libsanitizer/sanitizer_common/sanitizer_common.h

   1 //===-- sanitizer_common.h --------------------------------------*- C++ -*-===//
   2 //
   3 // This file is distributed under the University of Illinois Open Source
   4 // License. See LICENSE.TXT for details.
   5 //
   6 //===----------------------------------------------------------------------===//
   7 //
   8 // This file is shared between run-time libraries of sanitizers.
   9 //
  10 // It declares common functions and classes that are used in both runtimes.
  11 // Implementation of some functions are provided in sanitizer_common, while
  12 // others must be defined by run-time library itself.
  13 //===----------------------------------------------------------------------===//
  14 #ifndef SANITIZER_COMMON_H
  15 #define SANITIZER_COMMON_H
  16
  17 #include "sanitizer_flags.h"
  18 #include "sanitizer_interface_internal.h"
  19 #include "sanitizer_internal_defs.h"
  20 #include "sanitizer_libc.h"
  21 #include "sanitizer_list.h"
  22 #include "sanitizer_mutex.h"
  23
  24 #if defined(_MSC_VER) && !defined(__clang__)
  25 extern "C" void _ReadWriteBarrier();
  26 #pragma intrinsic(_ReadWriteBarrier)
  27 #endif
  28
  29 namespace __sanitizer {
  30
  31 struct AddressInfo;
  32 struct BufferedStackTrace;
  33 struct SignalContext;
  34 struct StackTrace;
  35
  36 // Constants.
  37 const uptr kWordSize = SANITIZER_WORDSIZE / 8;
  38 const uptr kWordSizeInBits = 8 * kWordSize;
  39
  40 const uptr kCacheLineSize = SANITIZER_CACHE_LINE_SIZE;
  41
  42 const uptr kMaxPathLength = 4096;
  43
  44 const uptr kMaxThreadStackSize = 1 << 30;  // 1Gb
  45
  46 static const uptr kErrorMessageBufferSize = 1 << 16;
  47
  48 // Denotes fake PC values that come from JIT/JAVA/etc.
  49 // For such PC values __tsan_symbolize_external_ex() will be called.
  50 const u64 kExternalPCBit = 1ULL << 60;
  51
  52 extern const char *SanitizerToolName;  // Can be changed by the tool.
  53
  54 extern atomic_uint32_t current_verbosity;
  55 INLINE void SetVerbosity(int verbosity) {
  56   atomic_store(&current_verbosity, verbosity, memory_order_relaxed);
  57 }
  58 INLINE int Verbosity() {
  59   return atomic_load(&current_verbosity, memory_order_relaxed);
  60 }
  61
  62 uptr GetPageSize();
  63 extern uptr PageSizeCached;
  64 INLINE uptr GetPageSizeCached() {
  65   if (!PageSizeCached)
  66     PageSizeCached = GetPageSize();
  67   return PageSizeCached;
  68 }
  69 uptr GetMmapGranularity();
  70 uptr GetMaxVirtualAddress();
  71 uptr GetMaxUserVirtualAddress();
  72 // Threads
  73 tid_t GetTid();
  74 int TgKill(pid_t pid, tid_t tid, int sig);
  75 uptr GetThreadSelf();
  76 void GetThreadStackTopAndBottom(bool at_initialization, uptr *stack_top,
  77                                 uptr *stack_bottom);
  78 void GetThreadStackAndTls(bool main, uptr *stk_addr, uptr *stk_size,
  79                           uptr *tls_addr, uptr *tls_size);
  80
  81 // Memory management
  82 void *MmapOrDie(uptr size, const char *mem_type, bool raw_report = false);
  83 INLINE void *MmapOrDieQuietly(uptr size, const char *mem_type) {
  84   return MmapOrDie(size, mem_type, /*raw_report*/ true);
  85 }
  86 void UnmapOrDie(void *addr, uptr size);
  87 // Behaves just like MmapOrDie, but tolerates out of memory condition, in that
  88 // case returns nullptr.
  89 void *MmapOrDieOnFatalError(uptr size, const char *mem_type);
  90 bool MmapFixedNoReserve(uptr fixed_addr, uptr size, const char *name = nullptr)
  91      WARN_UNUSED_RESULT;
  92 void *MmapNoReserveOrDie(uptr size, const char *mem_type);
  93 void *MmapFixedOrDie(uptr fixed_addr, uptr size);
  94 // Behaves just like MmapFixedOrDie, but tolerates out of memory condition, in
  95 // that case returns nullptr.
  96 void *MmapFixedOrDieOnFatalError(uptr fixed_addr, uptr size);
  97 void *MmapFixedNoAccess(uptr fixed_addr, uptr size, const char *name = nullptr);
  98 void *MmapNoAccess(uptr size);
  99 // Map aligned chunk of address space; size and alignment are powers of two.
 100 // Dies on all but out of memory errors, in the latter case returns nullptr.
 101 void *MmapAlignedOrDieOnFatalError(uptr size, uptr alignment,
 102                                    const char *mem_type);
 103 // Disallow access to a memory range.  Use MmapFixedNoAccess to allocate an
 104 // unaccessible memory.
 105 bool MprotectNoAccess(uptr addr, uptr size);
 106 bool MprotectReadOnly(uptr addr, uptr size);
 107
 108 void MprotectMallocZones(void *addr, int prot);
 109
 110 // Find an available address space.
 111 uptr FindAvailableMemoryRange(uptr size, uptr alignment, uptr left_padding,
 112                               uptr *largest_gap_found, uptr *max_occupied_addr);
 113
 114 // Used to check if we can map shadow memory to a fixed location.
 115 bool MemoryRangeIsAvailable(uptr range_start, uptr range_end);
 116 // Releases memory pages entirely within the [beg, end] address range. Noop if
 117 // the provided range does not contain at least one entire page.
 118 void ReleaseMemoryPagesToOS(uptr beg, uptr end);
 119 void IncreaseTotalMmap(uptr size);
 120 void DecreaseTotalMmap(uptr size);
 121 uptr GetRSS();
 122 bool NoHugePagesInRegion(uptr addr, uptr length);
 123 bool DontDumpShadowMemory(uptr addr, uptr length);
 124 // Check if the built VMA size matches the runtime one.
 125 void CheckVMASize();
 126 void RunMallocHooks(const void *ptr, uptr size);
 127 void RunFreeHooks(const void *ptr);
 128
 129 class ReservedAddressRange {
 130  public:
 131   uptr Init(uptr size, const char *name = nullptr, uptr fixed_addr = 0);
 132   uptr Map(uptr fixed_addr, uptr size);
 133   uptr MapOrDie(uptr fixed_addr, uptr size);
 134   void Unmap(uptr addr, uptr size);
 135   void *base() const { return base_; }
 136   uptr size() const { return size_; }
 137
 138  private:
 139   void* base_;
 140   uptr size_;
 141   const char* name_;
 142   uptr os_handle_;
 143 };
 144
 145 typedef void (*fill_profile_f)(uptr start, uptr rss, bool file,
 146                                /*out*/uptr *stats, uptr stats_size);
 147
 148 // Parse the contents of /proc/self/smaps and generate a memory profile.
 149 // |cb| is a tool-specific callback that fills the |stats| array containing
 150 // |stats_size| elements.
 151 void GetMemoryProfile(fill_profile_f cb, uptr *stats, uptr stats_size);
 152
 153 // Simple low-level (mmap-based) allocator for internal use. Doesn't have
 154 // constructor, so all instances of LowLevelAllocator should be
 155 // linker initialized.
 156 class LowLevelAllocator {
 157  public:
 158   // Requires an external lock.
 159   void *Allocate(uptr size);
 160  private:
 161   char *allocated_end_;
 162   char *allocated_current_;
 163 };
 164 // Set the min alignment of LowLevelAllocator to at least alignment.
 165 void SetLowLevelAllocateMinAlignment(uptr alignment);
 166 typedef void (*LowLevelAllocateCallback)(uptr ptr, uptr size);
 167 // Allows to register tool-specific callbacks for LowLevelAllocator.
 168 // Passing NULL removes the callback.
 169 void SetLowLevelAllocateCallback(LowLevelAllocateCallback callback);
 170
 171 // IO
 172 void CatastrophicErrorWrite(const char *buffer, uptr length);
 173 void RawWrite(const char *buffer);
 174 bool ColorizeReports();
 175 void RemoveANSIEscapeSequencesFromString(char *buffer);
 176 void Printf(const char *format, ...);
 177 void Report(const char *format, ...);
 178 void SetPrintfAndReportCallback(void (*callback)(const char *));
 179 #define VReport(level, ...)                                              \
 180   do {                                                                   \
 181     if ((uptr)Verbosity() >= (level)) Report(__VA_ARGS__); \
 182   } while (0)
 183 #define VPrintf(level, ...)                                              \
 184   do {                                                                   \
 185     if ((uptr)Verbosity() >= (level)) Printf(__VA_ARGS__); \
 186   } while (0)
 187
 188 // Lock sanitizer error reporting and protects against nested errors.
 189 class ScopedErrorReportLock {
 190  public:
 191   ScopedErrorReportLock();
 192   ~ScopedErrorReportLock();
 193
 194   static void CheckLocked();
 195 };
 196
 197 extern uptr stoptheworld_tracer_pid;
 198 extern uptr stoptheworld_tracer_ppid;
 199
 200 bool IsAccessibleMemoryRange(uptr beg, uptr size);
 201
 202 // Error report formatting.
 203 const char *StripPathPrefix(const char *filepath,
 204                             const char *strip_file_prefix);
 205 // Strip the directories from the module name.
 206 const char *StripModuleName(const char *module);
 207
 208 // OS
 209 uptr ReadBinaryName(/*out*/char *buf, uptr buf_len);
 210 uptr ReadBinaryNameCached(/*out*/char *buf, uptr buf_len);
 211 uptr ReadLongProcessName(/*out*/ char *buf, uptr buf_len);
 212 const char *GetProcessName();
 213 void UpdateProcessName();
 214 void CacheBinaryName();
 215 void DisableCoreDumperIfNecessary();
 216 void DumpProcessMap();
 217 void PrintModuleMap();
 218 const char *GetEnv(const char *name);
 219 bool SetEnv(const char *name, const char *value);
 220
 221 u32 GetUid();
 222 void ReExec();
 223 void CheckASLR();
 224 char **GetArgv();
 225 void PrintCmdline();
 226 bool StackSizeIsUnlimited();
 227 uptr GetStackSizeLimitInBytes();
 228 void SetStackSizeLimitInBytes(uptr limit);
 229 bool AddressSpaceIsUnlimited();
 230 void SetAddressSpaceUnlimited();
 231 void AdjustStackSize(void *attr);
 232 void PlatformPrepareForSandboxing(__sanitizer_sandbox_arguments *args);
 233 void SetSandboxingCallback(void (*f)());
 234
 235 void InitializeCoverage(bool enabled, const char *coverage_dir);
 236
 237 void InitTlsSize();
 238 uptr GetTlsSize();
 239
 240 // Other
 241 void SleepForSeconds(int seconds);
 242 void SleepForMillis(int millis);
 243 u64 NanoTime();
 244 u64 MonotonicNanoTime();
 245 int Atexit(void (*function)(void));
 246 bool TemplateMatch(const char *templ, const char *str);
 247
 248 // Exit
 249 void NORETURN Abort();
 250 void NORETURN Die();
 251 void NORETURN
 252 CheckFailed(const char *file, int line, const char *cond, u64 v1, u64 v2);
 253 void NORETURN ReportMmapFailureAndDie(uptr size, const char *mem_type,
 254                                       const char *mmap_type, error_t err,
 255                                       bool raw_report = false);
 256
 257 // Specific tools may override behavior of "Die" and "CheckFailed" functions
 258 // to do tool-specific job.
 259 typedef void (*DieCallbackType)(void);
 260
 261 // It's possible to add several callbacks that would be run when "Die" is
 262 // called. The callbacks will be run in the opposite order. The tools are
 263 // strongly recommended to setup all callbacks during initialization, when there
 264 // is only a single thread.
 265 bool AddDieCallback(DieCallbackType callback);
 266 bool RemoveDieCallback(DieCallbackType callback);
 267
 268 void SetUserDieCallback(DieCallbackType callback);
 269
 270 typedef void (*CheckFailedCallbackType)(const char *, int, const char *,
 271                                        u64, u64);
 272 void SetCheckFailedCallback(CheckFailedCallbackType callback);
 273
 274 // Callback will be called if soft_rss_limit_mb is given and the limit is
 275 // exceeded (exceeded==true) or if rss went down below the limit
 276 // (exceeded==false).
 277 // The callback should be registered once at the tool init time.
 278 void SetSoftRssLimitExceededCallback(void (*Callback)(bool exceeded));
 279
 280 // Functions related to signal handling.
 281 typedef void (*SignalHandlerType)(int, void *, void *);
 282 HandleSignalMode GetHandleSignalMode(int signum);
 283 void InstallDeadlySignalHandlers(SignalHandlerType handler);
 284
 285 // Signal reporting.
 286 // Each sanitizer uses slightly different implementation of stack unwinding.
 287 typedef void (*UnwindSignalStackCallbackType)(const SignalContext &sig,
 288                                               const void *callback_context,
 289                                               BufferedStackTrace *stack);
 290 // Print deadly signal report and die.
 291 void HandleDeadlySignal(void *siginfo, void *context, u32 tid,
 292                         UnwindSignalStackCallbackType unwind,
 293                         const void *unwind_context);
 294
 295 // Part of HandleDeadlySignal, exposed for asan.
 296 void StartReportDeadlySignal();
 297 // Part of HandleDeadlySignal, exposed for asan.
 298 void ReportDeadlySignal(const SignalContext &sig, u32 tid,
 299                         UnwindSignalStackCallbackType unwind,
 300                         const void *unwind_context);
 301
 302 // Alternative signal stack (POSIX-only).
 303 void SetAlternateSignalStack();
 304 void UnsetAlternateSignalStack();
 305
 306 // We don't want a summary too long.
 307 const int kMaxSummaryLength = 1024;
 308 // Construct a one-line string:
 309 //   SUMMARY: SanitizerToolName: error_message
 310 // and pass it to __sanitizer_report_error_summary.
 311 // If alt_tool_name is provided, it's used in place of SanitizerToolName.
 312 void ReportErrorSummary(const char *error_message,
 313                         const char *alt_tool_name = nullptr);
 314 // Same as above, but construct error_message as:
 315 //   error_type file:line[:column][ function]
 316 void ReportErrorSummary(const char *error_type, const AddressInfo &info,
 317                         const char *alt_tool_name = nullptr);
 318 // Same as above, but obtains AddressInfo by symbolizing top stack trace frame.
 319 void ReportErrorSummary(const char *error_type, const StackTrace *trace,
 320                         const char *alt_tool_name = nullptr);
 321
 322 void ReportMmapWriteExec(int prot);
 323
 324 // Math
 325 #if SANITIZER_WINDOWS && !defined(__clang__) && !defined(__GNUC__)
 326 extern "C" {
 327 unsigned char _BitScanForward(unsigned long *index, unsigned long mask);  // NOLINT
 328 unsigned char _BitScanReverse(unsigned long *index, unsigned long mask);  // NOLINT
 329 #if defined(_WIN64)
 330 unsigned char _BitScanForward64(unsigned long *index, unsigned __int64 mask);  // NOLINT
 331 unsigned char _BitScanReverse64(unsigned long *index, unsigned __int64 mask);  // NOLINT
 332 #endif
 333 }
 334 #endif
 335
 336 INLINE uptr MostSignificantSetBitIndex(uptr x) {
 337   CHECK_NE(x, 0U);
 338   unsigned long up;  // NOLINT
 339 #if !SANITIZER_WINDOWS || defined(__clang__) || defined(__GNUC__)
 340 # ifdef _WIN64
 341   up = SANITIZER_WORDSIZE - 1 - __builtin_clzll(x);
 342 # else
 343   up = SANITIZER_WORDSIZE - 1 - __builtin_clzl(x);
 344 # endif
 345 #elif defined(_WIN64)
 346   _BitScanReverse64(&up, x);
 347 #else
 348   _BitScanReverse(&up, x);
 349 #endif
 350   return up;
 351 }
 352
 353 INLINE uptr LeastSignificantSetBitIndex(uptr x) {
 354   CHECK_NE(x, 0U);
 355   unsigned long up;  // NOLINT
 356 #if !SANITIZER_WINDOWS || defined(__clang__) || defined(__GNUC__)
 357 # ifdef _WIN64
 358   up = __builtin_ctzll(x);
 359 # else
 360   up = __builtin_ctzl(x);
 361 # endif
 362 #elif defined(_WIN64)
 363   _BitScanForward64(&up, x);
 364 #else
 365   _BitScanForward(&up, x);
 366 #endif
 367   return up;
 368 }
 369
 370 INLINE bool IsPowerOfTwo(uptr x) {
 371   return (x & (x - 1)) == 0;
 372 }
 373
 374 INLINE uptr RoundUpToPowerOfTwo(uptr size) {
 375   CHECK(size);
 376   if (IsPowerOfTwo(size)) return size;
 377
 378   uptr up = MostSignificantSetBitIndex(size);
 379   CHECK_LT(size, (1ULL << (up + 1)));
 380   CHECK_GT(size, (1ULL << up));
 381   return 1ULL << (up + 1);
 382 }
 383
 384 INLINE uptr RoundUpTo(uptr size, uptr boundary) {
 385   RAW_CHECK(IsPowerOfTwo(boundary));
 386   return (size + boundary - 1) & ~(boundary - 1);
 387 }
 388
 389 INLINE uptr RoundDownTo(uptr x, uptr boundary) {
 390   return x & ~(boundary - 1);
 391 }
 392
 393 INLINE bool IsAligned(uptr a, uptr alignment) {
 394   return (a & (alignment - 1)) == 0;
 395 }
 396
 397 INLINE uptr Log2(uptr x) {
 398   CHECK(IsPowerOfTwo(x));
 399   return LeastSignificantSetBitIndex(x);
 400 }
 401
 402 // Don't use std::min, std::max or std::swap, to minimize dependency
 403 // on libstdc++.
 404 template<class T> T Min(T a, T b) { return a < b ? a : b; }
 405 template<class T> T Max(T a, T b) { return a > b ? a : b; }
 406 template<class T> void Swap(T& a, T& b) {
 407   T tmp = a;
 408   a = b;
 409   b = tmp;
 410 }
 411
 412 // Char handling
 413 INLINE bool IsSpace(int c) {
 414   return (c == ' ') || (c == '\n') || (c == '\t') ||
 415          (c == '\f') || (c == '\r') || (c == '\v');
 416 }
 417 INLINE bool IsDigit(int c) {
 418   return (c >= '0') && (c <= '9');
 419 }
 420 INLINE int ToLower(int c) {
 421   return (c >= 'A' && c <= 'Z') ? (c + 'a' - 'A') : c;
 422 }
 423
 424 // A low-level vector based on mmap. May incur a significant memory overhead for
 425 // small vectors.
 426 // WARNING: The current implementation supports only POD types.
 427 template<typename T>
 428 class InternalMmapVectorNoCtor {
 429  public:
 430   void Initialize(uptr initial_capacity) {
 431     capacity_bytes_ = 0;
 432     size_ = 0;
 433     data_ = 0;
 434     reserve(initial_capacity);
 435   }
 436   void Destroy() { UnmapOrDie(data_, capacity_bytes_); }
 437   T &operator[](uptr i) {
 438     CHECK_LT(i, size_);
 439     return data_[i];
 440   }
 441   const T &operator[](uptr i) const {
 442     CHECK_LT(i, size_);
 443     return data_[i];
 444   }
 445   void push_back(const T &element) {
 446     CHECK_LE(size_, capacity());
 447     if (size_ == capacity()) {
 448       uptr new_capacity = RoundUpToPowerOfTwo(size_ + 1);
 449       Realloc(new_capacity);
 450     }
 451     internal_memcpy(&data_[size_++], &element, sizeof(T));
 452   }
 453   T &back() {
 454     CHECK_GT(size_, 0);
 455     return data_[size_ - 1];
 456   }
 457   void pop_back() {
 458     CHECK_GT(size_, 0);
 459     size_--;
 460   }
 461   uptr size() const {
 462     return size_;
 463   }
 464   const T *data() const {
 465     return data_;
 466   }
 467   T *data() {
 468     return data_;
 469   }
 470   uptr capacity() const { return capacity_bytes_ / sizeof(T); }
 471   void reserve(uptr new_size) {
 472     // Never downsize internal buffer.
 473     if (new_size > capacity())
 474       Realloc(new_size);
 475   }
 476   void resize(uptr new_size) {
 477     if (new_size > size_) {
 478       reserve(new_size);
 479       internal_memset(&data_[size_], 0, sizeof(T) * (new_size - size_));
 480     }
 481     size_ = new_size;
 482   }
 483
 484   void clear() { size_ = 0; }
 485   bool empty() const { return size() == 0; }
 486
 487   const T *begin() const {
 488     return data();
 489   }
 490   T *begin() {
 491     return data();
 492   }
 493   const T *end() const {
 494     return data() + size();
 495   }
 496   T *end() {
 497     return data() + size();
 498   }
 499
 500   void swap(InternalMmapVectorNoCtor &other) {
 501     Swap(data_, other.data_);
 502     Swap(capacity_bytes_, other.capacity_bytes_);
 503     Swap(size_, other.size_);
 504   }
 505
 506  private:
 507   void Realloc(uptr new_capacity) {
 508     CHECK_GT(new_capacity, 0);
 509     CHECK_LE(size_, new_capacity);
 510     uptr new_capacity_bytes =
 511         RoundUpTo(new_capacity * sizeof(T), GetPageSizeCached());
 512     T *new_data = (T *)MmapOrDie(new_capacity_bytes, "InternalMmapVector");
 513     internal_memcpy(new_data, data_, size_ * sizeof(T));
 514     UnmapOrDie(data_, capacity_bytes_);
 515     data_ = new_data;
 516     capacity_bytes_ = new_capacity_bytes;
 517   }
 518
 519   T *data_;
 520   uptr capacity_bytes_;
 521   uptr size_;
 522 };
 523
 524 template <typename T>
 525 bool operator==(const InternalMmapVectorNoCtor<T> &lhs,
 526                 const InternalMmapVectorNoCtor<T> &rhs) {
 527   if (lhs.size() != rhs.size()) return false;
 528   return internal_memcmp(lhs.data(), rhs.data(), lhs.size() * sizeof(T)) == 0;
 529 }
 530
 531 template <typename T>
 532 bool operator!=(const InternalMmapVectorNoCtor<T> &lhs,
 533                 const InternalMmapVectorNoCtor<T> &rhs) {
 534   return !(lhs == rhs);
 535 }
 536
 537 template<typename T>
 538 class InternalMmapVector : public InternalMmapVectorNoCtor<T> {
 539  public:
 540   InternalMmapVector() { InternalMmapVectorNoCtor<T>::Initialize(1); }
 541   explicit InternalMmapVector(uptr cnt) {
 542     InternalMmapVectorNoCtor<T>::Initialize(cnt);
 543     this->resize(cnt);
 544   }
 545   ~InternalMmapVector() { InternalMmapVectorNoCtor<T>::Destroy(); }
 546   // Disallow copies and moves.
 547   InternalMmapVector(const InternalMmapVector &) = delete;
 548   InternalMmapVector &operator=(const InternalMmapVector &) = delete;
 549   InternalMmapVector(InternalMmapVector &&) = delete;
 550   InternalMmapVector &operator=(InternalMmapVector &&) = delete;
 551 };
 552
 553 class InternalScopedString : public InternalMmapVector<char> {
 554  public:
 555   explicit InternalScopedString(uptr max_length)
 556       : InternalMmapVector<char>(max_length), length_(0) {
 557     (*this)[0] = '\0';
 558   }
 559   uptr length() { return length_; }
 560   void clear() {
 561     (*this)[0] = '\0';
 562     length_ = 0;
 563   }
 564   void append(const char *format, ...);
 565
 566  private:
 567   uptr length_;
 568 };
 569
 570 template <class T>
 571 struct CompareLess {
 572   bool operator()(const T &a, const T &b) const { return a < b; }
 573 };
 574
 575 // HeapSort for arrays and InternalMmapVector.
 576 template <class T, class Compare = CompareLess<T>>
 577 void Sort(T *v, uptr size, Compare comp = {}) {
 578   if (size < 2)
 579     return;
 580   // Stage 1: insert elements to the heap.
 581   for (uptr i = 1; i < size; i++) {
 582     uptr j, p;
 583     for (j = i; j > 0; j = p) {
 584       p = (j - 1) / 2;
 585       if (comp(v[p], v[j]))
 586         Swap(v[j], v[p]);
 587       else
 588         break;
 589     }
 590   }
 591   // Stage 2: swap largest element with the last one,
 592   // and sink the new top.
 593   for (uptr i = size - 1; i > 0; i--) {
 594     Swap(v[0], v[i]);
 595     uptr j, max_ind;
 596     for (j = 0; j < i; j = max_ind) {
 597       uptr left = 2 * j + 1;
 598       uptr right = 2 * j + 2;
 599       max_ind = j;
 600       if (left < i && comp(v[max_ind], v[left]))
 601         max_ind = left;
 602       if (right < i && comp(v[max_ind], v[right]))
 603         max_ind = right;
 604       if (max_ind != j)
 605         Swap(v[j], v[max_ind]);
 606       else
 607         break;
 608     }
 609   }
 610 }
 611
 612 // Works like std::lower_bound: finds the first element that is not less
 613 // than the val.
 614 template <class Container, class Value, class Compare>
 615 uptr InternalLowerBound(const Container &v, uptr first, uptr last,
 616                         const Value &val, Compare comp) {
 617   while (last > first) {
 618     uptr mid = (first + last) / 2;
 619     if (comp(v[mid], val))
 620       first = mid + 1;
 621     else
 622       last = mid;
 623   }
 624   return first;
 625 }
 626
 627 enum ModuleArch {
 628   kModuleArchUnknown,
 629   kModuleArchI386,
 630   kModuleArchX86_64,
 631   kModuleArchX86_64H,
 632   kModuleArchARMV6,
 633   kModuleArchARMV7,
 634   kModuleArchARMV7S,
 635   kModuleArchARMV7K,
 636   kModuleArchARM64
 637 };
 638
 639 // Opens the file 'file_name" and reads up to 'max_len' bytes.
 640 // The resulting buffer is mmaped and stored in '*buff'.
 641 // Returns true if file was successfully opened and read.
 642 bool ReadFileToVector(const char *file_name,
 643                       InternalMmapVectorNoCtor<char> *buff,
 644                       uptr max_len = 1 << 26, error_t *errno_p = nullptr);
 645
 646 // Opens the file 'file_name" and reads up to 'max_len' bytes.
 647 // This function is less I/O efficient than ReadFileToVector as it may reread
 648 // file multiple times to avoid mmap during read attempts. It's used to read
 649 // procmap, so short reads with mmap in between can produce inconsistent result.
 650 // The resulting buffer is mmaped and stored in '*buff'.
 651 // The size of the mmaped region is stored in '*buff_size'.
 652 // The total number of read bytes is stored in '*read_len'.
 653 // Returns true if file was successfully opened and read.
 654 bool ReadFileToBuffer(const char *file_name, char **buff, uptr *buff_size,
 655                       uptr *read_len, uptr max_len = 1 << 26,
 656                       error_t *errno_p = nullptr);
 657
 658 // When adding a new architecture, don't forget to also update
 659 // script/asan_symbolize.py and sanitizer_symbolizer_libcdep.cc.
 660 inline const char *ModuleArchToString(ModuleArch arch) {
 661   switch (arch) {
 662     case kModuleArchUnknown:
 663       return "";
 664     case kModuleArchI386:
 665       return "i386";
 666     case kModuleArchX86_64:
 667       return "x86_64";
 668     case kModuleArchX86_64H:
 669       return "x86_64h";
 670     case kModuleArchARMV6:
 671       return "armv6";
 672     case kModuleArchARMV7:
 673       return "armv7";
 674     case kModuleArchARMV7S:
 675       return "armv7s";
 676     case kModuleArchARMV7K:
 677       return "armv7k";
 678     case kModuleArchARM64:
 679       return "arm64";
 680   }
 681   CHECK(0 && "Invalid module arch");
 682   return "";
 683 }
 684
 685 const uptr kModuleUUIDSize = 16;
 686 const uptr kMaxSegName = 16;
 687
 688 // Represents a binary loaded into virtual memory (e.g. this can be an
 689 // executable or a shared object).
 690 class LoadedModule {
 691  public:
 692   LoadedModule()
 693       : full_name_(nullptr),
 694         base_address_(0),
 695         max_executable_address_(0),
 696         arch_(kModuleArchUnknown),
 697         instrumented_(false) {
 698     internal_memset(uuid_, 0, kModuleUUIDSize);
 699     ranges_.clear();
 700   }
 701   void set(const char *module_name, uptr base_address);
 702   void set(const char *module_name, uptr base_address, ModuleArch arch,
 703            u8 uuid[kModuleUUIDSize], bool instrumented);
 704   void clear();
 705   void addAddressRange(uptr beg, uptr end, bool executable, bool writable,
 706                        const char *name = nullptr);
 707   bool containsAddress(uptr address) const;
 708
 709   const char *full_name() const { return full_name_; }
 710   uptr base_address() const { return base_address_; }
 711   uptr max_executable_address() const { return max_executable_address_; }
 712   ModuleArch arch() const { return arch_; }
 713   const u8 *uuid() const { return uuid_; }
 714   bool instrumented() const { return instrumented_; }
 715
 716   struct AddressRange {
 717     AddressRange *next;
 718     uptr beg;
 719     uptr end;
 720     bool executable;
 721     bool writable;
 722     char name[kMaxSegName];
 723
 724     AddressRange(uptr beg, uptr end, bool executable, bool writable,
 725                  const char *name)
 726         : next(nullptr),
 727           beg(beg),
 728           end(end),
 729           executable(executable),
 730           writable(writable) {
 731       internal_strncpy(this->name, (name ? name : ""), ARRAY_SIZE(this->name));
 732     }
 733   };
 734
 735   const IntrusiveList<AddressRange> &ranges() const { return ranges_; }
 736
 737  private:
 738   char *full_name_;  // Owned.
 739   uptr base_address_;
 740   uptr max_executable_address_;
 741   ModuleArch arch_;
 742   u8 uuid_[kModuleUUIDSize];
 743   bool instrumented_;
 744   IntrusiveList<AddressRange> ranges_;
 745 };
 746
 747 // List of LoadedModules. OS-dependent implementation is responsible for
 748 // filling this information.
 749 class ListOfModules {
 750  public:
 751   ListOfModules() : initialized(false) {}
 752   ~ListOfModules() { clear(); }
 753   void init();
 754   void fallbackInit();  // Uses fallback init if available, otherwise clears
 755   const LoadedModule *begin() const { return modules_.begin(); }
 756   LoadedModule *begin() { return modules_.begin(); }
 757   const LoadedModule *end() const { return modules_.end(); }
 758   LoadedModule *end() { return modules_.end(); }
 759   uptr size() const { return modules_.size(); }
 760   const LoadedModule &operator[](uptr i) const {
 761     CHECK_LT(i, modules_.size());
 762     return modules_[i];
 763   }
 764
 765  private:
 766   void clear() {
 767     for (auto &module : modules_) module.clear();
 768     modules_.clear();
 769   }
 770   void clearOrInit() {
 771     initialized ? clear() : modules_.Initialize(kInitialCapacity);
 772     initialized = true;
 773   }
 774
 775   InternalMmapVectorNoCtor<LoadedModule> modules_;
 776   // We rarely have more than 16K loaded modules.
 777   static const uptr kInitialCapacity = 1 << 14;
 778   bool initialized;
 779 };
 780
 781 // Callback type for iterating over a set of memory ranges.
 782 typedef void (*RangeIteratorCallback)(uptr begin, uptr end, void *arg);
 783
 784 enum AndroidApiLevel {
 785   ANDROID_NOT_ANDROID = 0,
 786   ANDROID_KITKAT = 19,
 787   ANDROID_LOLLIPOP_MR1 = 22,
 788   ANDROID_POST_LOLLIPOP = 23
 789 };
 790
 791 void WriteToSyslog(const char *buffer);
 792
 793 #if SANITIZER_MAC
 794 void LogFullErrorReport(const char *buffer);
 795 #else
 796 INLINE void LogFullErrorReport(const char *buffer) {}
 797 #endif
 798
 799 #if SANITIZER_LINUX || SANITIZER_MAC
 800 void WriteOneLineToSyslog(const char *s);
 801 void LogMessageOnPrintf(const char *str);
 802 #else
 803 INLINE void WriteOneLineToSyslog(const char *s) {}
 804 INLINE void LogMessageOnPrintf(const char *str) {}
 805 #endif
 806
 807 #if SANITIZER_LINUX
 808 // Initialize Android logging. Any writes before this are silently lost.
 809 void AndroidLogInit();
 810 void SetAbortMessage(const char *);
 811 #else
 812 INLINE void AndroidLogInit() {}
 813 // FIXME: MacOS implementation could use CRSetCrashLogMessage.
 814 INLINE void SetAbortMessage(const char *) {}
 815 #endif
 816
 817 #if SANITIZER_ANDROID
 818 void SanitizerInitializeUnwinder();
 819 AndroidApiLevel AndroidGetApiLevel();
 820 #else
 821 INLINE void AndroidLogWrite(const char *buffer_unused) {}
 822 INLINE void SanitizerInitializeUnwinder() {}
 823 INLINE AndroidApiLevel AndroidGetApiLevel() { return ANDROID_NOT_ANDROID; }
 824 #endif
 825
 826 INLINE uptr GetPthreadDestructorIterations() {
 827 #if SANITIZER_ANDROID
 828   return (AndroidGetApiLevel() == ANDROID_LOLLIPOP_MR1) ? 8 : 4;
 829 #elif SANITIZER_POSIX
 830   return 4;
 831 #else
 832 // Unused on Windows.
 833   return 0;
 834 #endif
 835 }
 836
 837 void *internal_start_thread(void(*func)(void*), void *arg);
 838 void internal_join_thread(void *th);
 839 void MaybeStartBackgroudThread();
 840
 841 // Make the compiler think that something is going on there.
 842 // Use this inside a loop that looks like memset/memcpy/etc to prevent the
 843 // compiler from recognising it and turning it into an actual call to
 844 // memset/memcpy/etc.
 845 static inline void SanitizerBreakOptimization(void *arg) {
 846 #if defined(_MSC_VER) && !defined(__clang__)
 847   _ReadWriteBarrier();
 848 #else
 849   __asm__ __volatile__("" : : "r" (arg) : "memory");
 850 #endif
 851 }
 852
 853 struct SignalContext {
 854   void *siginfo;
 855   void *context;
 856   uptr addr;
 857   uptr pc;
 858   uptr sp;
 859   uptr bp;
 860   bool is_memory_access;
 861   enum WriteFlag { UNKNOWN, READ, WRITE } write_flag;
 862
 863   // VS2013 doesn't implement unrestricted unions, so we need a trivial default
 864   // constructor
 865   SignalContext() = default;
 866
 867   // Creates signal context in a platform-specific manner.
 868   // SignalContext is going to keep pointers to siginfo and context without
 869   // owning them.
 870   SignalContext(void *siginfo, void *context)
 871       : siginfo(siginfo),
 872         context(context),
 873         addr(GetAddress()),
 874         is_memory_access(IsMemoryAccess()),
 875         write_flag(GetWriteFlag()) {
 876     InitPcSpBp();
 877   }
 878
 879   static void DumpAllRegisters(void *context);
 880
 881   // Type of signal e.g. SIGSEGV or EXCEPTION_ACCESS_VIOLATION.
 882   int GetType() const;
 883
 884   // String description of the signal.
 885   const char *Describe() const;
 886
 887   // Returns true if signal is stack overflow.
 888   bool IsStackOverflow() const;
 889
 890  private:
 891   // Platform specific initialization.
 892   void InitPcSpBp();
 893   uptr GetAddress() const;
 894   WriteFlag GetWriteFlag() const;
 895   bool IsMemoryAccess() const;
 896 };
 897
 898 void MaybeReexec();
 899
 900 template <typename Fn>
 901 class RunOnDestruction {
 902  public:
 903   explicit RunOnDestruction(Fn fn) : fn_(fn) {}
 904   ~RunOnDestruction() { fn_(); }
 905
 906  private:
 907   Fn fn_;
 908 };
 909
 910 // A simple scope guard. Usage:
 911 // auto cleanup = at_scope_exit([]{ do_cleanup; });
 912 template <typename Fn>
 913 RunOnDestruction<Fn> at_scope_exit(Fn fn) {
 914   return RunOnDestruction<Fn>(fn);
 915 }
 916
 917 // Linux on 64-bit s390 had a nasty bug that crashes the whole machine
 918 // if a process uses virtual memory over 4TB (as many sanitizers like
 919 // to do).  This function will abort the process if running on a kernel
 920 // that looks vulnerable.
 921 #if SANITIZER_LINUX && SANITIZER_S390_64
 922 void AvoidCVE_2016_2143();
 923 #else
 924 INLINE void AvoidCVE_2016_2143() {}
 925 #endif
 926
 927 struct StackDepotStats {
 928   uptr n_uniq_ids;
 929   uptr allocated;
 930 };
 931
 932 // The default value for allocator_release_to_os_interval_ms common flag to
 933 // indicate that sanitizer allocator should not attempt to release memory to OS.
 934 const s32 kReleaseToOSIntervalNever = -1;
 935
 936 void CheckNoDeepBind(const char *filename, int flag);
 937
 938 // Returns the requested amount of random data (up to 256 bytes) that can then
 939 // be used to seed a PRNG. Defaults to blocking like the underlying syscall.
 940 bool GetRandom(void *buffer, uptr length, bool blocking = true);
 941
 942 // Returns the number of logical processors on the system.
 943 u32 GetNumberOfCPUs();
 944 extern u32 NumberOfCPUsCached;
 945 INLINE u32 GetNumberOfCPUsCached() {
 946   if (!NumberOfCPUsCached)
 947     NumberOfCPUsCached = GetNumberOfCPUs();
 948   return NumberOfCPUsCached;
 949 }
 950
 951 }  // namespace __sanitizer
 952
 953 inline void *operator new(__sanitizer::operator_new_size_type size,
 954                           __sanitizer::LowLevelAllocator &alloc) {
 955   return alloc.Allocate(size);
 956 }
 957
 958 #endif  // SANITIZER_COMMON_H