1//===-- asan_flags.cc -------------------------------------------*- C++ -*-===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// This file is a part of AddressSanitizer, an address sanity checker.
11//
12// ASan flag parsing logic.
13//===----------------------------------------------------------------------===//
14
15#include "asan_activation.h"
16#include "asan_flags.h"
17#include "asan_interface_internal.h"
18#include "asan_stack.h"
19#include "lsan/lsan_common.h"
20#include "sanitizer_common/sanitizer_common.h"
21#include "sanitizer_common/sanitizer_flags.h"
22#include "sanitizer_common/sanitizer_flag_parser.h"
23#include "ubsan/ubsan_flags.h"
24#include "ubsan/ubsan_platform.h"
25
26namespace __asan {
27
28Flags asan_flags_dont_use_directly;  // use via flags().
29
30static const char *MaybeCallAsanDefaultOptions() {
31  return (&__asan_default_options) ? __asan_default_options() : "";
32}
33
34static const char *MaybeUseAsanDefaultOptionsCompileDefinition() {
35#ifdef ASAN_DEFAULT_OPTIONS
36// Stringize the macro value.
37# define ASAN_STRINGIZE(x) #x
38# define ASAN_STRINGIZE_OPTIONS(options) ASAN_STRINGIZE(options)
39  return ASAN_STRINGIZE_OPTIONS(ASAN_DEFAULT_OPTIONS);
40#else
41  return "";
42#endif
43}
44
45void Flags::SetDefaults() {
46#define ASAN_FLAG(Type, Name, DefaultValue, Description) Name = DefaultValue;
47#include "asan_flags.inc"
48#undef ASAN_FLAG
49}
50
51static void RegisterAsanFlags(FlagParser *parser, Flags *f) {
52#define ASAN_FLAG(Type, Name, DefaultValue, Description) \
53  RegisterFlag(parser, #Name, Description, &f->Name);
54#include "asan_flags.inc"
55#undef ASAN_FLAG
56}
57
58void InitializeFlags() {
59  // Set the default values and prepare for parsing ASan and common flags.
60  SetCommonFlagsDefaults();
61  {
62    CommonFlags cf;
63    cf.CopyFrom(*common_flags());
64    cf.detect_leaks = CAN_SANITIZE_LEAKS;
65    cf.external_symbolizer_path = GetEnv("ASAN_SYMBOLIZER_PATH");
66    cf.malloc_context_size = kDefaultMallocContextSize;
67    cf.intercept_tls_get_addr = true;
68    cf.exitcode = 1;
69    OverrideCommonFlags(cf);
70  }
71  Flags *f = flags();
72  f->SetDefaults();
73
74  FlagParser asan_parser;
75  RegisterAsanFlags(&asan_parser, f);
76  RegisterCommonFlags(&asan_parser);
77
78  // Set the default values and prepare for parsing LSan and UBSan flags
79  // (which can also overwrite common flags).
80#if CAN_SANITIZE_LEAKS
81  __lsan::Flags *lf = __lsan::flags();
82  lf->SetDefaults();
83
84  FlagParser lsan_parser;
85  __lsan::RegisterLsanFlags(&lsan_parser, lf);
86  RegisterCommonFlags(&lsan_parser);
87#endif
88
89#if CAN_SANITIZE_UB
90  __ubsan::Flags *uf = __ubsan::flags();
91  uf->SetDefaults();
92
93  FlagParser ubsan_parser;
94  __ubsan::RegisterUbsanFlags(&ubsan_parser, uf);
95  RegisterCommonFlags(&ubsan_parser);
96#endif
97
98  // Override from ASan compile definition.
99  const char *asan_compile_def = MaybeUseAsanDefaultOptionsCompileDefinition();
100  asan_parser.ParseString(asan_compile_def);
101
102  // Override from user-specified string.
103  const char *asan_default_options = MaybeCallAsanDefaultOptions();
104  asan_parser.ParseString(asan_default_options);
105#if CAN_SANITIZE_UB
106  const char *ubsan_default_options = __ubsan::MaybeCallUbsanDefaultOptions();
107  ubsan_parser.ParseString(ubsan_default_options);
108#endif
109
110  // Override from command line.
111  asan_parser.ParseString(GetEnv("ASAN_OPTIONS"));
112#if CAN_SANITIZE_LEAKS
113  lsan_parser.ParseString(GetEnv("LSAN_OPTIONS"));
114#endif
115#if CAN_SANITIZE_UB
116  ubsan_parser.ParseString(GetEnv("UBSAN_OPTIONS"));
117#endif
118
119  InitializeCommonFlags();
120
121  // TODO(eugenis): dump all flags at verbosity>=2?
122  if (Verbosity()) ReportUnrecognizedFlags();
123
124  if (common_flags()->help) {
125    // TODO(samsonov): print all of the flags (ASan, LSan, common).
126    asan_parser.PrintFlagDescriptions();
127  }
128
129  // Flag validation:
130  if (!CAN_SANITIZE_LEAKS && common_flags()->detect_leaks) {
131    Report("%s: detect_leaks is not supported on this platform.\n",
132           SanitizerToolName);
133    Die();
134  }
135  // Make "strict_init_order" imply "check_initialization_order".
136  // TODO(samsonov): Use a single runtime flag for an init-order checker.
137  if (f->strict_init_order) {
138    f->check_initialization_order = true;
139  }
140  CHECK_LE((uptr)common_flags()->malloc_context_size, kStackTraceMax);
141  CHECK_LE(f->min_uar_stack_size_log, f->max_uar_stack_size_log);
142  CHECK_GE(f->redzone, 16);
143  CHECK_GE(f->max_redzone, f->redzone);
144  CHECK_LE(f->max_redzone, 2048);
145  CHECK(IsPowerOfTwo(f->redzone));
146  CHECK(IsPowerOfTwo(f->max_redzone));
147
148  // quarantine_size is deprecated but we still honor it.
149  // quarantine_size can not be used together with quarantine_size_mb.
150  if (f->quarantine_size >= 0 && f->quarantine_size_mb >= 0) {
151    Report("%s: please use either 'quarantine_size' (deprecated) or "
152           "quarantine_size_mb, but not both\n", SanitizerToolName);
153    Die();
154  }
155  if (f->quarantine_size >= 0)
156    f->quarantine_size_mb = f->quarantine_size >> 20;
157  if (f->quarantine_size_mb < 0) {
158    const int kDefaultQuarantineSizeMb =
159        (ASAN_LOW_MEMORY) ? 1UL << 6 : 1UL << 8;
160    f->quarantine_size_mb = kDefaultQuarantineSizeMb;
161  }
162  if (!f->replace_str && common_flags()->intercept_strlen) {
163    Report("WARNING: strlen interceptor is enabled even though replace_str=0. "
164           "Use intercept_strlen=0 to disable it.");
165  }
166  if (!f->replace_str && common_flags()->intercept_strchr) {
167    Report("WARNING: strchr* interceptors are enabled even though "
168           "replace_str=0. Use intercept_strchr=0 to disable them.");
169  }
170}
171
172}  // namespace __asan
173
174#if !SANITIZER_SUPPORTS_WEAK_HOOKS
175extern "C" {
176SANITIZER_INTERFACE_ATTRIBUTE SANITIZER_WEAK_ATTRIBUTE
177const char* __asan_default_options() { return ""; }
178}  // extern "C"
179#endif
180