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 return SANITIZER_STRINGIFY(ASAN_DEFAULT_OPTIONS); 37#else 38 return ""; 39#endif 40} 41 42void Flags::SetDefaults() { 43#define ASAN_FLAG(Type, Name, DefaultValue, Description) Name = DefaultValue; 44#include "asan_flags.inc" 45#undef ASAN_FLAG 46} 47 48static void RegisterAsanFlags(FlagParser *parser, Flags *f) { 49#define ASAN_FLAG(Type, Name, DefaultValue, Description) \ 50 RegisterFlag(parser, #Name, Description, &f->Name); 51#include "asan_flags.inc" 52#undef ASAN_FLAG 53} 54 55void InitializeFlags() { 56 // Set the default values and prepare for parsing ASan and common flags. 57 SetCommonFlagsDefaults(); 58 { 59 CommonFlags cf; 60 cf.CopyFrom(*common_flags()); 61 cf.detect_leaks = cf.detect_leaks && CAN_SANITIZE_LEAKS; 62 cf.external_symbolizer_path = GetEnv("ASAN_SYMBOLIZER_PATH"); 63 cf.malloc_context_size = kDefaultMallocContextSize; 64 cf.intercept_tls_get_addr = true; 65 cf.exitcode = 1; 66 OverrideCommonFlags(cf); 67 } 68 Flags *f = flags(); 69 f->SetDefaults(); 70 71 FlagParser asan_parser; 72 RegisterAsanFlags(&asan_parser, f); 73 RegisterCommonFlags(&asan_parser); 74 75 // Set the default values and prepare for parsing LSan and UBSan flags 76 // (which can also overwrite common flags). 77#if CAN_SANITIZE_LEAKS 78 __lsan::Flags *lf = __lsan::flags(); 79 lf->SetDefaults(); 80 81 FlagParser lsan_parser; 82 __lsan::RegisterLsanFlags(&lsan_parser, lf); 83 RegisterCommonFlags(&lsan_parser); 84#endif 85 86#if CAN_SANITIZE_UB 87 __ubsan::Flags *uf = __ubsan::flags(); 88 uf->SetDefaults(); 89 90 FlagParser ubsan_parser; 91 __ubsan::RegisterUbsanFlags(&ubsan_parser, uf); 92 RegisterCommonFlags(&ubsan_parser); 93#endif 94 95 if (SANITIZER_MAC) { 96 // Support macOS MallocScribble and MallocPreScribble: 97 // <https://developer.apple.com/library/content/documentation/Performance/ 98 // Conceptual/ManagingMemory/Articles/MallocDebug.html> 99 if (GetEnv("MallocScribble")) { 100 f->max_free_fill_size = 0x1000; 101 } 102 if (GetEnv("MallocPreScribble")) { 103 f->malloc_fill_byte = 0xaa; 104 } 105 } 106 107 // Override from ASan compile definition. 108 const char *asan_compile_def = MaybeUseAsanDefaultOptionsCompileDefinition(); 109 asan_parser.ParseString(asan_compile_def); 110 111 // Override from user-specified string. 112 const char *asan_default_options = MaybeCallAsanDefaultOptions(); 113 asan_parser.ParseString(asan_default_options); 114#if CAN_SANITIZE_UB 115 const char *ubsan_default_options = __ubsan::MaybeCallUbsanDefaultOptions(); 116 ubsan_parser.ParseString(ubsan_default_options); 117#endif 118#if CAN_SANITIZE_LEAKS 119 const char *lsan_default_options = __lsan::MaybeCallLsanDefaultOptions(); 120 lsan_parser.ParseString(lsan_default_options); 121#endif 122 123 // Override from command line. 124 asan_parser.ParseString(GetEnv("ASAN_OPTIONS")); 125#if CAN_SANITIZE_LEAKS 126 lsan_parser.ParseString(GetEnv("LSAN_OPTIONS")); 127#endif 128#if CAN_SANITIZE_UB 129 ubsan_parser.ParseString(GetEnv("UBSAN_OPTIONS")); 130#endif 131 132 InitializeCommonFlags(); 133 134 // TODO(eugenis): dump all flags at verbosity>=2? 135 if (Verbosity()) ReportUnrecognizedFlags(); 136 137 if (common_flags()->help) { 138 // TODO(samsonov): print all of the flags (ASan, LSan, common). 139 asan_parser.PrintFlagDescriptions(); 140 } 141 142 // Flag validation: 143 if (!CAN_SANITIZE_LEAKS && common_flags()->detect_leaks) { 144 Report("%s: detect_leaks is not supported on this platform.\n", 145 SanitizerToolName); 146 Die(); 147 } 148 // Ensure that redzone is at least SHADOW_GRANULARITY. 149 if (f->redzone < (int)SHADOW_GRANULARITY) 150 f->redzone = SHADOW_GRANULARITY; 151 // Make "strict_init_order" imply "check_initialization_order". 152 // TODO(samsonov): Use a single runtime flag for an init-order checker. 153 if (f->strict_init_order) { 154 f->check_initialization_order = true; 155 } 156 CHECK_LE((uptr)common_flags()->malloc_context_size, kStackTraceMax); 157 CHECK_LE(f->min_uar_stack_size_log, f->max_uar_stack_size_log); 158 CHECK_GE(f->redzone, 16); 159 CHECK_GE(f->max_redzone, f->redzone); 160 CHECK_LE(f->max_redzone, 2048); 161 CHECK(IsPowerOfTwo(f->redzone)); 162 CHECK(IsPowerOfTwo(f->max_redzone)); 163 if (SANITIZER_RTEMS) { 164 CHECK(!f->unmap_shadow_on_exit); 165 CHECK(!f->protect_shadow_gap); 166 } 167 168 // quarantine_size is deprecated but we still honor it. 169 // quarantine_size can not be used together with quarantine_size_mb. 170 if (f->quarantine_size >= 0 && f->quarantine_size_mb >= 0) { 171 Report("%s: please use either 'quarantine_size' (deprecated) or " 172 "quarantine_size_mb, but not both\n", SanitizerToolName); 173 Die(); 174 } 175 if (f->quarantine_size >= 0) 176 f->quarantine_size_mb = f->quarantine_size >> 20; 177 if (f->quarantine_size_mb < 0) { 178 const int kDefaultQuarantineSizeMb = 179 (ASAN_LOW_MEMORY) ? 1UL << 4 : 1UL << 8; 180 f->quarantine_size_mb = kDefaultQuarantineSizeMb; 181 } 182 if (f->thread_local_quarantine_size_kb < 0) { 183 const u32 kDefaultThreadLocalQuarantineSizeKb = 184 // It is not advised to go lower than 64Kb, otherwise quarantine batches 185 // pushed from thread local quarantine to global one will create too 186 // much overhead. One quarantine batch size is 8Kb and it holds up to 187 // 1021 chunk, which amounts to 1/8 memory overhead per batch when 188 // thread local quarantine is set to 64Kb. 189 (ASAN_LOW_MEMORY) ? 1 << 6 : FIRST_32_SECOND_64(1 << 8, 1 << 10); 190 f->thread_local_quarantine_size_kb = kDefaultThreadLocalQuarantineSizeKb; 191 } 192 if (f->thread_local_quarantine_size_kb == 0 && f->quarantine_size_mb > 0) { 193 Report("%s: thread_local_quarantine_size_kb can be set to 0 only when " 194 "quarantine_size_mb is set to 0\n", SanitizerToolName); 195 Die(); 196 } 197 if (!f->replace_str && common_flags()->intercept_strlen) { 198 Report("WARNING: strlen interceptor is enabled even though replace_str=0. " 199 "Use intercept_strlen=0 to disable it."); 200 } 201 if (!f->replace_str && common_flags()->intercept_strchr) { 202 Report("WARNING: strchr* interceptors are enabled even though " 203 "replace_str=0. Use intercept_strchr=0 to disable them."); 204 } 205 if (!f->replace_str && common_flags()->intercept_strndup) { 206 Report("WARNING: strndup* interceptors are enabled even though " 207 "replace_str=0. Use intercept_strndup=0 to disable them."); 208 } 209} 210 211} // namespace __asan 212 213SANITIZER_INTERFACE_WEAK_DEF(const char*, __asan_default_options, void) { 214 return ""; 215} 216