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 
26 namespace __asan {
27 
28 Flags asan_flags_dont_use_directly;  // use via flags().
29 
MaybeCallAsanDefaultOptions()30 static const char *MaybeCallAsanDefaultOptions() {
31   return (&__asan_default_options) ? __asan_default_options() : "";
32 }
33 
MaybeUseAsanDefaultOptionsCompileDefinition()34 static 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 
SetDefaults()45 void Flags::SetDefaults() {
46 #define ASAN_FLAG(Type, Name, DefaultValue, Description) Name = DefaultValue;
47 #include "asan_flags.inc"
48 #undef ASAN_FLAG
49 }
50 
RegisterAsanFlags(FlagParser * parser,Flags * f)51 static 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 
InitializeFlags()58 void 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   SetVerbosity(common_flags()->verbosity);
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 }
163 
164 }  // namespace __asan
165 
166 #if !SANITIZER_SUPPORTS_WEAK_HOOKS
167 extern "C" {
168 SANITIZER_INTERFACE_ATTRIBUTE SANITIZER_WEAK_ATTRIBUTE
__asan_default_options()169 const char* __asan_default_options() { return ""; }
170 }  // extern "C"
171 #endif
172