libsanitizer/sanitizer_common/sanitizer_fuchsia.cc

   1 //===-- sanitizer_fuchsia.cc ---------------------------------------------===//
   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 AddressSanitizer and other sanitizer
   9 // run-time libraries and implements Fuchsia-specific functions from
  10 // sanitizer_common.h.
  11 //===---------------------------------------------------------------------===//
  12
  13 #include "sanitizer_fuchsia.h"
  14 #if SANITIZER_FUCHSIA
  15
  16 #include "sanitizer_common.h"
  17 #include "sanitizer_libc.h"
  18 #include "sanitizer_mutex.h"
  19 #include "sanitizer_stacktrace.h"
  20
  21 #include <limits.h>
  22 #include <pthread.h>
  23 #include <stdlib.h>
  24 #include <unistd.h>
  25 #include <unwind.h>
  26 #include <zircon/errors.h>
  27 #include <zircon/process.h>
  28 #include <zircon/syscalls.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_nanosleep(0);
  36   CHECK_EQ(status, ZX_OK);
  37   return 0;  // Why doesn't this return void?
  38 }
  39
  40 static void internal_nanosleep(zx_time_t ns) {
  41   zx_status_t status = _zx_nanosleep(_zx_deadline_after(ns));
  42   CHECK_EQ(status, ZX_OK);
  43 }
  44
  45 unsigned int internal_sleep(unsigned int seconds) {
  46   internal_nanosleep(ZX_SEC(seconds));
  47   return 0;
  48 }
  49
  50 u64 NanoTime() { return _zx_time_get(ZX_CLOCK_UTC); }
  51
  52 uptr internal_getpid() {
  53   zx_info_handle_basic_t info;
  54   zx_status_t status =
  55       _zx_object_get_info(_zx_process_self(), ZX_INFO_HANDLE_BASIC, &info,
  56                           sizeof(info), NULL, NULL);
  57   CHECK_EQ(status, ZX_OK);
  58   uptr pid = static_cast<uptr>(info.koid);
  59   CHECK_EQ(pid, info.koid);
  60   return pid;
  61 }
  62
  63 uptr GetThreadSelf() { return reinterpret_cast<uptr>(thrd_current()); }
  64
  65 uptr GetTid() { return GetThreadSelf(); }
  66
  67 void Abort() { abort(); }
  68
  69 int Atexit(void (*function)(void)) { return atexit(function); }
  70
  71 void SleepForSeconds(int seconds) { internal_sleep(seconds); }
  72
  73 void SleepForMillis(int millis) { internal_nanosleep(ZX_MSEC(millis)); }
  74
  75 void GetThreadStackTopAndBottom(bool, uptr *stack_top, uptr *stack_bottom) {
  76   pthread_attr_t attr;
  77   CHECK_EQ(pthread_getattr_np(pthread_self(), &attr), 0);
  78   void *base;
  79   size_t size;
  80   CHECK_EQ(pthread_attr_getstack(&attr, &base, &size), 0);
  81   CHECK_EQ(pthread_attr_destroy(&attr), 0);
  82
  83   *stack_bottom = reinterpret_cast<uptr>(base);
  84   *stack_top = *stack_bottom + size;
  85 }
  86
  87 void MaybeReexec() {}
  88 void PrepareForSandboxing(__sanitizer_sandbox_arguments *args) {}
  89 void DisableCoreDumperIfNecessary() {}
  90 void InstallDeadlySignalHandlers(SignalHandlerType handler) {}
  91 void StartReportDeadlySignal() {}
  92 void ReportDeadlySignal(const SignalContext &sig, u32 tid,
  93                         UnwindSignalStackCallbackType unwind,
  94                         const void *unwind_context) {}
  95 void SetAlternateSignalStack() {}
  96 void UnsetAlternateSignalStack() {}
  97 void InitTlsSize() {}
  98
  99 void PrintModuleMap() {}
 100
 101 bool SignalContext::IsStackOverflow() const { return false; }
 102 void SignalContext::DumpAllRegisters(void *context) { UNIMPLEMENTED(); }
 103 const char *SignalContext::Describe() const { UNIMPLEMENTED(); }
 104
 105 struct UnwindTraceArg {
 106   BufferedStackTrace *stack;
 107   u32 max_depth;
 108 };
 109
 110 _Unwind_Reason_Code Unwind_Trace(struct _Unwind_Context *ctx, void *param) {
 111   UnwindTraceArg *arg = static_cast<UnwindTraceArg *>(param);
 112   CHECK_LT(arg->stack->size, arg->max_depth);
 113   uptr pc = _Unwind_GetIP(ctx);
 114   if (pc < PAGE_SIZE) return _URC_NORMAL_STOP;
 115   arg->stack->trace_buffer[arg->stack->size++] = pc;
 116   return (arg->stack->size == arg->max_depth ? _URC_NORMAL_STOP
 117                                              : _URC_NO_REASON);
 118 }
 119
 120 void BufferedStackTrace::SlowUnwindStack(uptr pc, u32 max_depth) {
 121   CHECK_GE(max_depth, 2);
 122   size = 0;
 123   UnwindTraceArg arg = {this, Min(max_depth + 1, kStackTraceMax)};
 124   _Unwind_Backtrace(Unwind_Trace, &arg);
 125   CHECK_GT(size, 0);
 126   // We need to pop a few frames so that pc is on top.
 127   uptr to_pop = LocatePcInTrace(pc);
 128   // trace_buffer[0] belongs to the current function so we always pop it,
 129   // unless there is only 1 frame in the stack trace (1 frame is always better
 130   // than 0!).
 131   PopStackFrames(Min(to_pop, static_cast<uptr>(1)));
 132   trace_buffer[0] = pc;
 133 }
 134
 135 void BufferedStackTrace::SlowUnwindStackWithContext(uptr pc, void *context,
 136                                                     u32 max_depth) {
 137   CHECK_NE(context, nullptr);
 138   UNREACHABLE("signal context doesn't exist");
 139 }
 140
 141 enum MutexState : int { MtxUnlocked = 0, MtxLocked = 1, MtxSleeping = 2 };
 142
 143 BlockingMutex::BlockingMutex() {
 144   // NOTE!  It's important that this use internal_memset, because plain
 145   // memset might be intercepted (e.g., actually be __asan_memset).
 146   // Defining this so the compiler initializes each field, e.g.:
 147   //   BlockingMutex::BlockingMutex() : BlockingMutex(LINKER_INITIALIZED) {}
 148   // might result in the compiler generating a call to memset, which would
 149   // have the same problem.
 150   internal_memset(this, 0, sizeof(*this));
 151 }
 152
 153 void BlockingMutex::Lock() {
 154   CHECK_EQ(owner_, 0);
 155   atomic_uint32_t *m = reinterpret_cast<atomic_uint32_t *>(&opaque_storage_);
 156   if (atomic_exchange(m, MtxLocked, memory_order_acquire) == MtxUnlocked)
 157     return;
 158   while (atomic_exchange(m, MtxSleeping, memory_order_acquire) != MtxUnlocked) {
 159     zx_status_t status = _zx_futex_wait(reinterpret_cast<zx_futex_t *>(m),
 160                                         MtxSleeping, ZX_TIME_INFINITE);
 161     if (status != ZX_ERR_BAD_STATE)  // Normal race.
 162       CHECK_EQ(status, ZX_OK);
 163   }
 164 }
 165
 166 void BlockingMutex::Unlock() {
 167   atomic_uint32_t *m = reinterpret_cast<atomic_uint32_t *>(&opaque_storage_);
 168   u32 v = atomic_exchange(m, MtxUnlocked, memory_order_release);
 169   CHECK_NE(v, MtxUnlocked);
 170   if (v == MtxSleeping) {
 171     zx_status_t status = _zx_futex_wake(reinterpret_cast<zx_futex_t *>(m), 1);
 172     CHECK_EQ(status, ZX_OK);
 173   }
 174 }
 175
 176 void BlockingMutex::CheckLocked() {
 177   atomic_uint32_t *m = reinterpret_cast<atomic_uint32_t *>(&opaque_storage_);
 178   CHECK_NE(MtxUnlocked, atomic_load(m, memory_order_relaxed));
 179 }
 180
 181 uptr GetPageSize() { return PAGE_SIZE; }
 182
 183 uptr GetMmapGranularity() { return PAGE_SIZE; }
 184
 185 sanitizer_shadow_bounds_t ShadowBounds;
 186
 187 uptr GetMaxVirtualAddress() {
 188   ShadowBounds = __sanitizer_shadow_bounds();
 189   return ShadowBounds.memory_limit - 1;
 190 }
 191
 192 static void *DoAnonymousMmapOrDie(uptr size, const char *mem_type,
 193                                   bool raw_report, bool die_for_nomem) {
 194   size = RoundUpTo(size, PAGE_SIZE);
 195
 196   zx_handle_t vmo;
 197   zx_status_t status = _zx_vmo_create(size, 0, &vmo);
 198   if (status != ZX_OK) {
 199     if (status != ZX_ERR_NO_MEMORY || die_for_nomem)
 200       ReportMmapFailureAndDie(size, mem_type, "zx_vmo_create", status,
 201                               raw_report);
 202     return nullptr;
 203   }
 204   _zx_object_set_property(vmo, ZX_PROP_NAME, mem_type,
 205                           internal_strlen(mem_type));
 206
 207   // TODO(mcgrathr): Maybe allocate a VMAR for all sanitizer heap and use that?
 208   uintptr_t addr;
 209   status = _zx_vmar_map(_zx_vmar_root_self(), 0, vmo, 0, size,
 210                         ZX_VM_FLAG_PERM_READ | ZX_VM_FLAG_PERM_WRITE, &addr);
 211   _zx_handle_close(vmo);
 212
 213   if (status != ZX_OK) {
 214     if (status != ZX_ERR_NO_MEMORY || die_for_nomem)
 215       ReportMmapFailureAndDie(size, mem_type, "zx_vmar_map", status,
 216                               raw_report);
 217     return nullptr;
 218   }
 219
 220   IncreaseTotalMmap(size);
 221
 222   return reinterpret_cast<void *>(addr);
 223 }
 224
 225 void *MmapOrDie(uptr size, const char *mem_type, bool raw_report) {
 226   return DoAnonymousMmapOrDie(size, mem_type, raw_report, true);
 227 }
 228
 229 void *MmapNoReserveOrDie(uptr size, const char *mem_type) {
 230   return MmapOrDie(size, mem_type);
 231 }
 232
 233 void *MmapOrDieOnFatalError(uptr size, const char *mem_type) {
 234   return DoAnonymousMmapOrDie(size, mem_type, false, false);
 235 }
 236
 237 // MmapNoAccess and MmapFixedOrDie are used only by sanitizer_allocator.
 238 // Instead of doing exactly what they say, we make MmapNoAccess actually
 239 // just allocate a VMAR to reserve the address space.  Then MmapFixedOrDie
 240 // uses that VMAR instead of the root.
 241
 242 zx_handle_t allocator_vmar = ZX_HANDLE_INVALID;
 243 uintptr_t allocator_vmar_base;
 244 size_t allocator_vmar_size;
 245
 246 void *MmapNoAccess(uptr size) {
 247   size = RoundUpTo(size, PAGE_SIZE);
 248   CHECK_EQ(allocator_vmar, ZX_HANDLE_INVALID);
 249   uintptr_t base;
 250   zx_status_t status =
 251       _zx_vmar_allocate(_zx_vmar_root_self(), 0, size,
 252                         ZX_VM_FLAG_CAN_MAP_READ | ZX_VM_FLAG_CAN_MAP_WRITE |
 253                             ZX_VM_FLAG_CAN_MAP_SPECIFIC,
 254                         &allocator_vmar, &base);
 255   if (status != ZX_OK)
 256     ReportMmapFailureAndDie(size, "sanitizer allocator address space",
 257                             "zx_vmar_allocate", status);
 258
 259   allocator_vmar_base = base;
 260   allocator_vmar_size = size;
 261   return reinterpret_cast<void *>(base);
 262 }
 263
 264 constexpr const char kAllocatorVmoName[] = "sanitizer_allocator";
 265
 266 static void *DoMmapFixedOrDie(uptr fixed_addr, uptr size, bool die_for_nomem) {
 267   size = RoundUpTo(size, PAGE_SIZE);
 268
 269   zx_handle_t vmo;
 270   zx_status_t status = _zx_vmo_create(size, 0, &vmo);
 271   if (status != ZX_OK) {
 272     if (status != ZX_ERR_NO_MEMORY || die_for_nomem)
 273       ReportMmapFailureAndDie(size, kAllocatorVmoName, "zx_vmo_create", status);
 274     return nullptr;
 275   }
 276   _zx_object_set_property(vmo, ZX_PROP_NAME, kAllocatorVmoName,
 277                           sizeof(kAllocatorVmoName) - 1);
 278
 279   DCHECK_GE(fixed_addr, allocator_vmar_base);
 280   uintptr_t offset = fixed_addr - allocator_vmar_base;
 281   DCHECK_LE(size, allocator_vmar_size);
 282   DCHECK_GE(allocator_vmar_size - offset, size);
 283
 284   uintptr_t addr;
 285   status = _zx_vmar_map(
 286       allocator_vmar, offset, vmo, 0, size,
 287       ZX_VM_FLAG_PERM_READ | ZX_VM_FLAG_PERM_WRITE | ZX_VM_FLAG_SPECIFIC,
 288       &addr);
 289   _zx_handle_close(vmo);
 290   if (status != ZX_OK) {
 291     if (status != ZX_ERR_NO_MEMORY || die_for_nomem)
 292       ReportMmapFailureAndDie(size, kAllocatorVmoName, "zx_vmar_map", status);
 293     return nullptr;
 294   }
 295
 296   IncreaseTotalMmap(size);
 297
 298   return reinterpret_cast<void *>(addr);
 299 }
 300
 301 void *MmapFixedOrDie(uptr fixed_addr, uptr size) {
 302   return DoMmapFixedOrDie(fixed_addr, size, true);
 303 }
 304
 305 void *MmapFixedOrDieOnFatalError(uptr fixed_addr, uptr size) {
 306   return DoMmapFixedOrDie(fixed_addr, size, false);
 307 }
 308
 309 // This should never be called.
 310 void *MmapFixedNoAccess(uptr fixed_addr, uptr size, const char *name) {
 311   UNIMPLEMENTED();
 312 }
 313
 314 void *MmapAlignedOrDieOnFatalError(uptr size, uptr alignment,
 315                                    const char *mem_type) {
 316   CHECK_GE(size, PAGE_SIZE);
 317   CHECK(IsPowerOfTwo(size));
 318   CHECK(IsPowerOfTwo(alignment));
 319
 320   zx_handle_t vmo;
 321   zx_status_t status = _zx_vmo_create(size, 0, &vmo);
 322   if (status != ZX_OK) {
 323     if (status != ZX_ERR_NO_MEMORY)
 324       ReportMmapFailureAndDie(size, mem_type, "zx_vmo_create", status, false);
 325     return nullptr;
 326   }
 327   _zx_object_set_property(vmo, ZX_PROP_NAME, mem_type,
 328                           internal_strlen(mem_type));
 329
 330   // TODO(mcgrathr): Maybe allocate a VMAR for all sanitizer heap and use that?
 331
 332   // Map a larger size to get a chunk of address space big enough that
 333   // it surely contains an aligned region of the requested size.  Then
 334   // overwrite the aligned middle portion with a mapping from the
 335   // beginning of the VMO, and unmap the excess before and after.
 336   size_t map_size = size + alignment;
 337   uintptr_t addr;
 338   status = _zx_vmar_map(_zx_vmar_root_self(), 0, vmo, 0, map_size,
 339                         ZX_VM_FLAG_PERM_READ | ZX_VM_FLAG_PERM_WRITE, &addr);
 340   if (status == ZX_OK) {
 341     uintptr_t map_addr = addr;
 342     uintptr_t map_end = map_addr + map_size;
 343     addr = RoundUpTo(map_addr, alignment);
 344     uintptr_t end = addr + size;
 345     if (addr != map_addr) {
 346       zx_info_vmar_t info;
 347       status = _zx_object_get_info(_zx_vmar_root_self(), ZX_INFO_VMAR, &info,
 348                                    sizeof(info), NULL, NULL);
 349       if (status == ZX_OK) {
 350         uintptr_t new_addr;
 351         status =
 352             _zx_vmar_map(_zx_vmar_root_self(), addr - info.base, vmo, 0, size,
 353                          ZX_VM_FLAG_PERM_READ | ZX_VM_FLAG_PERM_WRITE |
 354                              ZX_VM_FLAG_SPECIFIC_OVERWRITE,
 355                          &new_addr);
 356         if (status == ZX_OK) CHECK_EQ(new_addr, addr);
 357       }
 358     }
 359     if (status == ZX_OK && addr != map_addr)
 360       status = _zx_vmar_unmap(_zx_vmar_root_self(), map_addr, addr - map_addr);
 361     if (status == ZX_OK && end != map_end)
 362       status = _zx_vmar_unmap(_zx_vmar_root_self(), end, map_end - end);
 363   }
 364   _zx_handle_close(vmo);
 365
 366   if (status != ZX_OK) {
 367     if (status != ZX_ERR_NO_MEMORY)
 368       ReportMmapFailureAndDie(size, mem_type, "zx_vmar_map", status, false);
 369     return nullptr;
 370   }
 371
 372   IncreaseTotalMmap(size);
 373
 374   return reinterpret_cast<void *>(addr);
 375 }
 376
 377 void UnmapOrDie(void *addr, uptr size) {
 378   if (!addr || !size) return;
 379   size = RoundUpTo(size, PAGE_SIZE);
 380
 381   zx_status_t status = _zx_vmar_unmap(_zx_vmar_root_self(),
 382                                       reinterpret_cast<uintptr_t>(addr), size);
 383   if (status != ZX_OK) {
 384     Report("ERROR: %s failed to deallocate 0x%zx (%zd) bytes at address %p\n",
 385            SanitizerToolName, size, size, addr);
 386     CHECK("unable to unmap" && 0);
 387   }
 388
 389   DecreaseTotalMmap(size);
 390 }
 391
 392 // This is used on the shadow mapping, which cannot be changed.
 393 // Zircon doesn't have anything like MADV_DONTNEED.
 394 void ReleaseMemoryPagesToOS(uptr beg, uptr end) {}
 395
 396 void DumpProcessMap() {
 397   UNIMPLEMENTED();  // TODO(mcgrathr): write it
 398 }
 399
 400 bool IsAccessibleMemoryRange(uptr beg, uptr size) {
 401   // TODO(mcgrathr): Figure out a better way.
 402   zx_handle_t vmo;
 403   zx_status_t status = _zx_vmo_create(size, 0, &vmo);
 404   if (status == ZX_OK) {
 405     while (size > 0) {
 406       size_t wrote;
 407       status = _zx_vmo_write(vmo, reinterpret_cast<const void *>(beg), 0, size,
 408                              &wrote);
 409       if (status != ZX_OK) break;
 410       CHECK_GT(wrote, 0);
 411       CHECK_LE(wrote, size);
 412       beg += wrote;
 413       size -= wrote;
 414     }
 415     _zx_handle_close(vmo);
 416   }
 417   return status == ZX_OK;
 418 }
 419
 420 // FIXME implement on this platform.
 421 void GetMemoryProfile(fill_profile_f cb, uptr *stats, uptr stats_size) {}
 422
 423 bool ReadFileToBuffer(const char *file_name, char **buff, uptr *buff_size,
 424                       uptr *read_len, uptr max_len, error_t *errno_p) {
 425   zx_handle_t vmo;
 426   zx_status_t status = __sanitizer_get_configuration(file_name, &vmo);
 427   if (status == ZX_OK) {
 428     uint64_t vmo_size;
 429     status = _zx_vmo_get_size(vmo, &vmo_size);
 430     if (status == ZX_OK) {
 431       if (vmo_size < max_len) max_len = vmo_size;
 432       size_t map_size = RoundUpTo(max_len, PAGE_SIZE);
 433       uintptr_t addr;
 434       status = _zx_vmar_map(_zx_vmar_root_self(), 0, vmo, 0, map_size,
 435                             ZX_VM_FLAG_PERM_READ, &addr);
 436       if (status == ZX_OK) {
 437         *buff = reinterpret_cast<char *>(addr);
 438         *buff_size = map_size;
 439         *read_len = max_len;
 440       }
 441     }
 442     _zx_handle_close(vmo);
 443   }
 444   if (status != ZX_OK && errno_p) *errno_p = status;
 445   return status == ZX_OK;
 446 }
 447
 448 void RawWrite(const char *buffer) {
 449   __sanitizer_log_write(buffer, internal_strlen(buffer));
 450 }
 451
 452 void CatastrophicErrorWrite(const char *buffer, uptr length) {
 453   __sanitizer_log_write(buffer, length);
 454 }
 455
 456 char **StoredArgv;
 457 char **StoredEnviron;
 458
 459 char **GetArgv() { return StoredArgv; }
 460
 461 const char *GetEnv(const char *name) {
 462   if (StoredEnviron) {
 463     uptr NameLen = internal_strlen(name);
 464     for (char **Env = StoredEnviron; *Env != 0; Env++) {
 465       if (internal_strncmp(*Env, name, NameLen) == 0 && (*Env)[NameLen] == '=')
 466         return (*Env) + NameLen + 1;
 467     }
 468   }
 469   return nullptr;
 470 }
 471
 472 uptr ReadBinaryName(/*out*/ char *buf, uptr buf_len) {
 473   const char *argv0 = StoredArgv[0];
 474   if (!argv0) argv0 = "<UNKNOWN>";
 475   internal_strncpy(buf, argv0, buf_len);
 476   return internal_strlen(buf);
 477 }
 478
 479 uptr ReadLongProcessName(/*out*/ char *buf, uptr buf_len) {
 480   return ReadBinaryName(buf, buf_len);
 481 }
 482
 483 uptr MainThreadStackBase, MainThreadStackSize;
 484
 485 bool GetRandom(void *buffer, uptr length, bool blocking) {
 486   CHECK_LE(length, ZX_CPRNG_DRAW_MAX_LEN);
 487   size_t size;
 488   CHECK_EQ(_zx_cprng_draw(buffer, length, &size), ZX_OK);
 489   CHECK_EQ(size, length);
 490   return true;
 491 }
 492
 493 }  // namespace __sanitizer
 494
 495 using namespace __sanitizer;  // NOLINT
 496
 497 extern "C" {
 498 void __sanitizer_startup_hook(int argc, char **argv, char **envp,
 499                               void *stack_base, size_t stack_size) {
 500   __sanitizer::StoredArgv = argv;
 501   __sanitizer::StoredEnviron = envp;
 502   __sanitizer::MainThreadStackBase = reinterpret_cast<uintptr_t>(stack_base);
 503   __sanitizer::MainThreadStackSize = stack_size;
 504 }
 505
 506 void __sanitizer_set_report_path(const char *path) {
 507   // Handle the initialization code in each sanitizer, but no other calls.
 508   // This setting is never consulted on Fuchsia.
 509   DCHECK_EQ(path, common_flags()->log_path);
 510 }
 511
 512 void __sanitizer_set_report_fd(void *fd) {
 513   UNREACHABLE("not available on Fuchsia");
 514 }
 515 }  // extern "C"
 516
 517 #endif  // SANITIZER_FUCHSIA