1
    2
    3
    4
    5
    6
    7
    8
    9
   10
   11
   12
   13
   14
   15
   16
   17
   18
   19
   20
   21
   22
   23
   24
   25
   26
   27
   28
   29
   30
   31
   32
   33
   34
   35
   36
   37
   38
   39
   40
   41
   42
   43
   44
   45
   46
   47
   48
   49
   50
   51
   52
   53
   54
   55
   56
   57
   58
   59
   60
   61
   62
   63
   64
   65
   66
   67
   68
   69
   70
   71
   72
   73
   74
   75
   76
   77
   78
   79
   80
   81
   82
   83
   84
   85
   86
   87
   88
   89
   90
   91
   92
   93
   94
   95
   96
   97
   98
   99
  100
  101
  102
  103
  104
  105
  106
  107
  108
  109
  110
  111
  112
  113
  114
  115
  116
  117
  118
  119
  120
  121
  122
  123
  124
  125
  126
  127
  128
  129
  130
  131
  132
  133
  134
  135
  136
  137
  138
  139
  140
  141
  142
  143
  144
  145
  146
  147
  148
  149
  150
  151
  152
  153
  154
  155
  156
  157
  158
  159
  160
  161
  162
  163
  164
  165
  166
  167
  168
  169
  170
  171
  172
  173
  174
  175
  176
  177
  178
  179
  180
  181
  182
  183
  184
  185
  186
  187
  188
  189
  190
  191
  192
  193
  194
  195
  196
  197
  198
  199
  200
  201
  202
  203
  204
  205
  206
  207
  208
  209
  210
  211
  212
  213
  214
  215
  216
  217
  218
  219
  220
  221
  222
  223
  224
  225
  226
  227
  228
  229
  230
  231
  232
  233
  234
  235
  236
  237
  238
  239
  240
  241
  242
  243
  244
  245
  246
  247
  248
  249
  250
  251
  252
  253
  254
  255
  256
  257
  258
  259
  260
  261
  262
  263
  264
  265
  266
  267
  268
  269
  270
  271
  272
  273
  274
  275
  276
  277
  278
  279
  280
  281
  282
  283
  284
  285
  286
  287
  288
  289
  290
  291
  292
  293
  294
  295
  296
  297
  298
  299
  300
  301
  302
  303
  304
  305
  306
  307
  308
  309
  310
  311
  312
  313
  314
  315
  316
  317
  318
  319
  320
  321
  322
  323
  324
  325
  326
  327
  328
  329
  330
  331
  332
  333
  334
  335
  336
  337
  338
  339
  340
  341
  342
  343
  344
  345
  346
  347
  348
  349
  350
  351
  352
  353
  354
  355
  356
  357
  358
  359
  360
  361
  362
  363
  364
  365
  366
  367
  368
  369
  370
  371
  372
  373
  374
  375
  376
  377
  378
  379
  380
  381
  382
  383
  384
  385
  386
  387
  388
  389
  390
  391
  392
  393
  394
  395
  396
  397
  398
  399
  400
  401
  402
  403
  404
  405
  406
  407
  408
  409
  410
  411
  412
  413
  414
  415
  416
  417
  418
  419
  420
  421
  422
  423
  424
  425
  426
  427
  428
  429
  430
  431
  432
  433
  434
  435
  436
  437
  438
  439
  440
  441
  442
  443
  444
  445
  446
  447
  448
  449
  450
  451
  452
  453
  454
  455
  456
  457
  458
  459
  460
  461
  462
  463
  464
  465
  466

base / tools_sanity_unittest.cc [blame]

// Copyright 2012 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifdef UNSAFE_BUFFERS_BUILD
// TODO(crbug.com/40284755): Remove this and spanify to fix the errors.
#pragma allow_unsafe_buffers
#endif

// This file contains intentional memory errors, some of which may lead to
// crashes if the test is ran without special memory testing tools. We use these
// errors to verify the sanity of the tools.

#include <stddef.h>

#include "base/atomicops.h"
#include "base/cfi_buildflags.h"
#include "base/debug/asan_invalid_access.h"
#include "base/debug/profiler.h"
#include "base/logging.h"
#include "base/memory/raw_ptr.h"
#include "base/notreached.h"
#include "base/sanitizer_buildflags.h"
#include "base/threading/thread.h"
#include "build/build_config.h"
#include "testing/gtest/include/gtest/gtest.h"
#include "third_party/abseil-cpp/absl/base/dynamic_annotations.h"

#if BUILDFLAG(IS_WIN)
#include <windows.h>
#else
#include <dlfcn.h>
#endif

namespace base {

namespace {

const base::subtle::Atomic32 kMagicValue = 42;

// Helper for memory accesses that can potentially corrupt memory or cause a
// crash during a native run.
#if defined(ADDRESS_SANITIZER)
#define HARMFUL_ACCESS(action, error_regexp) \
  EXPECT_DEATH_IF_SUPPORTED(action, error_regexp)
#elif BUILDFLAG(IS_HWASAN)
#define HARMFUL_ACCESS(action, error_regexp) \
  EXPECT_DEATH(action, "tag-mismatch")
#else
#define HARMFUL_ACCESS(action, error_regexp)
#define HARMFUL_ACCESS_IS_NOOP
#endif

void DoReadUninitializedValue(volatile char *ptr) {
  // Comparison with 64 is to prevent clang from optimizing away the
  // jump -- valgrind only catches jumps and conditional moves, but clang uses
  // the borrow flag if the condition is just `*ptr == '\0'`.  We no longer
  // support valgrind, but this constant should be fine to keep as-is.
  if (*ptr == 64) {
    VLOG(1) << "Uninit condition is true";
  } else {
    VLOG(1) << "Uninit condition is false";
  }
}

void ReadUninitializedValue(volatile char *ptr) {
#if defined(MEMORY_SANITIZER)
  EXPECT_DEATH(DoReadUninitializedValue(ptr),
               "use-of-uninitialized-value");
#else
  DoReadUninitializedValue(ptr);
#endif
}

#ifndef HARMFUL_ACCESS_IS_NOOP
void ReadValueOutOfArrayBoundsLeft(char *ptr) {
  char c = ptr[-2];
  VLOG(1) << "Reading a byte out of bounds: " << c;
}

void ReadValueOutOfArrayBoundsRight(char *ptr, size_t size) {
  char c = ptr[size + 1];
  VLOG(1) << "Reading a byte out of bounds: " << c;
}

void WriteValueOutOfArrayBoundsLeft(char *ptr) {
  ptr[-1] = kMagicValue;
}

void WriteValueOutOfArrayBoundsRight(char *ptr, size_t size) {
  ptr[size] = kMagicValue;
}
#endif  // HARMFUL_ACCESS_IS_NOOP

void MakeSomeErrors(char *ptr, size_t size) {
  ReadUninitializedValue(ptr);

  HARMFUL_ACCESS(ReadValueOutOfArrayBoundsLeft(ptr), "2 bytes before");
  HARMFUL_ACCESS(ReadValueOutOfArrayBoundsRight(ptr, size), "1 bytes after");
  HARMFUL_ACCESS(WriteValueOutOfArrayBoundsLeft(ptr), "1 bytes before");
  HARMFUL_ACCESS(WriteValueOutOfArrayBoundsRight(ptr, size), "0 bytes after");
}

}  // namespace

#if defined(ADDRESS_SANITIZER) || defined(LEAK_SANITIZER) ||  \
    defined(MEMORY_SANITIZER) || defined(THREAD_SANITIZER) || \
    defined(UNDEFINED_SANITIZER)
// build/sanitizers/sanitizer_options.cc defines symbols like
// __asan_default_options which the sanitizer runtime calls if they exist
// in the executable. If they don't, the sanitizer runtime silently uses an
// internal default value instead. The build puts the symbol
// _sanitizer_options_link_helper (which the sanitizer runtime doesn't know
// about, it's a chrome thing) in that file and then tells the linker that
// that symbol must exist. This causes sanitizer_options.cc to be part of
// our binaries, which in turn makes sure our __asan_default_options are used.
// We had problems with __asan_default_options not being used, so this test
// verifies that _sanitizer_options_link_helper actually makes it into our
// binaries.
#if BUILDFLAG(IS_ANDROID) || BUILDFLAG(IS_WIN)
// TODO(crbug.com/40224191): Sanitizer options are currently broken
// on Android.
// TODO(crbug.com/40223949): __asan_default_options should be used
// on Windows too, but currently isn't.
#define MAYBE_LinksSanitizerOptions DISABLED_LinksSanitizerOptions
#else
#define MAYBE_LinksSanitizerOptions LinksSanitizerOptions
#endif
TEST(ToolsSanityTest, MAYBE_LinksSanitizerOptions) {
  constexpr char kSym[] = "_sanitizer_options_link_helper";
#if BUILDFLAG(IS_WIN)
  auto sym = GetProcAddress(GetModuleHandle(nullptr), kSym);
#else
  void* sym = dlsym(RTLD_DEFAULT, kSym);
#endif
  EXPECT_TRUE(sym != nullptr);
}
#endif  // sanitizers

// A memory leak detector should report an error in this test.
TEST(ToolsSanityTest, MemoryLeak) {
  // Without the |volatile|, clang optimizes away the next two lines.
  int* volatile leak = new int[256];  // Leak some memory intentionally.
  leak[4] = 1;  // Make sure the allocated memory is used.
}

TEST(ToolsSanityTest, AccessesToNewMemory) {
  char* foo = new char[16];
  MakeSomeErrors(foo, 16);
  delete [] foo;
  // Use after delete.
  HARMFUL_ACCESS(foo[5] = 0, "heap-use-after-free");
}

TEST(ToolsSanityTest, AccessesToMallocMemory) {
  char* foo = reinterpret_cast<char*>(malloc(16));
  MakeSomeErrors(foo, 16);
  free(foo);
  // Use after free.
  HARMFUL_ACCESS(foo[5] = 0, "heap-use-after-free");
}

TEST(ToolsSanityTest, AccessesToStack) {
  char foo[16];

  ReadUninitializedValue(foo);
  HARMFUL_ACCESS(ReadValueOutOfArrayBoundsLeft(foo),
                 "underflows this variable");
  HARMFUL_ACCESS(ReadValueOutOfArrayBoundsRight(foo, 16),
                 "overflows this variable");
  HARMFUL_ACCESS(WriteValueOutOfArrayBoundsLeft(foo),
                 "underflows this variable");
  HARMFUL_ACCESS(WriteValueOutOfArrayBoundsRight(foo, 16),
                 "overflows this variable");
}

#if defined(ADDRESS_SANITIZER)

// alloc_dealloc_mismatch defaults to
// !SANITIZER_MAC && !SANITIZER_WINDOWS && !SANITIZER_ANDROID,
// in the sanitizer runtime upstream.
#if BUILDFLAG(IS_ANDROID) || BUILDFLAG(IS_MAC) || BUILDFLAG(IS_WIN) || \
    BUILDFLAG(IS_FUCHSIA)
#define MAYBE_SingleElementDeletedWithBraces \
    DISABLED_SingleElementDeletedWithBraces
#define MAYBE_ArrayDeletedWithoutBraces DISABLED_ArrayDeletedWithoutBraces
#else
#define MAYBE_ArrayDeletedWithoutBraces ArrayDeletedWithoutBraces
#define MAYBE_SingleElementDeletedWithBraces SingleElementDeletedWithBraces
#endif  // defined(ADDRESS_SANITIZER)

static int* allocateArray() {
  // Clang warns about the mismatched new[]/delete if they occur in the same
  // function.
  return new int[10];
}

// This test may corrupt memory if not compiled with AddressSanitizer.
TEST(ToolsSanityTest, MAYBE_ArrayDeletedWithoutBraces) {
  // Without the |volatile|, clang optimizes away the next two lines.
  int* volatile foo = allocateArray();
  HARMFUL_ACCESS(delete foo, "alloc-dealloc-mismatch");
  // Under ASan the crash happens in the process spawned by HARMFUL_ACCESS,
  // need to free the memory in the parent.
  delete [] foo;
}

static int* allocateScalar() {
  // Clang warns about the mismatched new/delete[] if they occur in the same
  // function.
  return new int;
}

// This test may corrupt memory if not compiled with AddressSanitizer.
TEST(ToolsSanityTest, MAYBE_SingleElementDeletedWithBraces) {
  // Without the |volatile|, clang optimizes away the next two lines.
  int* volatile foo = allocateScalar();
  (void) foo;
  HARMFUL_ACCESS(delete [] foo, "alloc-dealloc-mismatch");
  // Under ASan the crash happens in the process spawned by HARMFUL_ACCESS,
  // need to free the memory in the parent.
  delete foo;
}
#endif

TEST(ToolsSanityTest, DISABLED_AddressSanitizerNullDerefCrashTest) {
  // Intentionally crash to make sure AddressSanitizer is running.
  // This test should not be ran on bots.
  int* volatile zero = NULL;
  *zero = 0;
}

TEST(ToolsSanityTest, DISABLED_AddressSanitizerLocalOOBCrashTest) {
  // Intentionally crash to make sure AddressSanitizer is instrumenting
  // the local variables.
  // This test should not be ran on bots.
  int array[5];
  // Work around the OOB warning reported by Clang.
  int* volatile access = &array[5];
  *access = 43;
}

namespace {
int g_asan_test_global_array[10];
}  // namespace

TEST(ToolsSanityTest, DISABLED_AddressSanitizerGlobalOOBCrashTest) {
  // Intentionally crash to make sure AddressSanitizer is instrumenting
  // the global variables.
  // This test should not be ran on bots.

  // Work around the OOB warning reported by Clang.
  int* volatile access = g_asan_test_global_array - 1;
  *access = 43;
}

#ifndef HARMFUL_ACCESS_IS_NOOP
TEST(ToolsSanityTest, AsanHeapOverflow) {
  HARMFUL_ACCESS(debug::AsanHeapOverflow(), "after");
}

TEST(ToolsSanityTest, AsanHeapUnderflow) {
  HARMFUL_ACCESS(debug::AsanHeapUnderflow(), "before");
}

TEST(ToolsSanityTest, AsanHeapUseAfterFree) {
  HARMFUL_ACCESS(debug::AsanHeapUseAfterFree(), "heap-use-after-free");
}

#if BUILDFLAG(IS_WIN)
// The ASAN runtime doesn't detect heap corruption, this needs fixing before
// ASAN builds can ship to the wild. See https://crbug.com/818747.
TEST(ToolsSanityTest, DISABLED_AsanCorruptHeapBlock) {
  HARMFUL_ACCESS(debug::AsanCorruptHeapBlock(), "");
}

TEST(ToolsSanityTest, DISABLED_AsanCorruptHeap) {
  // This test will kill the process by raising an exception, there's no
  // particular string to look for in the stack trace.
  EXPECT_DEATH(debug::AsanCorruptHeap(), "");
}
#endif  // BUILDFLAG(IS_WIN)
#endif  // !HARMFUL_ACCESS_IS_NOOP

namespace {

// We use caps here just to ensure that the method name doesn't interfere with
// the wildcarded suppressions.
class TOOLS_SANITY_TEST_CONCURRENT_THREAD : public PlatformThread::Delegate {
 public:
  explicit TOOLS_SANITY_TEST_CONCURRENT_THREAD(bool *value) : value_(value) {}
  ~TOOLS_SANITY_TEST_CONCURRENT_THREAD() override = default;
  void ThreadMain() override {
    *value_ = true;

    // Sleep for a few milliseconds so the two threads are more likely to live
    // simultaneously. Otherwise we may miss the report due to mutex
    // lock/unlock's inside thread creation code in pure-happens-before mode...
    PlatformThread::Sleep(Milliseconds(100));
  }
 private:
  raw_ptr<bool> value_;
};

class ReleaseStoreThread : public PlatformThread::Delegate {
 public:
  explicit ReleaseStoreThread(base::subtle::Atomic32 *value) : value_(value) {}
  ~ReleaseStoreThread() override = default;
  void ThreadMain() override {
    base::subtle::Release_Store(value_, kMagicValue);

    // Sleep for a few milliseconds so the two threads are more likely to live
    // simultaneously. Otherwise we may miss the report due to mutex
    // lock/unlock's inside thread creation code in pure-happens-before mode...
    PlatformThread::Sleep(Milliseconds(100));
  }
 private:
  raw_ptr<base::subtle::Atomic32> value_;
};

class AcquireLoadThread : public PlatformThread::Delegate {
 public:
  explicit AcquireLoadThread(base::subtle::Atomic32 *value) : value_(value) {}
  ~AcquireLoadThread() override = default;
  void ThreadMain() override {
    // Wait for the other thread to make Release_Store
    PlatformThread::Sleep(Milliseconds(100));
    base::subtle::Acquire_Load(value_);
  }
 private:
  raw_ptr<base::subtle::Atomic32> value_;
};

void RunInParallel(PlatformThread::Delegate *d1, PlatformThread::Delegate *d2) {
  PlatformThreadHandle a;
  PlatformThreadHandle b;
  PlatformThread::Create(0, d1, &a);
  PlatformThread::Create(0, d2, &b);
  PlatformThread::Join(a);
  PlatformThread::Join(b);
}

#if defined(THREAD_SANITIZER)
void DataRace() {
  bool *shared = new bool(false);
  TOOLS_SANITY_TEST_CONCURRENT_THREAD thread1(shared), thread2(shared);
  RunInParallel(&thread1, &thread2);
  EXPECT_TRUE(*shared);
  delete shared;
  // We're in a death test - crash.
  NOTREACHED();
}
#endif

}  // namespace

#if defined(THREAD_SANITIZER)
// A data race detector should report an error in this test.
TEST(ToolsSanityTest, DataRace) {
  // The suppression regexp must match that in base/debug/tsan_suppressions.cc.
  EXPECT_DEATH(DataRace(), "1 race:base/tools_sanity_unittest.cc");
}
#endif

TEST(ToolsSanityTest, AnnotateBenignRace) {
  bool shared = false;
  ABSL_ANNOTATE_BENIGN_RACE(
      &shared, "Intentional race - make sure doesn't show up");
  TOOLS_SANITY_TEST_CONCURRENT_THREAD thread1(&shared), thread2(&shared);
  RunInParallel(&thread1, &thread2);
  EXPECT_TRUE(shared);
}

TEST(ToolsSanityTest, AtomicsAreIgnored) {
  base::subtle::Atomic32 shared = 0;
  ReleaseStoreThread thread1(&shared);
  AcquireLoadThread thread2(&shared);
  RunInParallel(&thread1, &thread2);
  EXPECT_EQ(kMagicValue, shared);
}

#if BUILDFLAG(CFI_ENFORCEMENT_TRAP)
#if BUILDFLAG(IS_WIN)
#define CFI_ERROR_MSG "EXCEPTION_ILLEGAL_INSTRUCTION"
#elif BUILDFLAG(IS_ANDROID)
// TODO(pcc): Produce proper stack dumps on Android and test for the correct
// si_code here.
#define CFI_ERROR_MSG "^$"
#else
#define CFI_ERROR_MSG "ILL_ILLOPN"
#endif
#elif BUILDFLAG(CFI_ENFORCEMENT_DIAGNOSTIC)
#define CFI_ERROR_MSG "runtime error: control flow integrity check"
#endif  // BUILDFLAG(CFI_ENFORCEMENT_TRAP || CFI_ENFORCEMENT_DIAGNOSTIC)

#if defined(CFI_ERROR_MSG)
class A {
 public:
  A(): n_(0) {}
  virtual void f() { n_++; }
 protected:
  int n_;
};

class B: public A {
 public:
  void f() override { n_--; }
};

class C: public B {
 public:
  void f() override { n_ += 2; }
};

NOINLINE void KillVptrAndCall(A *obj) {
  *reinterpret_cast<void **>(obj) = 0;
  obj->f();
}

TEST(ToolsSanityTest, BadVirtualCallNull) {
  A a;
  B b;
  EXPECT_DEATH({ KillVptrAndCall(&a); KillVptrAndCall(&b); }, CFI_ERROR_MSG);
}

NOINLINE void OverwriteVptrAndCall(B *obj, A *vptr) {
  *reinterpret_cast<void **>(obj) = *reinterpret_cast<void **>(vptr);
  obj->f();
}

TEST(ToolsSanityTest, BadVirtualCallWrongType) {
  A a;
  B b;
  C c;
  EXPECT_DEATH({ OverwriteVptrAndCall(&b, &a); OverwriteVptrAndCall(&b, &c); },
               CFI_ERROR_MSG);
}

// TODO(pcc): remove CFI_CAST_CHECK, see https://crbug.com/626794.
#if BUILDFLAG(CFI_CAST_CHECK)
TEST(ToolsSanityTest, BadDerivedCast) {
  A a;
  EXPECT_DEATH((void)(B*)&a, CFI_ERROR_MSG);
}

TEST(ToolsSanityTest, BadUnrelatedCast) {
  class A {
    virtual void f() {}
  };

  class B {
    virtual void f() {}
  };

  A a;
  EXPECT_DEATH((void)(B*)&a, CFI_ERROR_MSG);
}
#endif  // BUILDFLAG(CFI_CAST_CHECK)

#endif  // CFI_ERROR_MSG

#undef CFI_ERROR_MSG
#undef HARMFUL_ACCESS
#undef HARMFUL_ACCESS_IS_NOOP

}  // namespace base