libsanitizer/sanitizer_common/sanitizer_win.cpp

   1 //===-- sanitizer_win.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 ThreadSanitizer
  10 // run-time libraries and implements windows-specific functions from
  11 // sanitizer_libc.h.
  12 //===----------------------------------------------------------------------===//
  13
  14 #include "sanitizer_platform.h"
  15 #if SANITIZER_WINDOWS
  16
  17 #define WIN32_LEAN_AND_MEAN
  18 #define NOGDI
  19 #include <direct.h>
  20 #include <windows.h>
  21 #include <io.h>
  22 #include <psapi.h>
  23 #include <stdlib.h>
  24
  25 #include "sanitizer_common.h"
  26 #include "sanitizer_file.h"
  27 #include "sanitizer_libc.h"
  28 #include "sanitizer_mutex.h"
  29 #include "sanitizer_placement_new.h"
  30 #include "sanitizer_win_defs.h"
  31
  32 #if defined(PSAPI_VERSION) && PSAPI_VERSION == 1
  33 #pragma comment(lib, "psapi")
  34 #endif
  35 #if SANITIZER_WIN_TRACE
  36 #include <traceloggingprovider.h>
  37 //  Windows trace logging provider init
  38 #pragma comment(lib, "advapi32.lib")
  39 TRACELOGGING_DECLARE_PROVIDER(g_asan_provider);
  40 // GUID must be the same in utils/AddressSanitizerLoggingProvider.wprp
  41 TRACELOGGING_DEFINE_PROVIDER(g_asan_provider, "AddressSanitizerLoggingProvider",
  42                              (0x6c6c766d, 0x3846, 0x4e6a, 0xa4, 0xfb, 0x5b,
  43                               0x53, 0x0b, 0xd0, 0xf3, 0xfa));
  44 #else
  45 #define TraceLoggingUnregister(x)
  46 #endif
  47
  48 // For WaitOnAddress
  49 #  pragma comment(lib, "synchronization.lib")
  50
  51 // A macro to tell the compiler that this part of the code cannot be reached,
  52 // if the compiler supports this feature. Since we're using this in
  53 // code that is called when terminating the process, the expansion of the
  54 // macro should not terminate the process to avoid infinite recursion.
  55 #if defined(__clang__)
  56 # define BUILTIN_UNREACHABLE() __builtin_unreachable()
  57 #elif defined(__GNUC__) && \
  58     (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 5))
  59 # define BUILTIN_UNREACHABLE() __builtin_unreachable()
  60 #elif defined(_MSC_VER)
  61 # define BUILTIN_UNREACHABLE() __assume(0)
  62 #else
  63 # define BUILTIN_UNREACHABLE()
  64 #endif
  65
  66 namespace __sanitizer {
  67
  68 #include "sanitizer_syscall_generic.inc"
  69
  70 // --------------------- sanitizer_common.h
  71 uptr GetPageSize() {
  72   SYSTEM_INFO si;
  73   GetSystemInfo(&si);
  74   return si.dwPageSize;
  75 }
  76
  77 uptr GetMmapGranularity() {
  78   SYSTEM_INFO si;
  79   GetSystemInfo(&si);
  80   return si.dwAllocationGranularity;
  81 }
  82
  83 uptr GetMaxUserVirtualAddress() {
  84   SYSTEM_INFO si;
  85   GetSystemInfo(&si);
  86   return (uptr)si.lpMaximumApplicationAddress;
  87 }
  88
  89 uptr GetMaxVirtualAddress() {
  90   return GetMaxUserVirtualAddress();
  91 }
  92
  93 bool FileExists(const char *filename) {
  94   return ::GetFileAttributesA(filename) != INVALID_FILE_ATTRIBUTES;
  95 }
  96
  97 uptr internal_getpid() {
  98   return GetProcessId(GetCurrentProcess());
  99 }
 100
 101 int internal_dlinfo(void *handle, int request, void *p) {
 102   UNIMPLEMENTED();
 103 }
 104
 105 // In contrast to POSIX, on Windows GetCurrentThreadId()
 106 // returns a system-unique identifier.
 107 tid_t GetTid() {
 108   return GetCurrentThreadId();
 109 }
 110
 111 uptr GetThreadSelf() {
 112   return GetTid();
 113 }
 114
 115 #if !SANITIZER_GO
 116 void GetThreadStackTopAndBottom(bool at_initialization, uptr *stack_top,
 117                                 uptr *stack_bottom) {
 118   CHECK(stack_top);
 119   CHECK(stack_bottom);
 120   MEMORY_BASIC_INFORMATION mbi;
 121   CHECK_NE(VirtualQuery(&mbi /* on stack */, &mbi, sizeof(mbi)), 0);
 122   // FIXME: is it possible for the stack to not be a single allocation?
 123   // Are these values what ASan expects to get (reserved, not committed;
 124   // including stack guard page) ?
 125   *stack_top = (uptr)mbi.BaseAddress + mbi.RegionSize;
 126   *stack_bottom = (uptr)mbi.AllocationBase;
 127 }
 128 #endif  // #if !SANITIZER_GO
 129
 130 void *MmapOrDie(uptr size, const char *mem_type, bool raw_report) {
 131   void *rv = VirtualAlloc(0, size, MEM_RESERVE | MEM_COMMIT, PAGE_READWRITE);
 132   if (rv == 0)
 133     ReportMmapFailureAndDie(size, mem_type, "allocate",
 134                             GetLastError(), raw_report);
 135   return rv;
 136 }
 137
 138 void UnmapOrDie(void *addr, uptr size) {
 139   if (!size || !addr)
 140     return;
 141
 142   MEMORY_BASIC_INFORMATION mbi;
 143   CHECK(VirtualQuery(addr, &mbi, sizeof(mbi)));
 144
 145   // MEM_RELEASE can only be used to unmap whole regions previously mapped with
 146   // VirtualAlloc. So we first try MEM_RELEASE since it is better, and if that
 147   // fails try MEM_DECOMMIT.
 148   if (VirtualFree(addr, 0, MEM_RELEASE) == 0) {
 149     if (VirtualFree(addr, size, MEM_DECOMMIT) == 0) {
 150       Report("ERROR: %s failed to "
 151              "deallocate 0x%zx (%zd) bytes at address %p (error code: %d)\n",
 152              SanitizerToolName, size, size, addr, GetLastError());
 153       CHECK("unable to unmap" && 0);
 154     }
 155   }
 156 }
 157
 158 static void *ReturnNullptrOnOOMOrDie(uptr size, const char *mem_type,
 159                                      const char *mmap_type) {
 160   error_t last_error = GetLastError();
 161   if (last_error == ERROR_NOT_ENOUGH_MEMORY)
 162     return nullptr;
 163   ReportMmapFailureAndDie(size, mem_type, mmap_type, last_error);
 164 }
 165
 166 void *MmapOrDieOnFatalError(uptr size, const char *mem_type) {
 167   void *rv = VirtualAlloc(0, size, MEM_RESERVE | MEM_COMMIT, PAGE_READWRITE);
 168   if (rv == 0)
 169     return ReturnNullptrOnOOMOrDie(size, mem_type, "allocate");
 170   return rv;
 171 }
 172
 173 // We want to map a chunk of address space aligned to 'alignment'.
 174 void *MmapAlignedOrDieOnFatalError(uptr size, uptr alignment,
 175                                    const char *mem_type) {
 176   CHECK(IsPowerOfTwo(size));
 177   CHECK(IsPowerOfTwo(alignment));
 178
 179   // Windows will align our allocations to at least 64K.
 180   alignment = Max(alignment, GetMmapGranularity());
 181
 182   uptr mapped_addr =
 183       (uptr)VirtualAlloc(0, size, MEM_RESERVE | MEM_COMMIT, PAGE_READWRITE);
 184   if (!mapped_addr)
 185     return ReturnNullptrOnOOMOrDie(size, mem_type, "allocate aligned");
 186
 187   // If we got it right on the first try, return. Otherwise, unmap it and go to
 188   // the slow path.
 189   if (IsAligned(mapped_addr, alignment))
 190     return (void*)mapped_addr;
 191   if (VirtualFree((void *)mapped_addr, 0, MEM_RELEASE) == 0)
 192     ReportMmapFailureAndDie(size, mem_type, "deallocate", GetLastError());
 193
 194   // If we didn't get an aligned address, overallocate, find an aligned address,
 195   // unmap, and try to allocate at that aligned address.
 196   int retries = 0;
 197   const int kMaxRetries = 10;
 198   for (; retries < kMaxRetries &&
 199          (mapped_addr == 0 || !IsAligned(mapped_addr, alignment));
 200        retries++) {
 201     // Overallocate size + alignment bytes.
 202     mapped_addr =
 203         (uptr)VirtualAlloc(0, size + alignment, MEM_RESERVE, PAGE_NOACCESS);
 204     if (!mapped_addr)
 205       return ReturnNullptrOnOOMOrDie(size, mem_type, "allocate aligned");
 206
 207     // Find the aligned address.
 208     uptr aligned_addr = RoundUpTo(mapped_addr, alignment);
 209
 210     // Free the overallocation.
 211     if (VirtualFree((void *)mapped_addr, 0, MEM_RELEASE) == 0)
 212       ReportMmapFailureAndDie(size, mem_type, "deallocate", GetLastError());
 213
 214     // Attempt to allocate exactly the number of bytes we need at the aligned
 215     // address. This may fail for a number of reasons, in which case we continue
 216     // the loop.
 217     mapped_addr = (uptr)VirtualAlloc((void *)aligned_addr, size,
 218                                      MEM_RESERVE | MEM_COMMIT, PAGE_READWRITE);
 219   }
 220
 221   // Fail if we can't make this work quickly.
 222   if (retries == kMaxRetries && mapped_addr == 0)
 223     return ReturnNullptrOnOOMOrDie(size, mem_type, "allocate aligned");
 224
 225   return (void *)mapped_addr;
 226 }
 227
 228 bool MmapFixedNoReserve(uptr fixed_addr, uptr size, const char *name) {
 229   // FIXME: is this really "NoReserve"? On Win32 this does not matter much,
 230   // but on Win64 it does.
 231   (void)name;  // unsupported
 232 #if !SANITIZER_GO && SANITIZER_WINDOWS64
 233   // On asan/Windows64, use MEM_COMMIT would result in error
 234   // 1455:ERROR_COMMITMENT_LIMIT.
 235   // Asan uses exception handler to commit page on demand.
 236   void *p = VirtualAlloc((LPVOID)fixed_addr, size, MEM_RESERVE, PAGE_READWRITE);
 237 #else
 238   void *p = VirtualAlloc((LPVOID)fixed_addr, size, MEM_RESERVE | MEM_COMMIT,
 239                          PAGE_READWRITE);
 240 #endif
 241   if (p == 0) {
 242     Report("ERROR: %s failed to "
 243            "allocate %p (%zd) bytes at %p (error code: %d)\n",
 244            SanitizerToolName, size, size, fixed_addr, GetLastError());
 245     return false;
 246   }
 247   return true;
 248 }
 249
 250 bool MmapFixedSuperNoReserve(uptr fixed_addr, uptr size, const char *name) {
 251   // FIXME: Windows support large pages too. Might be worth checking
 252   return MmapFixedNoReserve(fixed_addr, size, name);
 253 }
 254
 255 // Memory space mapped by 'MmapFixedOrDie' must have been reserved by
 256 // 'MmapFixedNoAccess'.
 257 void *MmapFixedOrDie(uptr fixed_addr, uptr size, const char *name) {
 258   void *p = VirtualAlloc((LPVOID)fixed_addr, size,
 259       MEM_COMMIT, PAGE_READWRITE);
 260   if (p == 0) {
 261     char mem_type[30];
 262     internal_snprintf(mem_type, sizeof(mem_type), "memory at address 0x%zx",
 263                       fixed_addr);
 264     ReportMmapFailureAndDie(size, mem_type, "allocate", GetLastError());
 265   }
 266   return p;
 267 }
 268
 269 // Uses fixed_addr for now.
 270 // Will use offset instead once we've implemented this function for real.
 271 uptr ReservedAddressRange::Map(uptr fixed_addr, uptr size, const char *name) {
 272   return reinterpret_cast<uptr>(MmapFixedOrDieOnFatalError(fixed_addr, size));
 273 }
 274
 275 uptr ReservedAddressRange::MapOrDie(uptr fixed_addr, uptr size,
 276                                     const char *name) {
 277   return reinterpret_cast<uptr>(MmapFixedOrDie(fixed_addr, size));
 278 }
 279
 280 void ReservedAddressRange::Unmap(uptr addr, uptr size) {
 281   // Only unmap if it covers the entire range.
 282   CHECK((addr == reinterpret_cast<uptr>(base_)) && (size == size_));
 283   // We unmap the whole range, just null out the base.
 284   base_ = nullptr;
 285   size_ = 0;
 286   UnmapOrDie(reinterpret_cast<void*>(addr), size);
 287 }
 288
 289 void *MmapFixedOrDieOnFatalError(uptr fixed_addr, uptr size, const char *name) {
 290   void *p = VirtualAlloc((LPVOID)fixed_addr, size,
 291       MEM_COMMIT, PAGE_READWRITE);
 292   if (p == 0) {
 293     char mem_type[30];
 294     internal_snprintf(mem_type, sizeof(mem_type), "memory at address 0x%zx",
 295                       fixed_addr);
 296     return ReturnNullptrOnOOMOrDie(size, mem_type, "allocate");
 297   }
 298   return p;
 299 }
 300
 301 void *MmapNoReserveOrDie(uptr size, const char *mem_type) {
 302   // FIXME: make this really NoReserve?
 303   return MmapOrDie(size, mem_type);
 304 }
 305
 306 uptr ReservedAddressRange::Init(uptr size, const char *name, uptr fixed_addr) {
 307   base_ = fixed_addr ? MmapFixedNoAccess(fixed_addr, size) : MmapNoAccess(size);
 308   size_ = size;
 309   name_ = name;
 310   (void)os_handle_;  // unsupported
 311   return reinterpret_cast<uptr>(base_);
 312 }
 313
 314
 315 void *MmapFixedNoAccess(uptr fixed_addr, uptr size, const char *name) {
 316   (void)name; // unsupported
 317   void *res = VirtualAlloc((LPVOID)fixed_addr, size,
 318                            MEM_RESERVE, PAGE_NOACCESS);
 319   if (res == 0)
 320     Report("WARNING: %s failed to "
 321            "mprotect %p (%zd) bytes at %p (error code: %d)\n",
 322            SanitizerToolName, size, size, fixed_addr, GetLastError());
 323   return res;
 324 }
 325
 326 void *MmapNoAccess(uptr size) {
 327   void *res = VirtualAlloc(nullptr, size, MEM_RESERVE, PAGE_NOACCESS);
 328   if (res == 0)
 329     Report("WARNING: %s failed to "
 330            "mprotect %p (%zd) bytes (error code: %d)\n",
 331            SanitizerToolName, size, size, GetLastError());
 332   return res;
 333 }
 334
 335 bool MprotectNoAccess(uptr addr, uptr size) {
 336   DWORD old_protection;
 337   return VirtualProtect((LPVOID)addr, size, PAGE_NOACCESS, &old_protection);
 338 }
 339
 340 void ReleaseMemoryPagesToOS(uptr beg, uptr end) {
 341   uptr beg_aligned = RoundDownTo(beg, GetPageSizeCached()),
 342        end_aligned = RoundDownTo(end, GetPageSizeCached());
 343   CHECK(beg < end);                // make sure the region is sane
 344   if (beg_aligned == end_aligned)  // make sure we're freeing at least 1 page;
 345     return;
 346   UnmapOrDie((void *)beg, end_aligned - beg_aligned);
 347 }
 348
 349 void SetShadowRegionHugePageMode(uptr addr, uptr size) {
 350   // FIXME: probably similar to ReleaseMemoryToOS.
 351 }
 352
 353 bool DontDumpShadowMemory(uptr addr, uptr length) {
 354   // This is almost useless on 32-bits.
 355   // FIXME: add madvise-analog when we move to 64-bits.
 356   return true;
 357 }
 358
 359 uptr MapDynamicShadow(uptr shadow_size_bytes, uptr shadow_scale,
 360                       uptr min_shadow_base_alignment,
 361                       UNUSED uptr &high_mem_end) {
 362   const uptr granularity = GetMmapGranularity();
 363   const uptr alignment =
 364       Max<uptr>(granularity << shadow_scale, 1ULL << min_shadow_base_alignment);
 365   const uptr left_padding =
 366       Max<uptr>(granularity, 1ULL << min_shadow_base_alignment);
 367   uptr space_size = shadow_size_bytes + left_padding;
 368   uptr shadow_start = FindAvailableMemoryRange(space_size, alignment,
 369                                                granularity, nullptr, nullptr);
 370   CHECK_NE((uptr)0, shadow_start);
 371   CHECK(IsAligned(shadow_start, alignment));
 372   return shadow_start;
 373 }
 374
 375 uptr FindAvailableMemoryRange(uptr size, uptr alignment, uptr left_padding,
 376                               uptr *largest_gap_found,
 377                               uptr *max_occupied_addr) {
 378   uptr address = 0;
 379   while (true) {
 380     MEMORY_BASIC_INFORMATION info;
 381     if (!::VirtualQuery((void*)address, &info, sizeof(info)))
 382       return 0;
 383
 384     if (info.State == MEM_FREE) {
 385       uptr shadow_address = RoundUpTo((uptr)info.BaseAddress + left_padding,
 386                                       alignment);
 387       if (shadow_address + size < (uptr)info.BaseAddress + info.RegionSize)
 388         return shadow_address;
 389     }
 390
 391     // Move to the next region.
 392     address = (uptr)info.BaseAddress + info.RegionSize;
 393   }
 394   return 0;
 395 }
 396
 397 uptr MapDynamicShadowAndAliases(uptr shadow_size, uptr alias_size,
 398                                 uptr num_aliases, uptr ring_buffer_size) {
 399   CHECK(false && "HWASan aliasing is unimplemented on Windows");
 400   return 0;
 401 }
 402
 403 bool MemoryRangeIsAvailable(uptr range_start, uptr range_end) {
 404   MEMORY_BASIC_INFORMATION mbi;
 405   CHECK(VirtualQuery((void *)range_start, &mbi, sizeof(mbi)));
 406   return mbi.Protect == PAGE_NOACCESS &&
 407          (uptr)mbi.BaseAddress + mbi.RegionSize >= range_end;
 408 }
 409
 410 void *MapFileToMemory(const char *file_name, uptr *buff_size) {
 411   UNIMPLEMENTED();
 412 }
 413
 414 void *MapWritableFileToMemory(void *addr, uptr size, fd_t fd, OFF_T offset) {
 415   UNIMPLEMENTED();
 416 }
 417
 418 static const int kMaxEnvNameLength = 128;
 419 static const DWORD kMaxEnvValueLength = 32767;
 420
 421 namespace {
 422
 423 struct EnvVariable {
 424   char name[kMaxEnvNameLength];
 425   char value[kMaxEnvValueLength];
 426 };
 427
 428 }  // namespace
 429
 430 static const int kEnvVariables = 5;
 431 static EnvVariable env_vars[kEnvVariables];
 432 static int num_env_vars;
 433
 434 const char *GetEnv(const char *name) {
 435   // Note: this implementation caches the values of the environment variables
 436   // and limits their quantity.
 437   for (int i = 0; i < num_env_vars; i++) {
 438     if (0 == internal_strcmp(name, env_vars[i].name))
 439       return env_vars[i].value;
 440   }
 441   CHECK_LT(num_env_vars, kEnvVariables);
 442   DWORD rv = GetEnvironmentVariableA(name, env_vars[num_env_vars].value,
 443                                      kMaxEnvValueLength);
 444   if (rv > 0 && rv < kMaxEnvValueLength) {
 445     CHECK_LT(internal_strlen(name), kMaxEnvNameLength);
 446     internal_strncpy(env_vars[num_env_vars].name, name, kMaxEnvNameLength);
 447     num_env_vars++;
 448     return env_vars[num_env_vars - 1].value;
 449   }
 450   return 0;
 451 }
 452
 453 const char *GetPwd() {
 454   UNIMPLEMENTED();
 455 }
 456
 457 u32 GetUid() {
 458   UNIMPLEMENTED();
 459 }
 460
 461 namespace {
 462 struct ModuleInfo {
 463   const char *filepath;
 464   uptr base_address;
 465   uptr end_address;
 466 };
 467
 468 #if !SANITIZER_GO
 469 int CompareModulesBase(const void *pl, const void *pr) {
 470   const ModuleInfo *l = (const ModuleInfo *)pl, *r = (const ModuleInfo *)pr;
 471   if (l->base_address < r->base_address)
 472     return -1;
 473   return l->base_address > r->base_address;
 474 }
 475 #endif
 476 }  // namespace
 477
 478 #if !SANITIZER_GO
 479 void DumpProcessMap() {
 480   Report("Dumping process modules:\n");
 481   ListOfModules modules;
 482   modules.init();
 483   uptr num_modules = modules.size();
 484
 485   InternalMmapVector<ModuleInfo> module_infos(num_modules);
 486   for (size_t i = 0; i < num_modules; ++i) {
 487     module_infos[i].filepath = modules[i].full_name();
 488     module_infos[i].base_address = modules[i].ranges().front()->beg;
 489     module_infos[i].end_address = modules[i].ranges().back()->end;
 490   }
 491   qsort(module_infos.data(), num_modules, sizeof(ModuleInfo),
 492         CompareModulesBase);
 493
 494   for (size_t i = 0; i < num_modules; ++i) {
 495     const ModuleInfo &mi = module_infos[i];
 496     if (mi.end_address != 0) {
 497       Printf("\t%p-%p %s\n", mi.base_address, mi.end_address,
 498              mi.filepath[0] ? mi.filepath : "[no name]");
 499     } else if (mi.filepath[0]) {
 500       Printf("\t??\?-??? %s\n", mi.filepath);
 501     } else {
 502       Printf("\t???\n");
 503     }
 504   }
 505 }
 506 #endif
 507
 508 void DisableCoreDumperIfNecessary() {
 509   // Do nothing.
 510 }
 511
 512 void ReExec() {
 513   UNIMPLEMENTED();
 514 }
 515
 516 void PlatformPrepareForSandboxing(__sanitizer_sandbox_arguments *args) {}
 517
 518 bool StackSizeIsUnlimited() {
 519   UNIMPLEMENTED();
 520 }
 521
 522 void SetStackSizeLimitInBytes(uptr limit) {
 523   UNIMPLEMENTED();
 524 }
 525
 526 bool AddressSpaceIsUnlimited() {
 527   UNIMPLEMENTED();
 528 }
 529
 530 void SetAddressSpaceUnlimited() {
 531   UNIMPLEMENTED();
 532 }
 533
 534 bool IsPathSeparator(const char c) {
 535   return c == '\\' || c == '/';
 536 }
 537
 538 static bool IsAlpha(char c) {
 539   c = ToLower(c);
 540   return c >= 'a' && c <= 'z';
 541 }
 542
 543 bool IsAbsolutePath(const char *path) {
 544   return path != nullptr && IsAlpha(path[0]) && path[1] == ':' &&
 545          IsPathSeparator(path[2]);
 546 }
 547
 548 void internal_usleep(u64 useconds) { Sleep(useconds / 1000); }
 549
 550 u64 NanoTime() {
 551   static LARGE_INTEGER frequency = {};
 552   LARGE_INTEGER counter;
 553   if (UNLIKELY(frequency.QuadPart == 0)) {
 554     QueryPerformanceFrequency(&frequency);
 555     CHECK_NE(frequency.QuadPart, 0);
 556   }
 557   QueryPerformanceCounter(&counter);
 558   counter.QuadPart *= 1000ULL * 1000000ULL;
 559   counter.QuadPart /= frequency.QuadPart;
 560   return counter.QuadPart;
 561 }
 562
 563 u64 MonotonicNanoTime() { return NanoTime(); }
 564
 565 void Abort() {
 566   internal__exit(3);
 567 }
 568
 569 bool CreateDir(const char *pathname) { return _mkdir(pathname) == 0; }
 570
 571 #if !SANITIZER_GO
 572 // Read the file to extract the ImageBase field from the PE header. If ASLR is
 573 // disabled and this virtual address is available, the loader will typically
 574 // load the image at this address. Therefore, we call it the preferred base. Any
 575 // addresses in the DWARF typically assume that the object has been loaded at
 576 // this address.
 577 static uptr GetPreferredBase(const char *modname, char *buf, size_t buf_size) {
 578   fd_t fd = OpenFile(modname, RdOnly, nullptr);
 579   if (fd == kInvalidFd)
 580     return 0;
 581   FileCloser closer(fd);
 582
 583   // Read just the DOS header.
 584   IMAGE_DOS_HEADER dos_header;
 585   uptr bytes_read;
 586   if (!ReadFromFile(fd, &dos_header, sizeof(dos_header), &bytes_read) ||
 587       bytes_read != sizeof(dos_header))
 588     return 0;
 589
 590   // The file should start with the right signature.
 591   if (dos_header.e_magic != IMAGE_DOS_SIGNATURE)
 592     return 0;
 593
 594   // The layout at e_lfanew is:
 595   // "PE\0\0"
 596   // IMAGE_FILE_HEADER
 597   // IMAGE_OPTIONAL_HEADER
 598   // Seek to e_lfanew and read all that data.
 599   if (::SetFilePointer(fd, dos_header.e_lfanew, nullptr, FILE_BEGIN) ==
 600       INVALID_SET_FILE_POINTER)
 601     return 0;
 602   if (!ReadFromFile(fd, buf, buf_size, &bytes_read) || bytes_read != buf_size)
 603     return 0;
 604
 605   // Check for "PE\0\0" before the PE header.
 606   char *pe_sig = &buf[0];
 607   if (internal_memcmp(pe_sig, "PE\0\0", 4) != 0)
 608     return 0;
 609
 610   // Skip over IMAGE_FILE_HEADER. We could do more validation here if we wanted.
 611   IMAGE_OPTIONAL_HEADER *pe_header =
 612       (IMAGE_OPTIONAL_HEADER *)(pe_sig + 4 + sizeof(IMAGE_FILE_HEADER));
 613
 614   // Check for more magic in the PE header.
 615   if (pe_header->Magic != IMAGE_NT_OPTIONAL_HDR_MAGIC)
 616     return 0;
 617
 618   // Finally, return the ImageBase.
 619   return (uptr)pe_header->ImageBase;
 620 }
 621
 622 void ListOfModules::init() {
 623   clearOrInit();
 624   HANDLE cur_process = GetCurrentProcess();
 625
 626   // Query the list of modules.  Start by assuming there are no more than 256
 627   // modules and retry if that's not sufficient.
 628   HMODULE *hmodules = 0;
 629   uptr modules_buffer_size = sizeof(HMODULE) * 256;
 630   DWORD bytes_required;
 631   while (!hmodules) {
 632     hmodules = (HMODULE *)MmapOrDie(modules_buffer_size, __FUNCTION__);
 633     CHECK(EnumProcessModules(cur_process, hmodules, modules_buffer_size,
 634                              &bytes_required));
 635     if (bytes_required > modules_buffer_size) {
 636       // Either there turned out to be more than 256 hmodules, or new hmodules
 637       // could have loaded since the last try.  Retry.
 638       UnmapOrDie(hmodules, modules_buffer_size);
 639       hmodules = 0;
 640       modules_buffer_size = bytes_required;
 641     }
 642   }
 643
 644   InternalMmapVector<char> buf(4 + sizeof(IMAGE_FILE_HEADER) +
 645                                sizeof(IMAGE_OPTIONAL_HEADER));
 646   InternalMmapVector<wchar_t> modname_utf16(kMaxPathLength);
 647   InternalMmapVector<char> module_name(kMaxPathLength);
 648   // |num_modules| is the number of modules actually present,
 649   size_t num_modules = bytes_required / sizeof(HMODULE);
 650   for (size_t i = 0; i < num_modules; ++i) {
 651     HMODULE handle = hmodules[i];
 652     MODULEINFO mi;
 653     if (!GetModuleInformation(cur_process, handle, &mi, sizeof(mi)))
 654       continue;
 655
 656     // Get the UTF-16 path and convert to UTF-8.
 657     int modname_utf16_len =
 658         GetModuleFileNameW(handle, &modname_utf16[0], kMaxPathLength);
 659     if (modname_utf16_len == 0)
 660       modname_utf16[0] = '\0';
 661     int module_name_len = ::WideCharToMultiByte(
 662         CP_UTF8, 0, &modname_utf16[0], modname_utf16_len + 1, &module_name[0],
 663         kMaxPathLength, NULL, NULL);
 664     module_name[module_name_len] = '\0';
 665
 666     uptr base_address = (uptr)mi.lpBaseOfDll;
 667     uptr end_address = (uptr)mi.lpBaseOfDll + mi.SizeOfImage;
 668
 669     // Adjust the base address of the module so that we get a VA instead of an
 670     // RVA when computing the module offset. This helps llvm-symbolizer find the
 671     // right DWARF CU. In the common case that the image is loaded at it's
 672     // preferred address, we will now print normal virtual addresses.
 673     uptr preferred_base =
 674         GetPreferredBase(&module_name[0], &buf[0], buf.size());
 675     uptr adjusted_base = base_address - preferred_base;
 676
 677     modules_.push_back(LoadedModule());
 678     LoadedModule &cur_module = modules_.back();
 679     cur_module.set(&module_name[0], adjusted_base);
 680     // We add the whole module as one single address range.
 681     cur_module.addAddressRange(base_address, end_address, /*executable*/ true,
 682                                /*writable*/ true);
 683   }
 684   UnmapOrDie(hmodules, modules_buffer_size);
 685 }
 686
 687 void ListOfModules::fallbackInit() { clear(); }
 688
 689 // We can't use atexit() directly at __asan_init time as the CRT is not fully
 690 // initialized at this point.  Place the functions into a vector and use
 691 // atexit() as soon as it is ready for use (i.e. after .CRT$XIC initializers).
 692 InternalMmapVectorNoCtor<void (*)(void)> atexit_functions;
 693
 694 int Atexit(void (*function)(void)) {
 695   atexit_functions.push_back(function);
 696   return 0;
 697 }
 698
 699 static int RunAtexit() {
 700   TraceLoggingUnregister(g_asan_provider);
 701   int ret = 0;
 702   for (uptr i = 0; i < atexit_functions.size(); ++i) {
 703     ret |= atexit(atexit_functions[i]);
 704   }
 705   return ret;
 706 }
 707
 708 #pragma section(".CRT$XID", long, read)
 709 __declspec(allocate(".CRT$XID")) int (*__run_atexit)() = RunAtexit;
 710 #endif
 711
 712 // ------------------ sanitizer_libc.h
 713 fd_t OpenFile(const char *filename, FileAccessMode mode, error_t *last_error) {
 714   // FIXME: Use the wide variants to handle Unicode filenames.
 715   fd_t res;
 716   if (mode == RdOnly) {
 717     res = CreateFileA(filename, GENERIC_READ,
 718                       FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE,
 719                       nullptr, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, nullptr);
 720   } else if (mode == WrOnly) {
 721     res = CreateFileA(filename, GENERIC_WRITE, 0, nullptr, CREATE_ALWAYS,
 722                       FILE_ATTRIBUTE_NORMAL, nullptr);
 723   } else {
 724     UNIMPLEMENTED();
 725   }
 726   CHECK(res != kStdoutFd || kStdoutFd == kInvalidFd);
 727   CHECK(res != kStderrFd || kStderrFd == kInvalidFd);
 728   if (res == kInvalidFd && last_error)
 729     *last_error = GetLastError();
 730   return res;
 731 }
 732
 733 void CloseFile(fd_t fd) {
 734   CloseHandle(fd);
 735 }
 736
 737 bool ReadFromFile(fd_t fd, void *buff, uptr buff_size, uptr *bytes_read,
 738                   error_t *error_p) {
 739   CHECK(fd != kInvalidFd);
 740
 741   // bytes_read can't be passed directly to ReadFile:
 742   // uptr is unsigned long long on 64-bit Windows.
 743   unsigned long num_read_long;
 744
 745   bool success = ::ReadFile(fd, buff, buff_size, &num_read_long, nullptr);
 746   if (!success && error_p)
 747     *error_p = GetLastError();
 748   if (bytes_read)
 749     *bytes_read = num_read_long;
 750   return success;
 751 }
 752
 753 bool SupportsColoredOutput(fd_t fd) {
 754   // FIXME: support colored output.
 755   return false;
 756 }
 757
 758 bool WriteToFile(fd_t fd, const void *buff, uptr buff_size, uptr *bytes_written,
 759                  error_t *error_p) {
 760   CHECK(fd != kInvalidFd);
 761
 762   // Handle null optional parameters.
 763   error_t dummy_error;
 764   error_p = error_p ? error_p : &dummy_error;
 765   uptr dummy_bytes_written;
 766   bytes_written = bytes_written ? bytes_written : &dummy_bytes_written;
 767
 768   // Initialize output parameters in case we fail.
 769   *error_p = 0;
 770   *bytes_written = 0;
 771
 772   // Map the conventional Unix fds 1 and 2 to Windows handles. They might be
 773   // closed, in which case this will fail.
 774   if (fd == kStdoutFd || fd == kStderrFd) {
 775     fd = GetStdHandle(fd == kStdoutFd ? STD_OUTPUT_HANDLE : STD_ERROR_HANDLE);
 776     if (fd == 0) {
 777       *error_p = ERROR_INVALID_HANDLE;
 778       return false;
 779     }
 780   }
 781
 782   DWORD bytes_written_32;
 783   if (!WriteFile(fd, buff, buff_size, &bytes_written_32, 0)) {
 784     *error_p = GetLastError();
 785     return false;
 786   } else {
 787     *bytes_written = bytes_written_32;
 788     return true;
 789   }
 790 }
 791
 792 uptr internal_sched_yield() {
 793   Sleep(0);
 794   return 0;
 795 }
 796
 797 void internal__exit(int exitcode) {
 798   TraceLoggingUnregister(g_asan_provider);
 799   // ExitProcess runs some finalizers, so use TerminateProcess to avoid that.
 800   // The debugger doesn't stop on TerminateProcess like it does on ExitProcess,
 801   // so add our own breakpoint here.
 802   if (::IsDebuggerPresent())
 803     __debugbreak();
 804   TerminateProcess(GetCurrentProcess(), exitcode);
 805   BUILTIN_UNREACHABLE();
 806 }
 807
 808 uptr internal_ftruncate(fd_t fd, uptr size) {
 809   UNIMPLEMENTED();
 810 }
 811
 812 uptr GetRSS() {
 813   PROCESS_MEMORY_COUNTERS counters;
 814   if (!GetProcessMemoryInfo(GetCurrentProcess(), &counters, sizeof(counters)))
 815     return 0;
 816   return counters.WorkingSetSize;
 817 }
 818
 819 void *internal_start_thread(void *(*func)(void *arg), void *arg) { return 0; }
 820 void internal_join_thread(void *th) { }
 821
 822 void FutexWait(atomic_uint32_t *p, u32 cmp) {
 823   WaitOnAddress(p, &cmp, sizeof(cmp), INFINITE);
 824 }
 825
 826 void FutexWake(atomic_uint32_t *p, u32 count) {
 827   if (count == 1)
 828     WakeByAddressSingle(p);
 829   else
 830     WakeByAddressAll(p);
 831 }
 832
 833 uptr GetTlsSize() {
 834   return 0;
 835 }
 836
 837 void InitTlsSize() {
 838 }
 839
 840 void GetThreadStackAndTls(bool main, uptr *stk_addr, uptr *stk_size,
 841                           uptr *tls_addr, uptr *tls_size) {
 842 #if SANITIZER_GO
 843   *stk_addr = 0;
 844   *stk_size = 0;
 845   *tls_addr = 0;
 846   *tls_size = 0;
 847 #else
 848   uptr stack_top, stack_bottom;
 849   GetThreadStackTopAndBottom(main, &stack_top, &stack_bottom);
 850   *stk_addr = stack_bottom;
 851   *stk_size = stack_top - stack_bottom;
 852   *tls_addr = 0;
 853   *tls_size = 0;
 854 #endif
 855 }
 856
 857 void ReportFile::Write(const char *buffer, uptr length) {
 858   SpinMutexLock l(mu);
 859   ReopenIfNecessary();
 860   if (!WriteToFile(fd, buffer, length)) {
 861     // stderr may be closed, but we may be able to print to the debugger
 862     // instead.  This is the case when launching a program from Visual Studio,
 863     // and the following routine should write to its console.
 864     OutputDebugStringA(buffer);
 865   }
 866 }
 867
 868 void SetAlternateSignalStack() {
 869   // FIXME: Decide what to do on Windows.
 870 }
 871
 872 void UnsetAlternateSignalStack() {
 873   // FIXME: Decide what to do on Windows.
 874 }
 875
 876 void InstallDeadlySignalHandlers(SignalHandlerType handler) {
 877   (void)handler;
 878   // FIXME: Decide what to do on Windows.
 879 }
 880
 881 HandleSignalMode GetHandleSignalMode(int signum) {
 882   // FIXME: Decide what to do on Windows.
 883   return kHandleSignalNo;
 884 }
 885
 886 // Check based on flags if we should handle this exception.
 887 bool IsHandledDeadlyException(DWORD exceptionCode) {
 888   switch (exceptionCode) {
 889     case EXCEPTION_ACCESS_VIOLATION:
 890     case EXCEPTION_ARRAY_BOUNDS_EXCEEDED:
 891     case EXCEPTION_STACK_OVERFLOW:
 892     case EXCEPTION_DATATYPE_MISALIGNMENT:
 893     case EXCEPTION_IN_PAGE_ERROR:
 894       return common_flags()->handle_segv;
 895     case EXCEPTION_ILLEGAL_INSTRUCTION:
 896     case EXCEPTION_PRIV_INSTRUCTION:
 897     case EXCEPTION_BREAKPOINT:
 898       return common_flags()->handle_sigill;
 899     case EXCEPTION_FLT_DENORMAL_OPERAND:
 900     case EXCEPTION_FLT_DIVIDE_BY_ZERO:
 901     case EXCEPTION_FLT_INEXACT_RESULT:
 902     case EXCEPTION_FLT_INVALID_OPERATION:
 903     case EXCEPTION_FLT_OVERFLOW:
 904     case EXCEPTION_FLT_STACK_CHECK:
 905     case EXCEPTION_FLT_UNDERFLOW:
 906     case EXCEPTION_INT_DIVIDE_BY_ZERO:
 907     case EXCEPTION_INT_OVERFLOW:
 908       return common_flags()->handle_sigfpe;
 909   }
 910   return false;
 911 }
 912
 913 bool IsAccessibleMemoryRange(uptr beg, uptr size) {
 914   SYSTEM_INFO si;
 915   GetNativeSystemInfo(&si);
 916   uptr page_size = si.dwPageSize;
 917   uptr page_mask = ~(page_size - 1);
 918
 919   for (uptr page = beg & page_mask, end = (beg + size - 1) & page_mask;
 920        page <= end;) {
 921     MEMORY_BASIC_INFORMATION info;
 922     if (VirtualQuery((LPCVOID)page, &info, sizeof(info)) != sizeof(info))
 923       return false;
 924
 925     if (info.Protect == 0 || info.Protect == PAGE_NOACCESS ||
 926         info.Protect == PAGE_EXECUTE)
 927       return false;
 928
 929     if (info.RegionSize == 0)
 930       return false;
 931
 932     page += info.RegionSize;
 933   }
 934
 935   return true;
 936 }
 937
 938 bool SignalContext::IsStackOverflow() const {
 939   return (DWORD)GetType() == EXCEPTION_STACK_OVERFLOW;
 940 }
 941
 942 void SignalContext::InitPcSpBp() {
 943   EXCEPTION_RECORD *exception_record = (EXCEPTION_RECORD *)siginfo;
 944   CONTEXT *context_record = (CONTEXT *)context;
 945
 946   pc = (uptr)exception_record->ExceptionAddress;
 947 #ifdef _WIN64
 948   bp = (uptr)context_record->Rbp;
 949   sp = (uptr)context_record->Rsp;
 950 #else
 951   bp = (uptr)context_record->Ebp;
 952   sp = (uptr)context_record->Esp;
 953 #endif
 954 }
 955
 956 uptr SignalContext::GetAddress() const {
 957   EXCEPTION_RECORD *exception_record = (EXCEPTION_RECORD *)siginfo;
 958   if (exception_record->ExceptionCode == EXCEPTION_ACCESS_VIOLATION)
 959     return exception_record->ExceptionInformation[1];
 960   return (uptr)exception_record->ExceptionAddress;
 961 }
 962
 963 bool SignalContext::IsMemoryAccess() const {
 964   return ((EXCEPTION_RECORD *)siginfo)->ExceptionCode ==
 965          EXCEPTION_ACCESS_VIOLATION;
 966 }
 967
 968 bool SignalContext::IsTrueFaultingAddress() const { return true; }
 969
 970 SignalContext::WriteFlag SignalContext::GetWriteFlag() const {
 971   EXCEPTION_RECORD *exception_record = (EXCEPTION_RECORD *)siginfo;
 972
 973   // The write flag is only available for access violation exceptions.
 974   if (exception_record->ExceptionCode != EXCEPTION_ACCESS_VIOLATION)
 975     return SignalContext::UNKNOWN;
 976
 977   // The contents of this array are documented at
 978   // https://docs.microsoft.com/en-us/windows/win32/api/winnt/ns-winnt-exception_record
 979   // The first element indicates read as 0, write as 1, or execute as 8.  The
 980   // second element is the faulting address.
 981   switch (exception_record->ExceptionInformation[0]) {
 982     case 0:
 983       return SignalContext::READ;
 984     case 1:
 985       return SignalContext::WRITE;
 986     case 8:
 987       return SignalContext::UNKNOWN;
 988   }
 989   return SignalContext::UNKNOWN;
 990 }
 991
 992 void SignalContext::DumpAllRegisters(void *context) {
 993   // FIXME: Implement this.
 994 }
 995
 996 int SignalContext::GetType() const {
 997   return static_cast<const EXCEPTION_RECORD *>(siginfo)->ExceptionCode;
 998 }
 999
1000 const char *SignalContext::Describe() const {
1001   unsigned code = GetType();
1002   // Get the string description of the exception if this is a known deadly
1003   // exception.
1004   switch (code) {
1005     case EXCEPTION_ACCESS_VIOLATION:
1006       return "access-violation";
1007     case EXCEPTION_ARRAY_BOUNDS_EXCEEDED:
1008       return "array-bounds-exceeded";
1009     case EXCEPTION_STACK_OVERFLOW:
1010       return "stack-overflow";
1011     case EXCEPTION_DATATYPE_MISALIGNMENT:
1012       return "datatype-misalignment";
1013     case EXCEPTION_IN_PAGE_ERROR:
1014       return "in-page-error";
1015     case EXCEPTION_ILLEGAL_INSTRUCTION:
1016       return "illegal-instruction";
1017     case EXCEPTION_PRIV_INSTRUCTION:
1018       return "priv-instruction";
1019     case EXCEPTION_BREAKPOINT:
1020       return "breakpoint";
1021     case EXCEPTION_FLT_DENORMAL_OPERAND:
1022       return "flt-denormal-operand";
1023     case EXCEPTION_FLT_DIVIDE_BY_ZERO:
1024       return "flt-divide-by-zero";
1025     case EXCEPTION_FLT_INEXACT_RESULT:
1026       return "flt-inexact-result";
1027     case EXCEPTION_FLT_INVALID_OPERATION:
1028       return "flt-invalid-operation";
1029     case EXCEPTION_FLT_OVERFLOW:
1030       return "flt-overflow";
1031     case EXCEPTION_FLT_STACK_CHECK:
1032       return "flt-stack-check";
1033     case EXCEPTION_FLT_UNDERFLOW:
1034       return "flt-underflow";
1035     case EXCEPTION_INT_DIVIDE_BY_ZERO:
1036       return "int-divide-by-zero";
1037     case EXCEPTION_INT_OVERFLOW:
1038       return "int-overflow";
1039   }
1040   return "unknown exception";
1041 }
1042
1043 uptr ReadBinaryName(/*out*/char *buf, uptr buf_len) {
1044   if (buf_len == 0)
1045     return 0;
1046
1047   // Get the UTF-16 path and convert to UTF-8.
1048   InternalMmapVector<wchar_t> binname_utf16(kMaxPathLength);
1049   int binname_utf16_len =
1050       GetModuleFileNameW(NULL, &binname_utf16[0], kMaxPathLength);
1051   if (binname_utf16_len == 0) {
1052     buf[0] = '\0';
1053     return 0;
1054   }
1055   int binary_name_len =
1056       ::WideCharToMultiByte(CP_UTF8, 0, &binname_utf16[0], binname_utf16_len,
1057                             buf, buf_len, NULL, NULL);
1058   if ((unsigned)binary_name_len == buf_len)
1059     --binary_name_len;
1060   buf[binary_name_len] = '\0';
1061   return binary_name_len;
1062 }
1063
1064 uptr ReadLongProcessName(/*out*/char *buf, uptr buf_len) {
1065   return ReadBinaryName(buf, buf_len);
1066 }
1067
1068 void CheckVMASize() {
1069   // Do nothing.
1070 }
1071
1072 void InitializePlatformEarly() {
1073   // Do nothing.
1074 }
1075
1076 void MaybeReexec() {
1077   // No need to re-exec on Windows.
1078 }
1079
1080 void CheckASLR() {
1081   // Do nothing
1082 }
1083
1084 void CheckMPROTECT() {
1085   // Do nothing
1086 }
1087
1088 char **GetArgv() {
1089   // FIXME: Actually implement this function.
1090   return 0;
1091 }
1092
1093 char **GetEnviron() {
1094   // FIXME: Actually implement this function.
1095   return 0;
1096 }
1097
1098 pid_t StartSubprocess(const char *program, const char *const argv[],
1099                       const char *const envp[], fd_t stdin_fd, fd_t stdout_fd,
1100                       fd_t stderr_fd) {
1101   // FIXME: implement on this platform
1102   // Should be implemented based on
1103   // SymbolizerProcess::StarAtSymbolizerSubprocess
1104   // from lib/sanitizer_common/sanitizer_symbolizer_win.cpp.
1105   return -1;
1106 }
1107
1108 bool IsProcessRunning(pid_t pid) {
1109   // FIXME: implement on this platform.
1110   return false;
1111 }
1112
1113 int WaitForProcess(pid_t pid) { return -1; }
1114
1115 // FIXME implement on this platform.
1116 void GetMemoryProfile(fill_profile_f cb, uptr *stats, uptr stats_size) { }
1117
1118 void CheckNoDeepBind(const char *filename, int flag) {
1119   // Do nothing.
1120 }
1121
1122 // FIXME: implement on this platform.
1123 bool GetRandom(void *buffer, uptr length, bool blocking) {
1124   UNIMPLEMENTED();
1125 }
1126
1127 u32 GetNumberOfCPUs() {
1128   SYSTEM_INFO sysinfo = {};
1129   GetNativeSystemInfo(&sysinfo);
1130   return sysinfo.dwNumberOfProcessors;
1131 }
1132
1133 #if SANITIZER_WIN_TRACE
1134 // TODO(mcgov): Rename this project-wide to PlatformLogInit
1135 void AndroidLogInit(void) {
1136   HRESULT hr = TraceLoggingRegister(g_asan_provider);
1137   if (!SUCCEEDED(hr))
1138     return;
1139 }
1140
1141 void SetAbortMessage(const char *) {}
1142
1143 void LogFullErrorReport(const char *buffer) {
1144   if (common_flags()->log_to_syslog) {
1145     InternalMmapVector<wchar_t> filename;
1146     DWORD filename_length = 0;
1147     do {
1148       filename.resize(filename.size() + 0x100);
1149       filename_length =
1150           GetModuleFileNameW(NULL, filename.begin(), filename.size());
1151     } while (filename_length >= filename.size());
1152     TraceLoggingWrite(g_asan_provider, "AsanReportEvent",
1153                       TraceLoggingValue(filename.begin(), "ExecutableName"),
1154                       TraceLoggingValue(buffer, "AsanReportContents"));
1155   }
1156 }
1157 #endif // SANITIZER_WIN_TRACE
1158
1159 void InitializePlatformCommonFlags(CommonFlags *cf) {}
1160
1161 }  // namespace __sanitizer
1162
1163 #endif  // _WIN32