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-exception 6 // 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_H 14 #define ASAN_MAPPING_H 15 16 #include "asan_internal.h" 17 18 // The full explanation of the memory mapping could be found here: 19 // https://github.com/google/sanitizers/wiki/AddressSanitizerAlgorithm 20 // 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 between 34 // 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 machine 53 // (addresses starting with 0xc0000000 are reserved 54 // 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/AArch64 (39-bit VMA) mapping: 76 // || `[0x2000000000, 0x7fffffffff]` || highmem || 77 // || `[0x1400000000, 0x1fffffffff]` || highshadow || 78 // || `[0x1200000000, 0x13ffffffff]` || shadowgap || 79 // || `[0x1000000000, 0x11ffffffff]` || lowshadow || 80 // || `[0x0000000000, 0x0fffffffff]` || lowmem || 81 // 82 // RISC-V has only 38 bits for task size 83 // Low mem size is set with kRiscv64_ShadowOffset64 in 84 // compiler-rt/lib/asan/asan_allocator.h and in 85 // llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp with 86 // kRiscv64_ShadowOffset64, High mem top border is set with 87 // GetMaxVirtualAddress() in 88 // compiler-rt/lib/sanitizer_common/sanitizer_linux.cpp 89 // Default Linux/RISCV64 Sv39/Sv48 mapping: 90 // || `[0x000820000000, 0x003fffffffff]` || HighMem || 91 // || `[0x000124000000, 0x00081fffffff]` || HighShadow || 92 // || `[0x000024000000, 0x000123ffffff]` || ShadowGap || 93 // || `[0x000020000000, 0x000023ffffff]` || LowShadow || 94 // || `[0x000000000000, 0x00001fffffff]` || LowMem || 95 // 96 // Default Linux/AArch64 (42-bit VMA) mapping: 97 // || `[0x10000000000, 0x3ffffffffff]` || highmem || 98 // || `[0x0a000000000, 0x0ffffffffff]` || highshadow || 99 // || `[0x09000000000, 0x09fffffffff]` || shadowgap || 100 // || `[0x08000000000, 0x08fffffffff]` || lowshadow || 101 // || `[0x00000000000, 0x07fffffffff]` || lowmem || 102 // 103 // Default Linux/S390 mapping: 104 // || `[0x30000000, 0x7fffffff]` || HighMem || 105 // || `[0x26000000, 0x2fffffff]` || HighShadow || 106 // || `[0x24000000, 0x25ffffff]` || ShadowGap || 107 // || `[0x20000000, 0x23ffffff]` || LowShadow || 108 // || `[0x00000000, 0x1fffffff]` || LowMem || 109 // 110 // Default Linux/SystemZ mapping: 111 // || `[0x14000000000000, 0x1fffffffffffff]` || HighMem || 112 // || `[0x12800000000000, 0x13ffffffffffff]` || HighShadow || 113 // || `[0x12000000000000, 0x127fffffffffff]` || ShadowGap || 114 // || `[0x10000000000000, 0x11ffffffffffff]` || LowShadow || 115 // || `[0x00000000000000, 0x0fffffffffffff]` || LowMem || 116 // 117 // Default Linux/SPARC64 (52-bit VMA) mapping: 118 // || `[0x8000000000000, 0xfffffffffffff]` || HighMem || 119 // || `[0x1080000000000, 0x207ffffffffff]` || HighShadow || 120 // || `[0x0090000000000, 0x107ffffffffff]` || ShadowGap || 121 // || `[0x0080000000000, 0x008ffffffffff]` || LowShadow || 122 // || `[0x0000000000000, 0x007ffffffffff]` || LowMem || 123 // 124 // Shadow mapping on FreeBSD/x86-64 with SHADOW_OFFSET == 0x400000000000: 125 // || `[0x500000000000, 0x7fffffffffff]` || HighMem || 126 // || `[0x4a0000000000, 0x4fffffffffff]` || HighShadow || 127 // || `[0x480000000000, 0x49ffffffffff]` || ShadowGap || 128 // || `[0x400000000000, 0x47ffffffffff]` || LowShadow || 129 // || `[0x000000000000, 0x3fffffffffff]` || LowMem || 130 // 131 // Shadow mapping on FreeBSD/i386 with SHADOW_OFFSET == 0x40000000: 132 // || `[0x60000000, 0xffffffff]` || HighMem || 133 // || `[0x4c000000, 0x5fffffff]` || HighShadow || 134 // || `[0x48000000, 0x4bffffff]` || ShadowGap || 135 // || `[0x40000000, 0x47ffffff]` || LowShadow || 136 // || `[0x00000000, 0x3fffffff]` || LowMem || 137 // 138 // Shadow mapping on NetBSD/x86-64 with SHADOW_OFFSET == 0x400000000000: 139 // || `[0x4feffffffe01, 0x7f7ffffff000]` || HighMem || 140 // || `[0x49fdffffffc0, 0x4feffffffe00]` || HighShadow || 141 // || `[0x480000000000, 0x49fdffffffbf]` || ShadowGap || 142 // || `[0x400000000000, 0x47ffffffffff]` || LowShadow || 143 // || `[0x000000000000, 0x3fffffffffff]` || LowMem || 144 // 145 // Shadow mapping on NetBSD/i386 with SHADOW_OFFSET == 0x40000000: 146 // || `[0x60000000, 0xfffff000]` || HighMem || 147 // || `[0x4c000000, 0x5fffffff]` || HighShadow || 148 // || `[0x48000000, 0x4bffffff]` || ShadowGap || 149 // || `[0x40000000, 0x47ffffff]` || LowShadow || 150 // || `[0x00000000, 0x3fffffff]` || LowMem || 151 // 152 // Default Windows/i386 mapping: 153 // (the exact location of HighShadow/HighMem may vary depending 154 // on WoW64, /LARGEADDRESSAWARE, etc). 155 // || `[0x50000000, 0xffffffff]` || HighMem || 156 // || `[0x3a000000, 0x4fffffff]` || HighShadow || 157 // || `[0x36000000, 0x39ffffff]` || ShadowGap || 158 // || `[0x30000000, 0x35ffffff]` || LowShadow || 159 // || `[0x00000000, 0x2fffffff]` || LowMem || 160 // 161 // Shadow mapping on Myriad2 (for shadow scale 5): 162 // || `[0x9ff80000, 0x9fffffff]` || ShadowGap || 163 // || `[0x9f000000, 0x9ff7ffff]` || LowShadow || 164 // || `[0x80000000, 0x9effffff]` || LowMem || 165 // || `[0x00000000, 0x7fffffff]` || Ignored || 166 167 #if defined(ASAN_SHADOW_SCALE) 168 static const u64 kDefaultShadowScale = ASAN_SHADOW_SCALE; 169 #else 170 static const u64 kDefaultShadowScale = SANITIZER_MYRIAD2 ? 5 : 3; 171 #endif 172 static const u64 kDefaultShadowSentinel = ~(uptr)0; 173 static const u64 kDefaultShadowOffset32 = 1ULL << 29; // 0x20000000 174 static const u64 kDefaultShadowOffset64 = 1ULL << 44; 175 static const u64 kDefaultShort64bitShadowOffset = 176 0x7FFFFFFF & (~0xFFFULL << kDefaultShadowScale); // < 2G. 177 static const u64 kAArch64_ShadowOffset64 = 1ULL << 36; 178 static const u64 kRiscv64_ShadowOffset64 = 0x20000000; 179 static const u64 kMIPS32_ShadowOffset32 = 0x0aaa0000; 180 static const u64 kMIPS64_ShadowOffset64 = 1ULL << 37; 181 static const u64 kPPC64_ShadowOffset64 = 1ULL << 44; 182 static const u64 kSystemZ_ShadowOffset64 = 1ULL << 52; 183 static const u64 kSPARC64_ShadowOffset64 = 1ULL << 43; // 0x80000000000 184 static const u64 kFreeBSD_ShadowOffset32 = 1ULL << 30; // 0x40000000 185 static const u64 kFreeBSD_ShadowOffset64 = 1ULL << 46; // 0x400000000000 186 static const u64 kNetBSD_ShadowOffset32 = 1ULL << 30; // 0x40000000 187 static const u64 kNetBSD_ShadowOffset64 = 1ULL << 46; // 0x400000000000 188 static const u64 kWindowsShadowOffset32 = 3ULL << 28; // 0x30000000 189 190 static const u64 kMyriadMemoryOffset32 = 0x80000000ULL; 191 static const u64 kMyriadMemorySize32 = 0x20000000ULL; 192 static const u64 kMyriadMemoryEnd32 = 193 kMyriadMemoryOffset32 + kMyriadMemorySize32 - 1; 194 static const u64 kMyriadShadowOffset32 = 195 (kMyriadMemoryOffset32 + kMyriadMemorySize32 - 196 (kMyriadMemorySize32 >> kDefaultShadowScale)); 197 static const u64 kMyriadCacheBitMask32 = 0x40000000ULL; 198 199 #define SHADOW_SCALE kDefaultShadowScale 200 201 #if SANITIZER_FUCHSIA 202 # define SHADOW_OFFSET (0) 203 #elif SANITIZER_WORDSIZE == 32 204 # if SANITIZER_ANDROID 205 # define SHADOW_OFFSET __asan_shadow_memory_dynamic_address 206 # elif defined(__mips__) 207 # define SHADOW_OFFSET kMIPS32_ShadowOffset32 208 # elif SANITIZER_FREEBSD 209 # define SHADOW_OFFSET kFreeBSD_ShadowOffset32 210 # elif SANITIZER_NETBSD 211 # define SHADOW_OFFSET kNetBSD_ShadowOffset32 212 # elif SANITIZER_WINDOWS 213 # define SHADOW_OFFSET kWindowsShadowOffset32 214 # elif SANITIZER_IOS 215 # define SHADOW_OFFSET __asan_shadow_memory_dynamic_address 216 # elif SANITIZER_MYRIAD2 217 # define SHADOW_OFFSET kMyriadShadowOffset32 218 # else 219 # define SHADOW_OFFSET kDefaultShadowOffset32 220 # endif 221 #else 222 # if SANITIZER_IOS 223 # define SHADOW_OFFSET __asan_shadow_memory_dynamic_address 224 # elif SANITIZER_MAC && defined(__aarch64__) 225 # define SHADOW_OFFSET __asan_shadow_memory_dynamic_address 226 #elif SANITIZER_RISCV64 227 #define SHADOW_OFFSET kRiscv64_ShadowOffset64 228 # elif defined(__aarch64__) 229 # define SHADOW_OFFSET kAArch64_ShadowOffset64 230 # elif defined(__powerpc64__) 231 # define SHADOW_OFFSET kPPC64_ShadowOffset64 232 # elif defined(__s390x__) 233 # define SHADOW_OFFSET kSystemZ_ShadowOffset64 234 # elif SANITIZER_FREEBSD 235 # define SHADOW_OFFSET kFreeBSD_ShadowOffset64 236 # elif SANITIZER_NETBSD 237 # define SHADOW_OFFSET kNetBSD_ShadowOffset64 238 # elif SANITIZER_MAC 239 # define SHADOW_OFFSET kDefaultShadowOffset64 240 # elif defined(__mips64) 241 # define SHADOW_OFFSET kMIPS64_ShadowOffset64 242 #elif defined(__sparc__) 243 #define SHADOW_OFFSET kSPARC64_ShadowOffset64 244 # elif SANITIZER_WINDOWS64 245 # define SHADOW_OFFSET __asan_shadow_memory_dynamic_address 246 # else 247 # define SHADOW_OFFSET kDefaultShort64bitShadowOffset 248 # endif 249 #endif 250 251 #if SANITIZER_ANDROID && defined(__arm__) 252 # define ASAN_PREMAP_SHADOW 1 253 #else 254 # define ASAN_PREMAP_SHADOW 0 255 #endif 256 257 #define SHADOW_GRANULARITY (1ULL << SHADOW_SCALE) 258 259 #define DO_ASAN_MAPPING_PROFILE 0 // Set to 1 to profile the functions below. 260 261 #if DO_ASAN_MAPPING_PROFILE 262 # define PROFILE_ASAN_MAPPING() AsanMappingProfile[__LINE__]++; 263 #else 264 # define PROFILE_ASAN_MAPPING() 265 #endif 266 267 // If 1, all shadow boundaries are constants. 268 // Don't set to 1 other than for testing. 269 #define ASAN_FIXED_MAPPING 0 270 271 namespace __asan { 272 273 extern uptr AsanMappingProfile[]; 274 275 #if ASAN_FIXED_MAPPING 276 // Fixed mapping for 64-bit Linux. Mostly used for performance comparison 277 // with non-fixed mapping. As of r175253 (Feb 2013) the performance 278 // difference between fixed and non-fixed mapping is below the noise level. 279 static uptr kHighMemEnd = 0x7fffffffffffULL; 280 static uptr kMidMemBeg = 0x3000000000ULL; 281 static uptr kMidMemEnd = 0x4fffffffffULL; 282 #else 283 extern uptr kHighMemEnd, kMidMemBeg, kMidMemEnd; // Initialized in __asan_init. 284 #endif 285 286 } // namespace __asan 287 288 #if SANITIZER_MYRIAD2 289 #include "asan_mapping_myriad.h" 290 #elif defined(__sparc__) && SANITIZER_WORDSIZE == 64 291 #include "asan_mapping_sparc64.h" 292 #else 293 #define MEM_TO_SHADOW(mem) (((mem) >> SHADOW_SCALE) + (SHADOW_OFFSET)) 294 295 #define kLowMemBeg 0 296 #define kLowMemEnd (SHADOW_OFFSET ? SHADOW_OFFSET - 1 : 0) 297 298 #define kLowShadowBeg SHADOW_OFFSET 299 #define kLowShadowEnd MEM_TO_SHADOW(kLowMemEnd) 300 301 #define kHighMemBeg (MEM_TO_SHADOW(kHighMemEnd) + 1) 302 303 #define kHighShadowBeg MEM_TO_SHADOW(kHighMemBeg) 304 #define kHighShadowEnd MEM_TO_SHADOW(kHighMemEnd) 305 306 # define kMidShadowBeg MEM_TO_SHADOW(kMidMemBeg) 307 # define kMidShadowEnd MEM_TO_SHADOW(kMidMemEnd) 308 309 // With the zero shadow base we can not actually map pages starting from 0. 310 // This constant is somewhat arbitrary. 311 #define kZeroBaseShadowStart 0 312 #define kZeroBaseMaxShadowStart (1 << 18) 313 314 #define kShadowGapBeg (kLowShadowEnd ? kLowShadowEnd + 1 \ 315 : kZeroBaseShadowStart) 316 #define kShadowGapEnd ((kMidMemBeg ? kMidShadowBeg : kHighShadowBeg) - 1) 317 318 #define kShadowGap2Beg (kMidMemBeg ? kMidShadowEnd + 1 : 0) 319 #define kShadowGap2End (kMidMemBeg ? kMidMemBeg - 1 : 0) 320 321 #define kShadowGap3Beg (kMidMemBeg ? kMidMemEnd + 1 : 0) 322 #define kShadowGap3End (kMidMemBeg ? kHighShadowBeg - 1 : 0) 323 324 namespace __asan { 325 326 static inline bool AddrIsInLowMem(uptr a) { 327 PROFILE_ASAN_MAPPING(); 328 return a <= kLowMemEnd; 329 } 330 331 static inline bool AddrIsInLowShadow(uptr a) { 332 PROFILE_ASAN_MAPPING(); 333 return a >= kLowShadowBeg && a <= kLowShadowEnd; 334 } 335 336 static inline bool AddrIsInMidMem(uptr a) { 337 PROFILE_ASAN_MAPPING(); 338 return kMidMemBeg && a >= kMidMemBeg && a <= kMidMemEnd; 339 } 340 341 static inline bool AddrIsInMidShadow(uptr a) { 342 PROFILE_ASAN_MAPPING(); 343 return kMidMemBeg && a >= kMidShadowBeg && a <= kMidShadowEnd; 344 } 345 346 static inline bool AddrIsInHighMem(uptr a) { 347 PROFILE_ASAN_MAPPING(); 348 return kHighMemBeg && a >= kHighMemBeg && a <= kHighMemEnd; 349 } 350 351 static inline bool AddrIsInHighShadow(uptr a) { 352 PROFILE_ASAN_MAPPING(); 353 return kHighMemBeg && a >= kHighShadowBeg && a <= kHighShadowEnd; 354 } 355 356 static inline bool AddrIsInShadowGap(uptr a) { 357 PROFILE_ASAN_MAPPING(); 358 if (kMidMemBeg) { 359 if (a <= kShadowGapEnd) 360 return SHADOW_OFFSET == 0 || a >= kShadowGapBeg; 361 return (a >= kShadowGap2Beg && a <= kShadowGap2End) || 362 (a >= kShadowGap3Beg && a <= kShadowGap3End); 363 } 364 // In zero-based shadow mode we treat addresses near zero as addresses 365 // in shadow gap as well. 366 if (SHADOW_OFFSET == 0) 367 return a <= kShadowGapEnd; 368 return a >= kShadowGapBeg && a <= kShadowGapEnd; 369 } 370 371 } // namespace __asan 372 373 #endif // SANITIZER_MYRIAD2 374 375 namespace __asan { 376 377 static inline uptr MemToShadowSize(uptr size) { return size >> SHADOW_SCALE; } 378 379 static inline bool AddrIsInMem(uptr a) { 380 PROFILE_ASAN_MAPPING(); 381 return AddrIsInLowMem(a) || AddrIsInMidMem(a) || AddrIsInHighMem(a) || 382 (flags()->protect_shadow_gap == 0 && AddrIsInShadowGap(a)); 383 } 384 385 static inline uptr MemToShadow(uptr p) { 386 PROFILE_ASAN_MAPPING(); 387 CHECK(AddrIsInMem(p)); 388 return MEM_TO_SHADOW(p); 389 } 390 391 static inline bool AddrIsInShadow(uptr a) { 392 PROFILE_ASAN_MAPPING(); 393 return AddrIsInLowShadow(a) || AddrIsInMidShadow(a) || AddrIsInHighShadow(a); 394 } 395 396 static inline bool AddrIsAlignedByGranularity(uptr a) { 397 PROFILE_ASAN_MAPPING(); 398 return (a & (SHADOW_GRANULARITY - 1)) == 0; 399 } 400 401 static inline bool AddressIsPoisoned(uptr a) { 402 PROFILE_ASAN_MAPPING(); 403 if (SANITIZER_MYRIAD2 && !AddrIsInMem(a) && !AddrIsInShadow(a)) 404 return false; 405 const uptr kAccessSize = 1; 406 u8 *shadow_address = (u8*)MEM_TO_SHADOW(a); 407 s8 shadow_value = *shadow_address; 408 if (shadow_value) { 409 u8 last_accessed_byte = (a & (SHADOW_GRANULARITY - 1)) 410 + kAccessSize - 1; 411 return (last_accessed_byte >= shadow_value); 412 } 413 return false; 414 } 415 416 // Must be after all calls to PROFILE_ASAN_MAPPING(). 417 static const uptr kAsanMappingProfileSize = __LINE__; 418 419 } // namespace __asan 420 421 #endif // ASAN_MAPPING_H 422