1 //===-- sanitizer_fuchsia.cpp ---------------------------------------------===// 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 shared between AddressSanitizer and other sanitizer 10 // run-time libraries and implements Fuchsia-specific functions from 11 // sanitizer_common.h. 12 //===----------------------------------------------------------------------===// 13 14 #include "sanitizer_fuchsia.h" 15 #if SANITIZER_FUCHSIA 16 17 # include <pthread.h> 18 # include <stdlib.h> 19 # include <unistd.h> 20 # include <zircon/errors.h> 21 # include <zircon/process.h> 22 # include <zircon/syscalls.h> 23 # include <zircon/utc.h> 24 25 # include "sanitizer_common.h" 26 # include "sanitizer_interface_internal.h" 27 # include "sanitizer_libc.h" 28 # include "sanitizer_mutex.h" 29 30 namespace __sanitizer { 31 32 void NORETURN internal__exit(int exitcode) { _zx_process_exit(exitcode); } 33 34 uptr internal_sched_yield() { 35 zx_status_t status = _zx_thread_legacy_yield(0u); 36 CHECK_EQ(status, ZX_OK); 37 return 0; // Why doesn't this return void? 38 } 39 40 void internal_usleep(u64 useconds) { 41 zx_status_t status = _zx_nanosleep(_zx_deadline_after(ZX_USEC(useconds))); 42 CHECK_EQ(status, ZX_OK); 43 } 44 45 u64 NanoTime() { 46 zx_handle_t utc_clock = _zx_utc_reference_get(); 47 CHECK_NE(utc_clock, ZX_HANDLE_INVALID); 48 zx_time_t time; 49 zx_status_t status = _zx_clock_read(utc_clock, &time); 50 CHECK_EQ(status, ZX_OK); 51 return time; 52 } 53 54 u64 MonotonicNanoTime() { return _zx_clock_get_monotonic(); } 55 56 uptr internal_getpid() { 57 zx_info_handle_basic_t info; 58 zx_status_t status = 59 _zx_object_get_info(_zx_process_self(), ZX_INFO_HANDLE_BASIC, &info, 60 sizeof(info), NULL, NULL); 61 CHECK_EQ(status, ZX_OK); 62 uptr pid = static_cast<uptr>(info.koid); 63 CHECK_EQ(pid, info.koid); 64 return pid; 65 } 66 67 int internal_dlinfo(void *handle, int request, void *p) { UNIMPLEMENTED(); } 68 69 uptr GetThreadSelf() { return reinterpret_cast<uptr>(thrd_current()); } 70 71 tid_t GetTid() { return GetThreadSelf(); } 72 73 void Abort() { abort(); } 74 75 int Atexit(void (*function)(void)) { return atexit(function); } 76 77 void GetThreadStackTopAndBottom(bool, uptr *stack_top, uptr *stack_bottom) { 78 pthread_attr_t attr; 79 CHECK_EQ(pthread_getattr_np(pthread_self(), &attr), 0); 80 void *base; 81 size_t size; 82 CHECK_EQ(pthread_attr_getstack(&attr, &base, &size), 0); 83 CHECK_EQ(pthread_attr_destroy(&attr), 0); 84 85 *stack_bottom = reinterpret_cast<uptr>(base); 86 *stack_top = *stack_bottom + size; 87 } 88 89 void InitializePlatformEarly() {} 90 void CheckASLR() {} 91 void CheckMPROTECT() {} 92 void PlatformPrepareForSandboxing(void *args) {} 93 void DisableCoreDumperIfNecessary() {} 94 void InstallDeadlySignalHandlers(SignalHandlerType handler) {} 95 void SetAlternateSignalStack() {} 96 void UnsetAlternateSignalStack() {} 97 98 bool SignalContext::IsStackOverflow() const { return false; } 99 void SignalContext::DumpAllRegisters(void *context) { UNIMPLEMENTED(); } 100 const char *SignalContext::Describe() const { UNIMPLEMENTED(); } 101 102 void FutexWait(atomic_uint32_t *p, u32 cmp) { 103 zx_status_t status = _zx_futex_wait(reinterpret_cast<zx_futex_t *>(p), cmp, 104 ZX_HANDLE_INVALID, ZX_TIME_INFINITE); 105 if (status != ZX_ERR_BAD_STATE) // Normal race. 106 CHECK_EQ(status, ZX_OK); 107 } 108 109 void FutexWake(atomic_uint32_t *p, u32 count) { 110 zx_status_t status = _zx_futex_wake(reinterpret_cast<zx_futex_t *>(p), count); 111 CHECK_EQ(status, ZX_OK); 112 } 113 114 uptr GetPageSize() { return _zx_system_get_page_size(); } 115 116 uptr GetMmapGranularity() { return _zx_system_get_page_size(); } 117 118 sanitizer_shadow_bounds_t ShadowBounds; 119 120 void InitShadowBounds() { ShadowBounds = __sanitizer_shadow_bounds(); } 121 122 uptr GetMaxUserVirtualAddress() { 123 InitShadowBounds(); 124 return ShadowBounds.memory_limit - 1; 125 } 126 127 uptr GetMaxVirtualAddress() { return GetMaxUserVirtualAddress(); } 128 129 bool ErrorIsOOM(error_t err) { return err == ZX_ERR_NO_MEMORY; } 130 131 // For any sanitizer internal that needs to map something which can be unmapped 132 // later, first attempt to map to a pre-allocated VMAR. This helps reduce 133 // fragmentation from many small anonymous mmap calls. A good value for this 134 // VMAR size would be the total size of your typical sanitizer internal objects 135 // allocated in an "average" process lifetime. Examples of this include: 136 // FakeStack, LowLevelAllocator mappings, TwoLevelMap, InternalMmapVector, 137 // StackStore, CreateAsanThread, etc. 138 // 139 // This is roughly equal to the total sum of sanitizer internal mappings for a 140 // large test case. 141 constexpr size_t kSanitizerHeapVmarSize = 13ULL << 20; 142 static zx_handle_t gSanitizerHeapVmar = ZX_HANDLE_INVALID; 143 144 static zx_status_t GetSanitizerHeapVmar(zx_handle_t *vmar) { 145 zx_status_t status = ZX_OK; 146 if (gSanitizerHeapVmar == ZX_HANDLE_INVALID) { 147 CHECK_EQ(kSanitizerHeapVmarSize % GetPageSizeCached(), 0); 148 uintptr_t base; 149 status = _zx_vmar_allocate( 150 _zx_vmar_root_self(), 151 ZX_VM_CAN_MAP_READ | ZX_VM_CAN_MAP_WRITE | ZX_VM_CAN_MAP_SPECIFIC, 0, 152 kSanitizerHeapVmarSize, &gSanitizerHeapVmar, &base); 153 } 154 *vmar = gSanitizerHeapVmar; 155 if (status == ZX_OK) 156 CHECK_NE(gSanitizerHeapVmar, ZX_HANDLE_INVALID); 157 return status; 158 } 159 160 static zx_status_t TryVmoMapSanitizerVmar(zx_vm_option_t options, 161 size_t vmar_offset, zx_handle_t vmo, 162 size_t size, uintptr_t *addr, 163 zx_handle_t *vmar_used = nullptr) { 164 zx_handle_t vmar; 165 zx_status_t status = GetSanitizerHeapVmar(&vmar); 166 if (status != ZX_OK) 167 return status; 168 169 status = _zx_vmar_map(gSanitizerHeapVmar, options, vmar_offset, vmo, 170 /*vmo_offset=*/0, size, addr); 171 if (vmar_used) 172 *vmar_used = gSanitizerHeapVmar; 173 if (status == ZX_ERR_NO_RESOURCES || status == ZX_ERR_INVALID_ARGS) { 174 // This means there's no space in the heap VMAR, so fallback to the root 175 // VMAR. 176 status = _zx_vmar_map(_zx_vmar_root_self(), options, vmar_offset, vmo, 177 /*vmo_offset=*/0, size, addr); 178 if (vmar_used) 179 *vmar_used = _zx_vmar_root_self(); 180 } 181 182 return status; 183 } 184 185 static void *DoAnonymousMmapOrDie(uptr size, const char *mem_type, 186 bool raw_report, bool die_for_nomem) { 187 size = RoundUpTo(size, GetPageSize()); 188 189 zx_handle_t vmo; 190 zx_status_t status = _zx_vmo_create(size, 0, &vmo); 191 if (status != ZX_OK) { 192 if (status != ZX_ERR_NO_MEMORY || die_for_nomem) 193 ReportMmapFailureAndDie(size, mem_type, "zx_vmo_create", status, 194 raw_report); 195 return nullptr; 196 } 197 _zx_object_set_property(vmo, ZX_PROP_NAME, mem_type, 198 internal_strlen(mem_type)); 199 200 uintptr_t addr; 201 status = TryVmoMapSanitizerVmar(ZX_VM_PERM_READ | ZX_VM_PERM_WRITE, 202 /*vmar_offset=*/0, vmo, size, &addr); 203 _zx_handle_close(vmo); 204 205 if (status != ZX_OK) { 206 if (status != ZX_ERR_NO_MEMORY || die_for_nomem) 207 ReportMmapFailureAndDie(size, mem_type, "zx_vmar_map", status, 208 raw_report); 209 return nullptr; 210 } 211 212 IncreaseTotalMmap(size); 213 214 return reinterpret_cast<void *>(addr); 215 } 216 217 void *MmapOrDie(uptr size, const char *mem_type, bool raw_report) { 218 return DoAnonymousMmapOrDie(size, mem_type, raw_report, true); 219 } 220 221 void *MmapNoReserveOrDie(uptr size, const char *mem_type) { 222 return MmapOrDie(size, mem_type); 223 } 224 225 void *MmapOrDieOnFatalError(uptr size, const char *mem_type) { 226 return DoAnonymousMmapOrDie(size, mem_type, false, false); 227 } 228 229 uptr ReservedAddressRange::Init(uptr init_size, const char *name, 230 uptr fixed_addr) { 231 init_size = RoundUpTo(init_size, GetPageSize()); 232 DCHECK_EQ(os_handle_, ZX_HANDLE_INVALID); 233 uintptr_t base; 234 zx_handle_t vmar; 235 zx_status_t status = _zx_vmar_allocate( 236 _zx_vmar_root_self(), 237 ZX_VM_CAN_MAP_READ | ZX_VM_CAN_MAP_WRITE | ZX_VM_CAN_MAP_SPECIFIC, 0, 238 init_size, &vmar, &base); 239 if (status != ZX_OK) 240 ReportMmapFailureAndDie(init_size, name, "zx_vmar_allocate", status); 241 base_ = reinterpret_cast<void *>(base); 242 size_ = init_size; 243 name_ = name; 244 os_handle_ = vmar; 245 246 return reinterpret_cast<uptr>(base_); 247 } 248 249 static uptr DoMmapFixedOrDie(zx_handle_t vmar, uptr fixed_addr, uptr map_size, 250 void *base, const char *name, bool die_for_nomem) { 251 uptr offset = fixed_addr - reinterpret_cast<uptr>(base); 252 map_size = RoundUpTo(map_size, GetPageSize()); 253 zx_handle_t vmo; 254 zx_status_t status = _zx_vmo_create(map_size, 0, &vmo); 255 if (status != ZX_OK) { 256 if (status != ZX_ERR_NO_MEMORY || die_for_nomem) 257 ReportMmapFailureAndDie(map_size, name, "zx_vmo_create", status); 258 return 0; 259 } 260 _zx_object_set_property(vmo, ZX_PROP_NAME, name, internal_strlen(name)); 261 DCHECK_GE(base + size_, map_size + offset); 262 uintptr_t addr; 263 264 status = 265 _zx_vmar_map(vmar, ZX_VM_PERM_READ | ZX_VM_PERM_WRITE | ZX_VM_SPECIFIC, 266 offset, vmo, 0, map_size, &addr); 267 _zx_handle_close(vmo); 268 if (status != ZX_OK) { 269 if (status != ZX_ERR_NO_MEMORY || die_for_nomem) { 270 ReportMmapFailureAndDie(map_size, name, "zx_vmar_map", status); 271 } 272 return 0; 273 } 274 IncreaseTotalMmap(map_size); 275 return addr; 276 } 277 278 uptr ReservedAddressRange::Map(uptr fixed_addr, uptr map_size, 279 const char *name) { 280 return DoMmapFixedOrDie(os_handle_, fixed_addr, map_size, base_, 281 name ? name : name_, false); 282 } 283 284 uptr ReservedAddressRange::MapOrDie(uptr fixed_addr, uptr map_size, 285 const char *name) { 286 return DoMmapFixedOrDie(os_handle_, fixed_addr, map_size, base_, 287 name ? name : name_, true); 288 } 289 290 void UnmapOrDieVmar(void *addr, uptr size, zx_handle_t target_vmar, 291 bool raw_report) { 292 if (!addr || !size) 293 return; 294 size = RoundUpTo(size, GetPageSize()); 295 296 zx_status_t status = 297 _zx_vmar_unmap(target_vmar, reinterpret_cast<uintptr_t>(addr), size); 298 if (status == ZX_ERR_INVALID_ARGS && target_vmar == gSanitizerHeapVmar) { 299 // If there wasn't any space in the heap vmar, the fallback was the root 300 // vmar. 301 status = _zx_vmar_unmap(_zx_vmar_root_self(), 302 reinterpret_cast<uintptr_t>(addr), size); 303 } 304 if (status != ZX_OK) 305 ReportMunmapFailureAndDie(addr, size, status, raw_report); 306 307 DecreaseTotalMmap(size); 308 } 309 310 void ReservedAddressRange::Unmap(uptr addr, uptr size) { 311 CHECK_LE(size, size_); 312 const zx_handle_t vmar = static_cast<zx_handle_t>(os_handle_); 313 if (addr == reinterpret_cast<uptr>(base_)) { 314 if (size == size_) { 315 // Destroying the vmar effectively unmaps the whole mapping. 316 _zx_vmar_destroy(vmar); 317 _zx_handle_close(vmar); 318 os_handle_ = static_cast<uptr>(ZX_HANDLE_INVALID); 319 DecreaseTotalMmap(size); 320 return; 321 } 322 } else { 323 CHECK_EQ(addr + size, reinterpret_cast<uptr>(base_) + size_); 324 } 325 // Partial unmapping does not affect the fact that the initial range is still 326 // reserved, and the resulting unmapped memory can't be reused. 327 UnmapOrDieVmar(reinterpret_cast<void *>(addr), size, vmar, 328 /*raw_report=*/false); 329 } 330 331 // This should never be called. 332 void *MmapFixedNoAccess(uptr fixed_addr, uptr size, const char *name) { 333 UNIMPLEMENTED(); 334 } 335 336 bool MprotectNoAccess(uptr addr, uptr size) { 337 return _zx_vmar_protect(_zx_vmar_root_self(), 0, addr, size) == ZX_OK; 338 } 339 340 bool MprotectReadOnly(uptr addr, uptr size) { 341 return _zx_vmar_protect(_zx_vmar_root_self(), ZX_VM_PERM_READ, addr, size) == 342 ZX_OK; 343 } 344 345 bool MprotectReadWrite(uptr addr, uptr size) { 346 return _zx_vmar_protect(_zx_vmar_root_self(), 347 ZX_VM_PERM_READ | ZX_VM_PERM_WRITE, addr, 348 size) == ZX_OK; 349 } 350 351 void *MmapAlignedOrDieOnFatalError(uptr size, uptr alignment, 352 const char *mem_type) { 353 CHECK_GE(size, GetPageSize()); 354 CHECK(IsPowerOfTwo(size)); 355 CHECK(IsPowerOfTwo(alignment)); 356 357 zx_handle_t vmo; 358 zx_status_t status = _zx_vmo_create(size, 0, &vmo); 359 if (status != ZX_OK) { 360 if (status != ZX_ERR_NO_MEMORY) 361 ReportMmapFailureAndDie(size, mem_type, "zx_vmo_create", status, false); 362 return nullptr; 363 } 364 _zx_object_set_property(vmo, ZX_PROP_NAME, mem_type, 365 internal_strlen(mem_type)); 366 367 // Map a larger size to get a chunk of address space big enough that 368 // it surely contains an aligned region of the requested size. Then 369 // overwrite the aligned middle portion with a mapping from the 370 // beginning of the VMO, and unmap the excess before and after. 371 size_t map_size = size + alignment; 372 uintptr_t addr; 373 zx_handle_t vmar_used; 374 status = TryVmoMapSanitizerVmar(ZX_VM_PERM_READ | ZX_VM_PERM_WRITE, 375 /*vmar_offset=*/0, vmo, map_size, &addr, 376 &vmar_used); 377 if (status == ZX_OK) { 378 uintptr_t map_addr = addr; 379 uintptr_t map_end = map_addr + map_size; 380 addr = RoundUpTo(map_addr, alignment); 381 uintptr_t end = addr + size; 382 if (addr != map_addr) { 383 zx_info_vmar_t info; 384 status = _zx_object_get_info(vmar_used, ZX_INFO_VMAR, &info, sizeof(info), 385 NULL, NULL); 386 if (status == ZX_OK) { 387 uintptr_t new_addr; 388 status = _zx_vmar_map( 389 vmar_used, 390 ZX_VM_PERM_READ | ZX_VM_PERM_WRITE | ZX_VM_SPECIFIC_OVERWRITE, 391 addr - info.base, vmo, 0, size, &new_addr); 392 if (status == ZX_OK) 393 CHECK_EQ(new_addr, addr); 394 } 395 } 396 if (status == ZX_OK && addr != map_addr) 397 status = _zx_vmar_unmap(vmar_used, map_addr, addr - map_addr); 398 if (status == ZX_OK && end != map_end) 399 status = _zx_vmar_unmap(vmar_used, end, map_end - end); 400 } 401 _zx_handle_close(vmo); 402 403 if (status != ZX_OK) { 404 if (status != ZX_ERR_NO_MEMORY) 405 ReportMmapFailureAndDie(size, mem_type, "zx_vmar_map", status, false); 406 return nullptr; 407 } 408 409 IncreaseTotalMmap(size); 410 411 return reinterpret_cast<void *>(addr); 412 } 413 414 void UnmapOrDie(void *addr, uptr size, bool raw_report) { 415 UnmapOrDieVmar(addr, size, gSanitizerHeapVmar, raw_report); 416 } 417 418 void ReleaseMemoryPagesToOS(uptr beg, uptr end) { 419 uptr beg_aligned = RoundUpTo(beg, GetPageSize()); 420 uptr end_aligned = RoundDownTo(end, GetPageSize()); 421 if (beg_aligned < end_aligned) { 422 zx_handle_t root_vmar = _zx_vmar_root_self(); 423 CHECK_NE(root_vmar, ZX_HANDLE_INVALID); 424 zx_status_t status = 425 _zx_vmar_op_range(root_vmar, ZX_VMAR_OP_DECOMMIT, beg_aligned, 426 end_aligned - beg_aligned, nullptr, 0); 427 CHECK_EQ(status, ZX_OK); 428 } 429 } 430 431 void DumpProcessMap() { 432 // TODO(mcgrathr): write it 433 return; 434 } 435 436 bool IsAccessibleMemoryRange(uptr beg, uptr size) { 437 // TODO(mcgrathr): Figure out a better way. 438 zx_handle_t vmo; 439 zx_status_t status = _zx_vmo_create(size, 0, &vmo); 440 if (status == ZX_OK) { 441 status = _zx_vmo_write(vmo, reinterpret_cast<const void *>(beg), 0, size); 442 _zx_handle_close(vmo); 443 } 444 return status == ZX_OK; 445 } 446 447 bool TryMemCpy(void *dest, const void *src, uptr n) { 448 // TODO: implement. 449 return false; 450 } 451 452 // FIXME implement on this platform. 453 void GetMemoryProfile(fill_profile_f cb, uptr *stats) {} 454 455 bool ReadFileToBuffer(const char *file_name, char **buff, uptr *buff_size, 456 uptr *read_len, uptr max_len, error_t *errno_p) { 457 *errno_p = ZX_ERR_NOT_SUPPORTED; 458 return false; 459 } 460 461 void RawWrite(const char *buffer) { 462 constexpr size_t size = 128; 463 static _Thread_local char line[size]; 464 static _Thread_local size_t lastLineEnd = 0; 465 static _Thread_local size_t cur = 0; 466 467 while (*buffer) { 468 if (cur >= size) { 469 if (lastLineEnd == 0) 470 lastLineEnd = size; 471 __sanitizer_log_write(line, lastLineEnd); 472 internal_memmove(line, line + lastLineEnd, cur - lastLineEnd); 473 cur = cur - lastLineEnd; 474 lastLineEnd = 0; 475 } 476 if (*buffer == '\n') 477 lastLineEnd = cur + 1; 478 line[cur++] = *buffer++; 479 } 480 // Flush all complete lines before returning. 481 if (lastLineEnd != 0) { 482 __sanitizer_log_write(line, lastLineEnd); 483 internal_memmove(line, line + lastLineEnd, cur - lastLineEnd); 484 cur = cur - lastLineEnd; 485 lastLineEnd = 0; 486 } 487 } 488 489 void CatastrophicErrorWrite(const char *buffer, uptr length) { 490 __sanitizer_log_write(buffer, length); 491 } 492 493 char **StoredArgv; 494 char **StoredEnviron; 495 496 char **GetArgv() { return StoredArgv; } 497 char **GetEnviron() { return StoredEnviron; } 498 499 const char *GetEnv(const char *name) { 500 if (StoredEnviron) { 501 uptr NameLen = internal_strlen(name); 502 for (char **Env = StoredEnviron; *Env != 0; Env++) { 503 if (internal_strncmp(*Env, name, NameLen) == 0 && (*Env)[NameLen] == '=') 504 return (*Env) + NameLen + 1; 505 } 506 } 507 return nullptr; 508 } 509 510 uptr ReadBinaryName(/*out*/ char *buf, uptr buf_len) { 511 const char *argv0 = "<UNKNOWN>"; 512 if (StoredArgv && StoredArgv[0]) { 513 argv0 = StoredArgv[0]; 514 } 515 internal_strncpy(buf, argv0, buf_len); 516 return internal_strlen(buf); 517 } 518 519 uptr ReadLongProcessName(/*out*/ char *buf, uptr buf_len) { 520 return ReadBinaryName(buf, buf_len); 521 } 522 523 uptr MainThreadStackBase, MainThreadStackSize; 524 525 bool GetRandom(void *buffer, uptr length, bool blocking) { 526 _zx_cprng_draw(buffer, length); 527 return true; 528 } 529 530 u32 GetNumberOfCPUs() { return zx_system_get_num_cpus(); } 531 532 uptr GetRSS() { UNIMPLEMENTED(); } 533 534 void *internal_start_thread(void *(*func)(void *arg), void *arg) { return 0; } 535 void internal_join_thread(void *th) {} 536 537 void InitializePlatformCommonFlags(CommonFlags *cf) {} 538 539 } // namespace __sanitizer 540 541 using namespace __sanitizer; 542 543 extern "C" { 544 void __sanitizer_startup_hook(int argc, char **argv, char **envp, 545 void *stack_base, size_t stack_size) { 546 __sanitizer::StoredArgv = argv; 547 __sanitizer::StoredEnviron = envp; 548 __sanitizer::MainThreadStackBase = reinterpret_cast<uintptr_t>(stack_base); 549 __sanitizer::MainThreadStackSize = stack_size; 550 } 551 552 void __sanitizer_set_report_path(const char *path) { 553 // Handle the initialization code in each sanitizer, but no other calls. 554 // This setting is never consulted on Fuchsia. 555 DCHECK_EQ(path, common_flags()->log_path); 556 } 557 558 void __sanitizer_set_report_fd(void *fd) { 559 UNREACHABLE("not available on Fuchsia"); 560 } 561 562 const char *__sanitizer_get_report_path() { 563 UNREACHABLE("not available on Fuchsia"); 564 } 565 } // extern "C" 566 567 #endif // SANITIZER_FUCHSIA 568