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1//===-- msan.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-exception6//7//===----------------------------------------------------------------------===//8//9// This file is a part of MemorySanitizer.10//11// MemorySanitizer runtime.12//===----------------------------------------------------------------------===//13 14#include "msan.h"15 16#include "msan_chained_origin_depot.h"17#include "msan_origin.h"18#include "msan_poisoning.h"19#include "msan_report.h"20#include "msan_thread.h"21#include "sanitizer_common/sanitizer_atomic.h"22#include "sanitizer_common/sanitizer_common.h"23#include "sanitizer_common/sanitizer_flag_parser.h"24#include "sanitizer_common/sanitizer_flags.h"25#include "sanitizer_common/sanitizer_interface_internal.h"26#include "sanitizer_common/sanitizer_libc.h"27#include "sanitizer_common/sanitizer_procmaps.h"28#include "sanitizer_common/sanitizer_stackdepot.h"29#include "sanitizer_common/sanitizer_stacktrace.h"30#include "sanitizer_common/sanitizer_symbolizer.h"31#include "ubsan/ubsan_flags.h"32#include "ubsan/ubsan_init.h"33 34// ACHTUNG! No system header includes in this file.35 36using namespace __sanitizer;37 38// Globals.39static THREADLOCAL int msan_expect_umr = 0;40static THREADLOCAL int msan_expected_umr_found = 0;41 42// Function argument shadow. Each argument starts at the next available 8-byte43// aligned address.44SANITIZER_INTERFACE_ATTRIBUTE45THREADLOCAL u64 __msan_param_tls[kMsanParamTlsSize / sizeof(u64)];46 47// Function argument origin. Each argument starts at the same offset as the48// corresponding shadow in (__msan_param_tls). Slightly weird, but changing this49// would break compatibility with older prebuilt binaries.50SANITIZER_INTERFACE_ATTRIBUTE51THREADLOCAL u32 __msan_param_origin_tls[kMsanParamTlsSize / sizeof(u32)];52 53SANITIZER_INTERFACE_ATTRIBUTE54THREADLOCAL u64 __msan_retval_tls[kMsanRetvalTlsSize / sizeof(u64)];55 56SANITIZER_INTERFACE_ATTRIBUTE57THREADLOCAL u32 __msan_retval_origin_tls;58 59alignas(16) SANITIZER_INTERFACE_ATTRIBUTE THREADLOCAL u6460    __msan_va_arg_tls[kMsanParamTlsSize / sizeof(u64)];61 62alignas(16) SANITIZER_INTERFACE_ATTRIBUTE THREADLOCAL u3263    __msan_va_arg_origin_tls[kMsanParamTlsSize / sizeof(u32)];64 65SANITIZER_INTERFACE_ATTRIBUTE66THREADLOCAL uptr __msan_va_arg_overflow_size_tls;67 68SANITIZER_INTERFACE_ATTRIBUTE69THREADLOCAL u32 __msan_origin_tls;70 71extern "C" SANITIZER_WEAK_ATTRIBUTE const int __msan_track_origins;72 73int __msan_get_track_origins() {74  return &__msan_track_origins ? __msan_track_origins : 0;75}76 77extern "C" SANITIZER_WEAK_ATTRIBUTE const int __msan_keep_going;78 79namespace __msan {80 81static THREADLOCAL int is_in_symbolizer_or_unwinder;82static void EnterSymbolizerOrUnwider() { ++is_in_symbolizer_or_unwinder; }83static void ExitSymbolizerOrUnwider() { --is_in_symbolizer_or_unwinder; }84bool IsInSymbolizerOrUnwider() { return is_in_symbolizer_or_unwinder; }85 86struct UnwinderScope {87  UnwinderScope() { EnterSymbolizerOrUnwider(); }88  ~UnwinderScope() { ExitSymbolizerOrUnwider(); }89};90 91static Flags msan_flags;92 93Flags *flags() { return &msan_flags; }94 95int msan_inited = 0;96bool msan_init_is_running;97 98int msan_report_count = 0;99 100// Array of stack origins.101// FIXME: make it resizable.102// Although BSS memory doesn't cost anything until used, it is limited to 2GB103// in some configurations (e.g., "relocation R_X86_64_PC32 out of range:104// ... is not in [-2147483648, 2147483647]; references section '.bss'").105// We use kNumStackOriginDescrs * (sizeof(char*) + sizeof(uptr)) == 64MB.106#if SANITIZER_PPC107// soft_rss_limit test (release_origin.c) fails on PPC if kNumStackOriginDescrs108// is too high109static const uptr kNumStackOriginDescrs = 1 * 1024 * 1024;110#else111static const uptr kNumStackOriginDescrs = 4 * 1024 * 1024;112#endif  // SANITIZER_PPC113static const char *StackOriginDescr[kNumStackOriginDescrs];114static uptr StackOriginPC[kNumStackOriginDescrs];115static atomic_uint32_t NumStackOriginDescrs;116 117void Flags::SetDefaults() {118#define MSAN_FLAG(Type, Name, DefaultValue, Description) Name = DefaultValue;119#include "msan_flags.inc"120#undef MSAN_FLAG121}122 123// keep_going is an old name for halt_on_error,124// and it has inverse meaning.125class FlagHandlerKeepGoing final : public FlagHandlerBase {126  bool *halt_on_error_;127 128 public:129  explicit FlagHandlerKeepGoing(bool *halt_on_error)130      : halt_on_error_(halt_on_error) {}131  bool Parse(const char *value) final {132    bool tmp;133    FlagHandler<bool> h(&tmp);134    if (!h.Parse(value)) return false;135    *halt_on_error_ = !tmp;136    return true;137  }138  bool Format(char *buffer, uptr size) final {139    const char *keep_going_str = (*halt_on_error_) ? "false" : "true";140    return FormatString(buffer, size, keep_going_str);141  }142};143 144static void RegisterMsanFlags(FlagParser *parser, Flags *f) {145#define MSAN_FLAG(Type, Name, DefaultValue, Description) \146  RegisterFlag(parser, #Name, Description, &f->Name);147#include "msan_flags.inc"148#undef MSAN_FLAG149 150  FlagHandlerKeepGoing *fh_keep_going = new (GetGlobalLowLevelAllocator())151      FlagHandlerKeepGoing(&f->halt_on_error);152  parser->RegisterHandler("keep_going", fh_keep_going,153                          "deprecated, use halt_on_error");154}155 156static void InitializeFlags() {157  SetCommonFlagsDefaults();158  {159    CommonFlags cf;160    cf.CopyFrom(*common_flags());161    cf.external_symbolizer_path = GetEnv("MSAN_SYMBOLIZER_PATH");162    cf.malloc_context_size = 20;163    cf.handle_ioctl = true;164    // FIXME: test and enable.165    cf.check_printf = false;166    cf.intercept_tls_get_addr = true;167    OverrideCommonFlags(cf);168  }169 170  Flags *f = flags();171  f->SetDefaults();172 173  FlagParser parser;174  RegisterMsanFlags(&parser, f);175  RegisterCommonFlags(&parser);176 177#if MSAN_CONTAINS_UBSAN178  __ubsan::Flags *uf = __ubsan::flags();179  uf->SetDefaults();180 181  FlagParser ubsan_parser;182  __ubsan::RegisterUbsanFlags(&ubsan_parser, uf);183  RegisterCommonFlags(&ubsan_parser);184#endif185 186  // Override from user-specified string.187  parser.ParseString(__msan_default_options());188#if MSAN_CONTAINS_UBSAN189  const char *ubsan_default_options = __ubsan_default_options();190  ubsan_parser.ParseString(ubsan_default_options);191#endif192 193  parser.ParseStringFromEnv("MSAN_OPTIONS");194#if MSAN_CONTAINS_UBSAN195  ubsan_parser.ParseStringFromEnv("UBSAN_OPTIONS");196#endif197 198  InitializeCommonFlags();199 200  if (Verbosity()) ReportUnrecognizedFlags();201 202  if (common_flags()->help) parser.PrintFlagDescriptions();203 204  // Check if deprecated exit_code MSan flag is set.205  if (f->exit_code != -1) {206    if (Verbosity())207      Printf("MSAN_OPTIONS=exit_code is deprecated! "208             "Please use MSAN_OPTIONS=exitcode instead.\n");209    CommonFlags cf;210    cf.CopyFrom(*common_flags());211    cf.exitcode = f->exit_code;212    OverrideCommonFlags(cf);213  }214 215  // Check flag values:216  if (f->origin_history_size < 0 ||217      f->origin_history_size > Origin::kMaxDepth) {218    Printf(219        "Origin history size invalid: %d. Must be 0 (unlimited) or in [1, %d] "220        "range.\n",221        f->origin_history_size, Origin::kMaxDepth);222    Die();223  }224  // Limiting to kStackDepotMaxUseCount / 2 to avoid overflow in225  // StackDepotHandle::inc_use_count_unsafe.226  if (f->origin_history_per_stack_limit < 0 ||227      f->origin_history_per_stack_limit > kStackDepotMaxUseCount / 2) {228    Printf(229        "Origin per-stack limit invalid: %d. Must be 0 (unlimited) or in [1, "230        "%d] range.\n",231        f->origin_history_per_stack_limit, kStackDepotMaxUseCount / 2);232    Die();233  }234  if (f->store_context_size < 1) f->store_context_size = 1;235}236 237void PrintWarningWithOrigin(uptr pc, uptr bp, u32 origin) {238  if (msan_expect_umr) {239    // Printf("Expected UMR\n");240    __msan_origin_tls = origin;241    msan_expected_umr_found = 1;242    return;243  }244 245  ++msan_report_count;246 247  GET_FATAL_STACK_TRACE_PC_BP(pc, bp);248 249  u32 report_origin =250    (__msan_get_track_origins() && Origin::isValidId(origin)) ? origin : 0;251  ReportUMR(&stack, report_origin);252 253  if (__msan_get_track_origins() && !Origin::isValidId(origin)) {254    Printf(255        "  ORIGIN: invalid (%x). Might be a bug in MemorySanitizer origin "256        "tracking.\n    This could still be a bug in your code, too!\n",257        origin);258  }259}260 261void UnpoisonParam(uptr n) {262  internal_memset(__msan_param_tls, 0, n * sizeof(*__msan_param_tls));263}264 265// Backup MSan runtime TLS state.266// Implementation must be async-signal-safe.267// Instances of this class may live on the signal handler stack, and data size268// may be an issue.269void ScopedThreadLocalStateBackup::Backup() {270  va_arg_overflow_size_tls = __msan_va_arg_overflow_size_tls;271}272 273void ScopedThreadLocalStateBackup::Restore() {274  // A lame implementation that only keeps essential state and resets the rest.275  __msan_va_arg_overflow_size_tls = va_arg_overflow_size_tls;276 277  internal_memset(__msan_param_tls, 0, sizeof(__msan_param_tls));278  internal_memset(__msan_retval_tls, 0, sizeof(__msan_retval_tls));279  internal_memset(__msan_va_arg_tls, 0, sizeof(__msan_va_arg_tls));280  internal_memset(__msan_va_arg_origin_tls, 0,281                  sizeof(__msan_va_arg_origin_tls));282 283  if (__msan_get_track_origins()) {284    internal_memset(&__msan_retval_origin_tls, 0,285                    sizeof(__msan_retval_origin_tls));286    internal_memset(__msan_param_origin_tls, 0,287                    sizeof(__msan_param_origin_tls));288  }289}290 291void UnpoisonThreadLocalState() {292}293 294const char *GetStackOriginDescr(u32 id, uptr *pc) {295  CHECK_LT(id, kNumStackOriginDescrs);296  if (pc) *pc = StackOriginPC[id];297  return StackOriginDescr[id];298}299 300u32 ChainOrigin(u32 id, StackTrace *stack) {301  MsanThread *t = GetCurrentThread();302  if (t && t->InSignalHandler())303    return id;304 305  Origin o = Origin::FromRawId(id);306  stack->tag = StackTrace::TAG_UNKNOWN;307  Origin chained = Origin::CreateChainedOrigin(o, stack);308  return chained.raw_id();309}310 311// Current implementation separates the 'id_ptr' from the 'descr' and makes312// 'descr' constant.313// Previous implementation 'descr' is created at compile time and contains314// '----' in the beginning.  When we see descr for the first time we replace315// '----' with a uniq id and set the origin to (id | (31-th bit)).316static inline void SetAllocaOrigin(void *a, uptr size, u32 *id_ptr, char *descr,317                                   uptr pc) {318  static const u32 dash = '-';319  static const u32 first_timer =320      dash + (dash << 8) + (dash << 16) + (dash << 24);321  u32 id = *id_ptr;322  if (id == 0 || id == first_timer) {323    u32 idx = atomic_fetch_add(&NumStackOriginDescrs, 1, memory_order_relaxed);324    CHECK_LT(idx, kNumStackOriginDescrs);325    StackOriginDescr[idx] = descr;326    StackOriginPC[idx] = pc;327    id = Origin::CreateStackOrigin(idx).raw_id();328    *id_ptr = id;329  }330  __msan_set_origin(a, size, id);331}332 333}  // namespace __msan334 335void __sanitizer::BufferedStackTrace::UnwindImpl(336    uptr pc, uptr bp, void *context, bool request_fast, u32 max_depth) {337  using namespace __msan;338  MsanThread *t = GetCurrentThread();339  if (!t || !StackTrace::WillUseFastUnwind(request_fast)) {340    // Block reports from our interceptors during _Unwind_Backtrace.341    UnwinderScope sym_scope;342    return Unwind(max_depth, pc, bp, context, t ? t->stack_top() : 0,343                  t ? t->stack_bottom() : 0, false);344  }345  if (StackTrace::WillUseFastUnwind(request_fast))346    Unwind(max_depth, pc, bp, nullptr, t->stack_top(), t->stack_bottom(), true);347  else348    Unwind(max_depth, pc, 0, context, 0, 0, false);349}350 351// Interface.352 353using namespace __msan;354 355// N.B. Only [shadow, shadow+size) is defined. shadow is *not* a pointer into356// an MSan shadow region.357static void print_shadow_value(void *shadow, u64 size) {358  Printf("Shadow value (%llu byte%s):", size, size == 1 ? "" : "s");359  for (unsigned int i = 0; i < size; i++) {360    if (i % 4 == 0)361      Printf(" ");362 363    unsigned char x = ((unsigned char *)shadow)[i];364    Printf("%x%x", x >> 4, x & 0xf);365  }366  Printf("\n");367  Printf(368      "Caveat: the shadow value does not necessarily directly correspond to a "369      "single user variable. The correspondence is stronger, but not always "370      "perfect, when origin tracking is enabled.\n");371  Printf("\n");372}373 374#define MSAN_MAYBE_WARNING(type, size)               \375  void __msan_maybe_warning_##size(type s, u32 o) {  \376    GET_CALLER_PC_BP;                                \377                                                     \378    if (UNLIKELY(s)) {                               \379      if (Verbosity() >= 1)                          \380        print_shadow_value((void *)(&s), sizeof(s)); \381      PrintWarningWithOrigin(pc, bp, o);             \382      if (__msan::flags()->halt_on_error) {          \383        Printf("Exiting\n");                         \384        Die();                                       \385      }                                              \386    }                                                \387  }388 389MSAN_MAYBE_WARNING(u8, 1)390MSAN_MAYBE_WARNING(u16, 2)391MSAN_MAYBE_WARNING(u32, 4)392MSAN_MAYBE_WARNING(u64, 8)393 394// N.B. Only [shadow, shadow+size) is defined. shadow is *not* a pointer into395// an MSan shadow region.396void __msan_maybe_warning_N(void *shadow, u64 size, u32 o) {397  GET_CALLER_PC_BP;398 399  bool allZero = true;400  for (unsigned int i = 0; i < size; i++) {401    if (((char *)shadow)[i]) {402      allZero = false;403      break;404    }405  }406 407  if (UNLIKELY(!allZero)) {408    if (Verbosity() >= 1)409      print_shadow_value(shadow, size);410    PrintWarningWithOrigin(pc, bp, o);411    if (__msan::flags()->halt_on_error) {412      Printf("Exiting\n");413      Die();414    }415  }416}417 418#define MSAN_MAYBE_STORE_ORIGIN(type, size)                       \419  void __msan_maybe_store_origin_##size(type s, void *p, u32 o) { \420    if (UNLIKELY(s)) {                                            \421      if (__msan_get_track_origins() > 1) {                       \422        GET_CALLER_PC_BP;                                         \423        GET_STORE_STACK_TRACE_PC_BP(pc, bp);                      \424        o = ChainOrigin(o, &stack);                               \425      }                                                           \426      *(u32 *)MEM_TO_ORIGIN((uptr)p & ~3UL) = o;                  \427    }                                                             \428  }429 430MSAN_MAYBE_STORE_ORIGIN(u8, 1)431MSAN_MAYBE_STORE_ORIGIN(u16, 2)432MSAN_MAYBE_STORE_ORIGIN(u32, 4)433MSAN_MAYBE_STORE_ORIGIN(u64, 8)434 435void __msan_warning() {436  GET_CALLER_PC_BP;437  PrintWarningWithOrigin(pc, bp, 0);438  if (__msan::flags()->halt_on_error) {439    if (__msan::flags()->print_stats)440      ReportStats();441    Printf("Exiting\n");442    Die();443  }444}445 446void __msan_warning_noreturn() {447  GET_CALLER_PC_BP;448  PrintWarningWithOrigin(pc, bp, 0);449  if (__msan::flags()->print_stats)450    ReportStats();451  Printf("Exiting\n");452  Die();453}454 455void __msan_warning_with_origin(u32 origin) {456  GET_CALLER_PC_BP;457  PrintWarningWithOrigin(pc, bp, origin);458  if (__msan::flags()->halt_on_error) {459    if (__msan::flags()->print_stats)460      ReportStats();461    Printf("Exiting\n");462    Die();463  }464}465 466void __msan_warning_with_origin_noreturn(u32 origin) {467  GET_CALLER_PC_BP;468  PrintWarningWithOrigin(pc, bp, origin);469  if (__msan::flags()->print_stats)470    ReportStats();471  Printf("Exiting\n");472  Die();473}474 475static void OnStackUnwind(const SignalContext &sig, const void *,476                          BufferedStackTrace *stack) {477  stack->Unwind(StackTrace::GetNextInstructionPc(sig.pc), sig.bp, sig.context,478                common_flags()->fast_unwind_on_fatal);479}480 481static void MsanOnDeadlySignal(int signo, void *siginfo, void *context) {482  HandleDeadlySignal(siginfo, context, GetTid(), &OnStackUnwind, nullptr);483}484 485static void CheckUnwind() {486  GET_FATAL_STACK_TRACE_PC_BP(StackTrace::GetCurrentPc(), GET_CURRENT_FRAME());487  stack.Print();488}489 490void __msan_init() {491  CHECK(!msan_init_is_running);492  if (msan_inited) return;493  msan_init_is_running = 1;494  SanitizerToolName = "MemorySanitizer";495 496  AvoidCVE_2016_2143();497 498  CacheBinaryName();499  InitializeFlags();500 501  // Install tool-specific callbacks in sanitizer_common.502  SetCheckUnwindCallback(CheckUnwind);503 504  __sanitizer_set_report_path(common_flags()->log_path);505 506  InitializePlatformEarly();507 508  InitializeInterceptors();509  InstallAtForkHandler();510  CheckASLR();511  InstallDeadlySignalHandlers(MsanOnDeadlySignal);512  InstallAtExitHandler(); // Needs __cxa_atexit interceptor.513 514  DisableCoreDumperIfNecessary();515  if (StackSizeIsUnlimited()) {516    VPrintf(1, "Unlimited stack, doing reexec\n");517    // A reasonably large stack size. It is bigger than the usual 8Mb, because,518    // well, the program could have been run with unlimited stack for a reason.519    SetStackSizeLimitInBytes(32 * 1024 * 1024);520    ReExec();521  }522 523  __msan_clear_on_return();524  if (__msan_get_track_origins())525    VPrintf(1, "msan_track_origins\n");526  if (!InitShadowWithReExec(__msan_get_track_origins())) {527    Printf("FATAL: MemorySanitizer can not mmap the shadow memory.\n");528    Printf("FATAL: Make sure to compile with -fPIE and to link with -pie.\n");529    Printf("FATAL: Disabling ASLR is known to cause this error.\n");530    Printf("FATAL: If running under GDB, try "531           "'set disable-randomization off'.\n");532    DumpProcessMap();533    Die();534  }535 536  Symbolizer::GetOrInit()->AddHooks(EnterSymbolizerOrUnwider,537                                    ExitSymbolizerOrUnwider);538 539  InitializeCoverage(common_flags()->coverage, common_flags()->coverage_dir);540 541  MsanTSDInit(MsanTSDDtor);542 543  MsanAllocatorInit();544 545  MsanThread *main_thread = MsanThread::Create(nullptr, nullptr);546  SetCurrentThread(main_thread);547  main_thread->Init();548 549#if MSAN_CONTAINS_UBSAN550  __ubsan::InitAsPlugin();551#endif552 553  VPrintf(1, "MemorySanitizer init done\n");554 555  msan_init_is_running = 0;556  msan_inited = 1;557}558 559void __msan_set_keep_going(int keep_going) {560  flags()->halt_on_error = !keep_going;561}562 563void __msan_set_expect_umr(int expect_umr) {564  if (expect_umr) {565    msan_expected_umr_found = 0;566  } else if (!msan_expected_umr_found) {567    GET_CALLER_PC_BP;568    GET_FATAL_STACK_TRACE_PC_BP(pc, bp);569    ReportExpectedUMRNotFound(&stack);570    Die();571  }572  msan_expect_umr = expect_umr;573}574 575void __msan_print_shadow(const void *x, uptr size) {576  if (!MEM_IS_APP(x)) {577    Printf("Not a valid application address: %p\n", x);578    return;579  }580 581  DescribeMemoryRange(x, size);582}583 584void __msan_dump_shadow(const void *x, uptr size) {585  if (!MEM_IS_APP(x)) {586    Printf("Not a valid application address: %p\n", x);587    return;588  }589 590  unsigned char *s = (unsigned char*)MEM_TO_SHADOW(x);591  Printf("%p[%p]  ", (void *)s, x);592  for (uptr i = 0; i < size; i++)593    Printf("%x%x ", s[i] >> 4, s[i] & 0xf);594  Printf("\n");595}596 597sptr __msan_test_shadow(const void *x, uptr size) {598  if (!MEM_IS_APP(x)) return -1;599  unsigned char *s = (unsigned char *)MEM_TO_SHADOW((uptr)x);600  if (__sanitizer::mem_is_zero((const char *)s, size))601    return -1;602  // Slow path: loop through again to find the location.603  for (uptr i = 0; i < size; ++i)604    if (s[i])605      return i;606  return -1;607}608 609void __msan_check_mem_is_initialized(const void *x, uptr size) {610  if (!__msan::flags()->report_umrs) return;611  sptr offset = __msan_test_shadow(x, size);612  if (offset < 0)613    return;614 615  GET_CALLER_PC_BP;616  ReportUMRInsideAddressRange(__func__, x, size, offset);617  __msan::PrintWarningWithOrigin(pc, bp,618                                 __msan_get_origin(((const char *)x) + offset));619  if (__msan::flags()->halt_on_error) {620    Printf("Exiting\n");621    Die();622  }623}624 625int __msan_set_poison_in_malloc(int do_poison) {626  int old = flags()->poison_in_malloc;627  flags()->poison_in_malloc = do_poison;628  return old;629}630 631int __msan_has_dynamic_component() { return false; }632 633NOINLINE634void __msan_clear_on_return() {635  __msan_param_tls[0] = 0;636}637 638void __msan_partial_poison(const void* data, void* shadow, uptr size) {639  internal_memcpy((void*)MEM_TO_SHADOW((uptr)data), shadow, size);640}641 642void __msan_load_unpoisoned(const void *src, uptr size, void *dst) {643  internal_memcpy(dst, src, size);644  __msan_unpoison(dst, size);645}646 647void __msan_set_origin(const void *a, uptr size, u32 origin) {648  if (__msan_get_track_origins()) SetOrigin(a, size, origin);649}650 651void __msan_set_alloca_origin(void *a, uptr size, char *descr) {652  SetAllocaOrigin(a, size, reinterpret_cast<u32 *>(descr), descr + 4,653                  GET_CALLER_PC());654}655 656void __msan_set_alloca_origin4(void *a, uptr size, char *descr, uptr pc) {657  // Intentionally ignore pc and use return address. This function is here for658  // compatibility, in case program is linked with library instrumented by659  // older clang.660  SetAllocaOrigin(a, size, reinterpret_cast<u32 *>(descr), descr + 4,661                  GET_CALLER_PC());662}663 664void __msan_set_alloca_origin_with_descr(void *a, uptr size, u32 *id_ptr,665                                         char *descr) {666  SetAllocaOrigin(a, size, id_ptr, descr, GET_CALLER_PC());667}668 669void __msan_set_alloca_origin_no_descr(void *a, uptr size, u32 *id_ptr) {670  SetAllocaOrigin(a, size, id_ptr, nullptr, GET_CALLER_PC());671}672 673u32 __msan_chain_origin(u32 id) {674  GET_CALLER_PC_BP;675  GET_STORE_STACK_TRACE_PC_BP(pc, bp);676  return ChainOrigin(id, &stack);677}678 679u32 __msan_get_origin(const void *a) {680  if (!__msan_get_track_origins()) return 0;681  uptr x = (uptr)a;682  uptr aligned = x & ~3ULL;683  uptr origin_ptr = MEM_TO_ORIGIN(aligned);684  return *(u32*)origin_ptr;685}686 687int __msan_origin_is_descendant_or_same(u32 this_id, u32 prev_id) {688  Origin o = Origin::FromRawId(this_id);689  while (o.raw_id() != prev_id && o.isChainedOrigin())690    o = o.getNextChainedOrigin(nullptr);691  return o.raw_id() == prev_id;692}693 694u32 __msan_get_umr_origin() {695  return __msan_origin_tls;696}697 698u16 __sanitizer_unaligned_load16(const uu16 *p) {699  internal_memcpy(&__msan_retval_tls[0], (void *)MEM_TO_SHADOW((uptr)p),700                  sizeof(uu16));701  if (__msan_get_track_origins())702    __msan_retval_origin_tls = GetOriginIfPoisoned((uptr)p, sizeof(*p));703  return *p;704}705u32 __sanitizer_unaligned_load32(const uu32 *p) {706  internal_memcpy(&__msan_retval_tls[0], (void *)MEM_TO_SHADOW((uptr)p),707                  sizeof(uu32));708  if (__msan_get_track_origins())709    __msan_retval_origin_tls = GetOriginIfPoisoned((uptr)p, sizeof(*p));710  return *p;711}712u64 __sanitizer_unaligned_load64(const uu64 *p) {713  internal_memcpy(&__msan_retval_tls[0], (void *)MEM_TO_SHADOW((uptr)p),714                  sizeof(uu64));715  if (__msan_get_track_origins())716    __msan_retval_origin_tls = GetOriginIfPoisoned((uptr)p, sizeof(*p));717  return *p;718}719void __sanitizer_unaligned_store16(uu16 *p, u16 x) {720  static_assert(sizeof(uu16) == sizeof(u16), "incompatible types");721  u16 s;722  internal_memcpy(&s, &__msan_param_tls[1], sizeof(uu16));723  internal_memcpy((void *)MEM_TO_SHADOW((uptr)p), &s, sizeof(uu16));724  if (s && __msan_get_track_origins())725    if (uu32 o = __msan_param_origin_tls[2])726      SetOriginIfPoisoned((uptr)p, (uptr)&s, sizeof(s), o);727  *p = x;728}729void __sanitizer_unaligned_store32(uu32 *p, u32 x) {730  static_assert(sizeof(uu32) == sizeof(u32), "incompatible types");731  u32 s;732  internal_memcpy(&s, &__msan_param_tls[1], sizeof(uu32));733  internal_memcpy((void *)MEM_TO_SHADOW((uptr)p), &s, sizeof(uu32));734  if (s && __msan_get_track_origins())735    if (uu32 o = __msan_param_origin_tls[2])736      SetOriginIfPoisoned((uptr)p, (uptr)&s, sizeof(s), o);737  *p = x;738}739void __sanitizer_unaligned_store64(uu64 *p, u64 x) {740  u64 s = __msan_param_tls[1];741  *(uu64 *)MEM_TO_SHADOW((uptr)p) = s;742  if (s && __msan_get_track_origins())743    if (uu32 o = __msan_param_origin_tls[2])744      SetOriginIfPoisoned((uptr)p, (uptr)&s, sizeof(s), o);745  *p = x;746}747 748void __msan_set_death_callback(void (*callback)(void)) {749  SetUserDieCallback(callback);750}751 752void __msan_start_switch_fiber(const void *bottom, uptr size) {753  MsanThread *t = GetCurrentThread();754  if (!t) {755    VReport(1, "__msan_start_switch_fiber called from unknown thread\n");756    return;757  }758  t->StartSwitchFiber((uptr)bottom, size);759}760 761void __msan_finish_switch_fiber(const void **bottom_old, uptr *size_old) {762  MsanThread *t = GetCurrentThread();763  if (!t) {764    VReport(1, "__msan_finish_switch_fiber called from unknown thread\n");765    return;766  }767  t->FinishSwitchFiber((uptr *)bottom_old, (uptr *)size_old);768 769  internal_memset(__msan_param_tls, 0, sizeof(__msan_param_tls));770  internal_memset(__msan_retval_tls, 0, sizeof(__msan_retval_tls));771  internal_memset(__msan_va_arg_tls, 0, sizeof(__msan_va_arg_tls));772 773  if (__msan_get_track_origins()) {774    internal_memset(__msan_param_origin_tls, 0,775                    sizeof(__msan_param_origin_tls));776    internal_memset(&__msan_retval_origin_tls, 0,777                    sizeof(__msan_retval_origin_tls));778    internal_memset(__msan_va_arg_origin_tls, 0,779                    sizeof(__msan_va_arg_origin_tls));780  }781}782 783SANITIZER_INTERFACE_WEAK_DEF(const char *, __msan_default_options, void) {784  return "";785}786 787extern "C" {788SANITIZER_INTERFACE_ATTRIBUTE789void __sanitizer_print_stack_trace() {790  GET_FATAL_STACK_TRACE_PC_BP(StackTrace::GetCurrentPc(), GET_CURRENT_FRAME());791  stack.Print();792}793} // extern "C"794