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