffffff]` || ShadowGap || 50 // || `[0x20000000, 0x23ffffff]` || LowShadow || 51 // || `[0x00000000, 0x1fffffff]` || LowMem || 52 // 53 // Default Linux/i386 mapping on i386 machine 54 // (addresses starting with 0xc0000000 are reserved 55 // for kernel and thus not sanitized): 56 // || `[0x38000000, 0xbfffffff]` || HighMem || 57 // || `[0x27000000, 0x37ffffff]` || HighShadow || 58 // || `[0x24000000, 0x26ffffff]` || ShadowGap || 59 // || `[0x20000000, 0x23ffffff]` || LowShadow || 60 // || `[0x00000000, 0x1fffffff]` || LowMem || 61 // 62 // Default Linux/MIPS32 mapping: 63 // || `[0x2aaa0000, 0xffffffff]` || HighMem || 64 // || `[0x0fff4000, 0x2aa9ffff]` || HighShadow || 65 // || `[0x0bff4000, 0x0fff3fff]` || ShadowGap || 66 // || `[0x0aaa0000, 0x0bff3fff]` || LowShadow || 67 // || `[0x00000000, 0x0aa9ffff]` || LowMem || 68 // 69 // Default Linux/MIPS64 mapping: 70 // || `[0x4000000000, 0xffffffffff]` || HighMem || 71 // || `[0x2800000000, 0x3fffffffff]` || HighShadow || 72 // || `[0x2400000000, 0x27ffffffff]` || ShadowGap || 73 // || `[0x2000000000, 0x23ffffffff]` || LowShadow || 74 // || `[0x0000000000, 0x1fffffffff]` || LowMem || 75 // 76 // Default Linux/AArch64 (39-bit VMA) mapping: 77 // || `[0x2000000000, 0x7fffffffff]` || highmem || 78 // || `[0x1400000000, 0x1fffffffff]` || highshadow || 79 // || `[0x1200000000, 0x13ffffffff]` || shadowgap || 80 // || `[0x1000000000, 0x11ffffffff]` || lowshadow || 81 // || `[0x0000000000, 0x0fffffffff]` || lowmem || 82 // 83 // Default Linux/AArch64 (42-bit VMA) mapping: 84 // || `[0x10000000000, 0x3ffffffffff]` || highmem || 85 // || `[0x0a000000000, 0x0ffffffffff]` || highshadow || 86 // || `[0x09000000000, 0x09fffffffff]` || shadowgap || 87 // || `[0x08000000000, 0x08fffffffff]` || lowshadow || 88 // || `[0x00000000000, 0x07fffffffff]` || lowmem || 89 // 90 // Default Linux/S390 mapping: 91 // || `[0x30000000, 0x7fffffff]` || HighMem || 92 // || `[0x26000000, 0x2fffffff]` || HighShadow || 93 // || `[0x24000000, 0x25ffffff]` || ShadowGap || 94 // || `[0x20000000, 0x23ffffff]` || LowShadow || 95 // || `[0x00000000, 0x1fffffff]` || LowMem || 96 // 97 // Default Linux/SystemZ mapping: 98 // || `[0x14000000000000, 0x1fffffffffffff]` || HighMem || 99 // || `[0x12800000000000, 0x13ffffffffffff]` || HighShadow || 100 // || `[0x12000000000000, 0x127fffffffffff]` || ShadowGap || 101 // || `[0x10000000000000, 0x11ffffffffffff]` || LowShadow || 102 // || `[0x00000000000000, 0x0fffffffffffff]` || LowMem || 103 // 104 // Shadow mapping on FreeBSD/x86-64 with SHADOW_OFFSET == 0x400000000000: 105 // || `[0x500000000000, 0x7fffffffffff]` || HighMem || 106 // || `[0x4a0000000000, 0x4fffffffffff]` || HighShadow || 107 // || `[0x480000000000, 0x49ffffffffff]` || ShadowGap || 108 // || `[0x400000000000, 0x47ffffffffff]` || LowShadow || 109 // || `[0x000000000000, 0x3fffffffffff]` || LowMem || 110 // 111 // Shadow mapping on FreeBSD/i386 with SHADOW_OFFSET == 0x40000000: 112 // || `[0x60000000, 0xffffffff]` || HighMem || 113 // || `[0x4c000000, 0x5fffffff]` || HighShadow || 114 // || `[0x48000000, 0x4bffffff]` || ShadowGap || 115 // || `[0x40000000, 0x47ffffff]` || LowShadow || 116 // || `[0x00000000, 0x3fffffff]` || LowMem || 117 // 118 // Shadow mapping on NetBSD/x86-64 with SHADOW_OFFSET == 0x400000000000: 119 // || `[0x4feffffffe01, 0x7f7ffffff000]` || HighMem || 120 // || `[0x49fdffffffc0, 0x4feffffffe00]` || HighShadow || 121 // || `[0x480000000000, 0x49fdffffffbf]` || ShadowGap || 122 // || `[0x400000000000, 0x47ffffffffff]` || LowShadow || 123 // || `[0x000000000000, 0x3fffffffffff]` || LowMem || 124 // 125 // Shadow mapping on NetBSD/i386 with SHADOW_OFFSET == 0x40000000: 126 // || `[0x60000000, 0xfffff000]` || HighMem || 127 // || `[0x4c000000, 0x5fffffff]` || HighShadow || 128 // || `[0x48000000, 0x4bffffff]` || ShadowGap || 129 // || `[0x40000000, 0x47ffffff]` || LowShadow || 130 // || `[0x00000000, 0x3fffffff]` || LowMem || 131 // 132 // Default Windows/i386 mapping: 133 // (the exact location of HighShadow/HighMem may vary depending 134 // on WoW64, /LARGEADDRESSAWARE, etc). 135 // || `[0x50000000, 0xffffffff]` || HighMem || 136 // || `[0x3a000000, 0x4fffffff]` || HighShadow || 137 // || `[0x36000000, 0x39ffffff]` || ShadowGap || 138 // || `[0x30000000, 0x35ffffff]` || LowShadow || 139 // || `[0x00000000, 0x2fffffff]` || LowMem || 140 // 141 // Shadow mapping on Myriad2 (for shadow scale 5): 142 // || `[0x9ff80000, 0x9fffffff]` || ShadowGap || 143 // || `[0x9f000000, 0x9ff7ffff]` || LowShadow || 144 // || `[0x80000000, 0x9effffff]` || LowMem || 145 // || `[0x00000000, 0x7fffffff]` || Ignored || 146 147 #if defined(ASAN_SHADOW_SCALE) 148 static const u64 kDefaultShadowScale = ASAN_SHADOW_SCALE; 149 #else 150 static const u64 kDefaultShadowScale = SANITIZER_MYRIAD2 ? 5 : 3; 151 #endif 152 static const u64 kDefaultShadowSentinel = ~(uptr)0; 153 static const u64 kDefaultShadowOffset32 = 1ULL << 29; // 0x20000000 154 static const u64 kDefaultShadowOffset64 = 1ULL << 44; 155 static const u64 kDefaultShort64bitShadowOffset = 156 0x7FFFFFFF & (~0xFFFULL << kDefaultShadowScale); // < 2G. 157 static const u64 kIosShadowOffset32 = 1ULL << 30; // 0x40000000 158 static const u64 kIosShadowOffset64 = 0x120200000; 159 static const u64 kIosSimShadowOffset32 = 1ULL << 30; 160 static const u64 kIosSimShadowOffset64 = kDefaultShadowOffset64; 161 static const u64 kAArch64_ShadowOffset64 = 1ULL << 36; 162 static const u64 kMIPS32_ShadowOffset32 = 0x0aaa0000; 163 static const u64 kMIPS64_ShadowOffset64 = 1ULL << 37; 164 static const u64 kPPC64_ShadowOffset64 = 1ULL << 44; 165 static const u64 kSystemZ_ShadowOffset64 = 1ULL << 52; 166 static const u64 kFreeBSD_ShadowOffset32 = 1ULL << 30; // 0x40000000 167 static const u64 kFreeBSD_ShadowOffset64 = 1ULL << 46; // 0x400000000000 168 static const u64 kNetBSD_ShadowOffset32 = 1ULL << 30; // 0x40000000 169 static const u64 kNetBSD_ShadowOffset64 = 1ULL << 46; // 0x400000000000 170 static const u64 kWindowsShadowOffset32 = 3ULL << 28; // 0x30000000 171 172 static const u64 kMyriadMemoryOffset32 = 0x80000000ULL; 173 static const u64 kMyriadMemorySize32 = 0x20000000ULL; 174 static const u64 kMyriadMemoryEnd32 = 175 kMyriadMemoryOffset32 + kMyriadMemorySize32 - 1; 176 static const u64 kMyriadShadowOffset32 = 177 (kMyriadMemoryOffset32 + kMyriadMemorySize32 - 178 (kMyriadMemorySize32 >> kDefaultShadowScale)); 179 static const u64 kMyriadCacheBitMask32 = 0x40000000ULL; 180 181 #define SHADOW_SCALE kDefaultShadowScale 182 183 #if SANITIZER_FUCHSIA 184 # define SHADOW_OFFSET (0) 185 #elif SANITIZER_WORDSIZE == 32 186 # if SANITIZER_ANDROID 187 # define SHADOW_OFFSET __asan_shadow_memory_dynamic_address 188 # elif defined(__mips__) 189 # define SHADOW_OFFSET kMIPS32_ShadowOffset32 190 # elif SANITIZER_FREEBSD 191 # define SHADOW_OFFSET kFreeBSD_ShadowOffset32 192 # elif SANITIZER_NETBSD 193 # define SHADOW_OFFSET kNetBSD_ShadowOffset32 194 # elif SANITIZER_WINDOWS 195 # define SHADOW_OFFSET kWindowsShadowOffset32 196 # elif SANITIZER_IOS 197 # if SANITIZER_IOSSIM 198 # define SHADOW_OFFSET kIosSimShadowOffset32 199 # else 200 # define SHADOW_OFFSET kIosShadowOffset32 201 # endif 202 # elif SANITIZER_MYRIAD2 203 # define SHADOW_OFFSET kMyriadShadowOffset32 204 # else 205 # define SHADOW_OFFSET kDefaultShadowOffset32 206 # endif 207 #else 208 # if SANITIZER_IOS 209 # if SANITIZER_IOSSIM 210 # define SHADOW_OFFSET kIosSimShadowOffset64 211 # else 212 # define SHADOW_OFFSET __asan_shadow_memory_dynamic_address 213 # endif 214 # elif defined(__aarch64__) 215 # define SHADOW_OFFSET kAArch64_ShadowOffset64 216 # elif defined(__powerpc64__) 217 # define SHADOW_OFFSET kPPC64_ShadowOffset64 218 # elif defined(__s390x__) 219 # define SHADOW_OFFSET kSystemZ_ShadowOffset64 220 # elif SANITIZER_FREEBSD 221 # define SHADOW_OFFSET kFreeBSD_ShadowOffset64 222 # elif SANITIZER_NETBSD 223 # define SHADOW_OFFSET kNetBSD_ShadowOffset64 224 # elif SANITIZER_MAC 225 # define SHADOW_OFFSET kDefaultShadowOffset64 226 # elif defined(__mips64) 227 # define SHADOW_OFFSET kMIPS64_ShadowOffset64 228 # elif SANITIZER_WINDOWS64 229 # define SHADOW_OFFSET __asan_shadow_memory_dynamic_address 230 # else 231 # define SHADOW_OFFSET kDefaultShort64bitShadowOffset 232 # endif 233 #endif 234 235 #if SANITIZER_ANDROID && defined(__arm__) 236 # define ASAN_PREMAP_SHADOW 1 237 #else 238 # define ASAN_PREMAP_SHADOW 0 239 #endif 240 241 #define SHADOW_GRANULARITY (1ULL << SHADOW_SCALE) 242 243 #define DO_ASAN_MAPPING_PROFILE 0 // Set to 1 to profile the functions below. 244 245 #if DO_ASAN_MAPPING_PROFILE 246 # define PROFILE_ASAN_MAPPING() AsanMappingProfile[__LINE__]++; 247 #else 248 # define PROFILE_ASAN_MAPPING() 249 #endif 250 251 // If 1, all shadow boundaries are constants. 252 // Don't set to 1 other than for testing. 253 #define ASAN_FIXED_MAPPING 0 254 255 namespace __asan { 256 257 extern uptr AsanMappingProfile[]; 258 259 #if ASAN_FIXED_MAPPING 260 // Fixed mapping for 64-bit Linux. Mostly used for performance comparison 261 // with non-fixed mapping. As of r175253 (Feb 2013) the performance 262 // difference between fixed and non-fixed mapping is below the noise level. 263 static uptr kHighMemEnd = 0x7fffffffffffULL; 264 static uptr kMidMemBeg = 0x3000000000ULL; 265 static uptr kMidMemEnd = 0x4fffffffffULL; 266 #else 267 extern uptr kHighMemEnd, kMidMemBeg, kMidMemEnd; // Initialized in __asan_init. 268 #endif 269 270 } // namespace __asan 271 272 #if SANITIZER_MYRIAD2 273 #include "asan_mapping_myriad.h" 274 #else 275 #define MEM_TO_SHADOW(mem) (((mem) >> SHADOW_SCALE) + (SHADOW_OFFSET)) 276 277 #define kLowMemBeg 0 278 #define kLowMemEnd (SHADOW_OFFSET ? SHADOW_OFFSET - 1 : 0) 279 280 #define kLowShadowBeg SHADOW_OFFSET 281 #define kLowShadowEnd MEM_TO_SHADOW(kLowMemEnd) 282 283 #define kHighMemBeg (MEM_TO_SHADOW(kHighMemEnd) + 1) 284 285 #define kHighShadowBeg MEM_TO_SHADOW(kHighMemBeg) 286 #define kHighShadowEnd MEM_TO_SHADOW(kHighMemEnd) 287 288 # define kMidShadowBeg MEM_TO_SHADOW(kMidMemBeg) 289 # define kMidShadowEnd MEM_TO_SHADOW(kMidMemEnd) 290 291 // With the zero shadow base we can not actually map pages starting from 0. 292 // This constant is somewhat arbitrary. 293 #define kZeroBaseShadowStart 0 294 #define kZeroBaseMaxShadowStart (1 << 18) 295 296 #define kShadowGapBeg (kLowShadowEnd ? kLowShadowEnd + 1 \ 297 : kZeroBaseShadowStart) 298 #define kShadowGapEnd ((kMidMemBeg ? kMidShadowBeg : kHighShadowBeg) - 1) 299 300 #define kShadowGap2Beg (kMidMemBeg ? kMidShadowEnd + 1 : 0) 301 #define kShadowGap2End (kMidMemBeg ? kMidMemBeg - 1 : 0) 302 303 #define kShadowGap3Beg (kMidMemBeg ? kMidMemEnd + 1 : 0) 304 #define kShadowGap3End (kMidMemBeg ? kHighShadowBeg - 1 : 0) 305 306 namespace __asan { 307 308 static inline bool AddrIsInLowMem(uptr a) { 309 PROFILE_ASAN_MAPPING(); 310 return a <= kLowMemEnd; 311 } 312 313 static inline bool AddrIsInLowShadow(uptr a) { 314 PROFILE_ASAN_MAPPING(); 315 return a >= kLowShadowBeg && a <= kLowShadowEnd; 316 } 317 318 static inline bool AddrIsInMidMem(uptr a) { 319 PROFILE_ASAN_MAPPING(); 320 return kMidMemBeg && a >= kMidMemBeg && a <= kMidMemEnd; 321 } 322 323 static inline bool AddrIsInMidShadow(uptr a) { 324 PROFILE_ASAN_MAPPING(); 325 return kMidMemBeg && a >= kMidShadowBeg && a <= kMidShadowEnd; 326 } 327 328 static inline bool AddrIsInHighMem(uptr a) { 329 PROFILE_ASAN_MAPPING(); 330 return kHighMemBeg && a >= kHighMemBeg && a <= kHighMemEnd; 331 } 332 333 static inline bool AddrIsInHighShadow(uptr a) { 334 PROFILE_ASAN_MAPPING(); 335 return kHighMemBeg && a >= kHighShadowBeg && a <= kHighShadowEnd; 336 } 337 338 static inline bool AddrIsInShadowGap(uptr a) { 339 PROFILE_ASAN_MAPPING(); 340 if (kMidMemBeg) { 341 if (a <= kShadowGapEnd) 342 return SHADOW_OFFSET == 0 || a >= kShadowGapBeg; 343 return (a >= kShadowGap2Beg && a <= kShadowGap2End) || 344 (a >= kShadowGap3Beg && a <= kShadowGap3End); 345 } 346 // In zero-based shadow mode we treat addresses near zero as addresses 347 // in shadow gap as well. 348 if (SHADOW_OFFSET == 0) 349 return a <= kShadowGapEnd; 350 return a >= kShadowGapBeg && a <= kShadowGapEnd; 351 } 352 353 } // namespace __asan 354 355 #endif // SANITIZER_MYRIAD2 356 357 namespace __asan { 358 359 static inline bool AddrIsInMem(uptr a) { 360 PROFILE_ASAN_MAPPING(); 361 return AddrIsInLowMem(a) || AddrIsInMidMem(a) || AddrIsInHighMem(a) || 362 (flags()->protect_shadow_gap == 0 && AddrIsInShadowGap(a)); 363 } 364 365 static inline uptr MemToShadow(uptr p) { 366 PROFILE_ASAN_MAPPING(); 367 CHECK(AddrIsInMem(p)); 368 return MEM_TO_SHADOW(p); 369 } 370 371 static inline bool AddrIsInShadow(uptr a) { 372 PROFILE_ASAN_MAPPING(); 373 return AddrIsInLowShadow(a) || AddrIsInMidShadow(a) || AddrIsInHighShadow(a); 374 } 375 376 static inline bool AddrIsAlignedByGranularity(uptr a) { 377 PROFILE_ASAN_MAPPING(); 378 return (a & (SHADOW_GRANULARITY - 1)) == 0; 379 } 380 381 static inline bool AddressIsPoisoned(uptr a) { 382 PROFILE_ASAN_MAPPING(); 383 if (SANITIZER_MYRIAD2 && !AddrIsInMem(a) && !AddrIsInShadow(a)) 384 return false; 385 const uptr kAccessSize = 1; 386 u8 *shadow_address = (u8*)MEM_TO_SHADOW(a); 387 s8 shadow_value = *shadow_address; 388 if (shadow_value) { 389 u8 last_accessed_byte = (a & (SHADOW_GRANULARITY - 1)) 390 + kAccessSize - 1; 391 return (last_accessed_byte >= shadow_value); 392 } 393 return false; 394 } 395 396 // Must be after all calls to PROFILE_ASAN_MAPPING(). 397 static const uptr kAsanMappingProfileSize = __LINE__; 398 399 } // namespace __asan 400 401 #endif // ASAN_MAPPING_H 402
Indexes created Sun Sep 21 20:09:37 GMT 2025