libsanitizer/lsan/lsan_common.h

   1 //=-- lsan_common.h -------------------------------------------------------===//
   2 //
   3 // This file is distributed under the University of Illinois Open Source
   4 // License. See LICENSE.TXT for details.
   5 //
   6 //===----------------------------------------------------------------------===//
   7 //
   8 // This file is a part of LeakSanitizer.
   9 // Private LSan header.
  10 //
  11 //===----------------------------------------------------------------------===//
  12
  13 #ifndef LSAN_COMMON_H
  14 #define LSAN_COMMON_H
  15
  16 #include "sanitizer_common/sanitizer_allocator.h"
  17 #include "sanitizer_common/sanitizer_common.h"
  18 #include "sanitizer_common/sanitizer_internal_defs.h"
  19 #include "sanitizer_common/sanitizer_platform.h"
  20 #include "sanitizer_common/sanitizer_stoptheworld.h"
  21 #include "sanitizer_common/sanitizer_symbolizer.h"
  22
  23 // LeakSanitizer relies on some Glibc's internals (e.g. TLS machinery) thus
  24 // supported for Linux only. Also, LSan doesn't like 32 bit architectures
  25 // because of "small" (4 bytes) pointer size that leads to high false negative
  26 // ratio on large leaks. But we still want to have it for some 32 bit arches
  27 // (e.g. x86), see https://github.com/google/sanitizers/issues/403.
  28 // To enable LeakSanitizer on new architecture, one need to implement
  29 // internal_clone function as well as (probably) adjust TLS machinery for
  30 // new architecture inside sanitizer library.
  31 #if (SANITIZER_LINUX && !SANITIZER_ANDROID || SANITIZER_MAC) && \
  32     (SANITIZER_WORDSIZE == 64) &&                               \
  33     (defined(__x86_64__) || defined(__mips64) || defined(__aarch64__) || \
  34      defined(__powerpc64__))
  35 #define CAN_SANITIZE_LEAKS 1
  36 #elif defined(__i386__) && \
  37     (SANITIZER_LINUX && !SANITIZER_ANDROID || SANITIZER_MAC)
  38 #define CAN_SANITIZE_LEAKS 1
  39 #elif defined(__arm__) && \
  40     SANITIZER_LINUX && !SANITIZER_ANDROID
  41 #define CAN_SANITIZE_LEAKS 1
  42 #else
  43 #define CAN_SANITIZE_LEAKS 0
  44 #endif
  45
  46 namespace __sanitizer {
  47 class FlagParser;
  48 struct DTLS;
  49 }
  50
  51 namespace __lsan {
  52
  53 // Chunk tags.
  54 enum ChunkTag {
  55   kDirectlyLeaked = 0,  // default
  56   kIndirectlyLeaked = 1,
  57   kReachable = 2,
  58   kIgnored = 3
  59 };
  60
  61 const u32 kInvalidTid = (u32) -1;
  62
  63 struct Flags {
  64 #define LSAN_FLAG(Type, Name, DefaultValue, Description) Type Name;
  65 #include "lsan_flags.inc"
  66 #undef LSAN_FLAG
  67
  68   void SetDefaults();
  69   uptr pointer_alignment() const {
  70     return use_unaligned ? 1 : sizeof(uptr);
  71   }
  72 };
  73
  74 extern Flags lsan_flags;
  75 inline Flags *flags() { return &lsan_flags; }
  76 void RegisterLsanFlags(FlagParser *parser, Flags *f);
  77
  78 struct Leak {
  79   u32 id;
  80   uptr hit_count;
  81   uptr total_size;
  82   u32 stack_trace_id;
  83   bool is_directly_leaked;
  84   bool is_suppressed;
  85 };
  86
  87 struct LeakedObject {
  88   u32 leak_id;
  89   uptr addr;
  90   uptr size;
  91 };
  92
  93 // Aggregates leaks by stack trace prefix.
  94 class LeakReport {
  95  public:
  96   LeakReport() : next_id_(0), leaks_(1), leaked_objects_(1) {}
  97   void AddLeakedChunk(uptr chunk, u32 stack_trace_id, uptr leaked_size,
  98                       ChunkTag tag);
  99   void ReportTopLeaks(uptr max_leaks);
 100   void PrintSummary();
 101   void ApplySuppressions();
 102   uptr UnsuppressedLeakCount();
 103
 104
 105  private:
 106   void PrintReportForLeak(uptr index);
 107   void PrintLeakedObjectsForLeak(uptr index);
 108
 109   u32 next_id_;
 110   InternalMmapVector<Leak> leaks_;
 111   InternalMmapVector<LeakedObject> leaked_objects_;
 112 };
 113
 114 typedef InternalMmapVector<uptr> Frontier;
 115
 116 // Platform-specific functions.
 117 void InitializePlatformSpecificModules();
 118 void ProcessGlobalRegions(Frontier *frontier);
 119 void ProcessPlatformSpecificAllocations(Frontier *frontier);
 120
 121 struct RootRegion {
 122   uptr begin;
 123   uptr size;
 124 };
 125
 126 InternalMmapVector<RootRegion> const *GetRootRegions();
 127 void ScanRootRegion(Frontier *frontier, RootRegion const &region,
 128                     uptr region_begin, uptr region_end, bool is_readable);
 129 // Run stoptheworld while holding any platform-specific locks.
 130 void DoStopTheWorld(StopTheWorldCallback callback, void* argument);
 131
 132 void ScanRangeForPointers(uptr begin, uptr end,
 133                           Frontier *frontier,
 134                           const char *region_type, ChunkTag tag);
 135 void ScanGlobalRange(uptr begin, uptr end, Frontier *frontier);
 136
 137 enum IgnoreObjectResult {
 138   kIgnoreObjectSuccess,
 139   kIgnoreObjectAlreadyIgnored,
 140   kIgnoreObjectInvalid
 141 };
 142
 143 // Functions called from the parent tool.
 144 const char *MaybeCallLsanDefaultOptions();
 145 void InitCommonLsan();
 146 void DoLeakCheck();
 147 void DoRecoverableLeakCheckVoid();
 148 void DisableCounterUnderflow();
 149 bool DisabledInThisThread();
 150
 151 // Used to implement __lsan::ScopedDisabler.
 152 void DisableInThisThread();
 153 void EnableInThisThread();
 154 // Can be used to ignore memory allocated by an intercepted
 155 // function.
 156 struct ScopedInterceptorDisabler {
 157   ScopedInterceptorDisabler() { DisableInThisThread(); }
 158   ~ScopedInterceptorDisabler() { EnableInThisThread(); }
 159 };
 160
 161 // According to Itanium C++ ABI array cookie is a one word containing
 162 // size of allocated array.
 163 static inline bool IsItaniumABIArrayCookie(uptr chunk_beg, uptr chunk_size,
 164                                            uptr addr) {
 165   return chunk_size == sizeof(uptr) && chunk_beg + chunk_size == addr &&
 166          *reinterpret_cast<uptr *>(chunk_beg) == 0;
 167 }
 168
 169 // According to ARM C++ ABI array cookie consists of two words:
 170 // struct array_cookie {
 171 //   std::size_t element_size; // element_size != 0
 172 //   std::size_t element_count;
 173 // };
 174 static inline bool IsARMABIArrayCookie(uptr chunk_beg, uptr chunk_size,
 175                                        uptr addr) {
 176   return chunk_size == 2 * sizeof(uptr) && chunk_beg + chunk_size == addr &&
 177          *reinterpret_cast<uptr *>(chunk_beg + sizeof(uptr)) == 0;
 178 }
 179
 180 // Special case for "new T[0]" where T is a type with DTOR.
 181 // new T[0] will allocate a cookie (one or two words) for the array size (0)
 182 // and store a pointer to the end of allocated chunk. The actual cookie layout
 183 // varies between platforms according to their C++ ABI implementation.
 184 inline bool IsSpecialCaseOfOperatorNew0(uptr chunk_beg, uptr chunk_size,
 185                                         uptr addr) {
 186 #if defined(__arm__)
 187   return IsARMABIArrayCookie(chunk_beg, chunk_size, addr);
 188 #else
 189   return IsItaniumABIArrayCookie(chunk_beg, chunk_size, addr);
 190 #endif
 191 }
 192
 193 // The following must be implemented in the parent tool.
 194
 195 void ForEachChunk(ForEachChunkCallback callback, void *arg);
 196 // Returns the address range occupied by the global allocator object.
 197 void GetAllocatorGlobalRange(uptr *begin, uptr *end);
 198 // Wrappers for allocator's ForceLock()/ForceUnlock().
 199 void LockAllocator();
 200 void UnlockAllocator();
 201 // Returns true if [addr, addr + sizeof(void *)) is poisoned.
 202 bool WordIsPoisoned(uptr addr);
 203 // Wrappers for ThreadRegistry access.
 204 void LockThreadRegistry();
 205 void UnlockThreadRegistry();
 206 bool GetThreadRangesLocked(tid_t os_id, uptr *stack_begin, uptr *stack_end,
 207                            uptr *tls_begin, uptr *tls_end, uptr *cache_begin,
 208                            uptr *cache_end, DTLS **dtls);
 209 void ForEachExtraStackRange(tid_t os_id, RangeIteratorCallback callback,
 210                             void *arg);
 211 // If called from the main thread, updates the main thread's TID in the thread
 212 // registry. We need this to handle processes that fork() without a subsequent
 213 // exec(), which invalidates the recorded TID. To update it, we must call
 214 // gettid() from the main thread. Our solution is to call this function before
 215 // leak checking and also before every call to pthread_create() (to handle cases
 216 // where leak checking is initiated from a non-main thread).
 217 void EnsureMainThreadIDIsCorrect();
 218 // If p points into a chunk that has been allocated to the user, returns its
 219 // user-visible address. Otherwise, returns 0.
 220 uptr PointsIntoChunk(void *p);
 221 // Returns address of user-visible chunk contained in this allocator chunk.
 222 uptr GetUserBegin(uptr chunk);
 223 // Helper for __lsan_ignore_object().
 224 IgnoreObjectResult IgnoreObjectLocked(const void *p);
 225
 226 // Return the linker module, if valid for the platform.
 227 LoadedModule *GetLinker();
 228
 229 // Return true if LSan has finished leak checking and reported leaks.
 230 bool HasReportedLeaks();
 231
 232 // Run platform-specific leak handlers.
 233 void HandleLeaks();
 234
 235 // Wrapper for chunk metadata operations.
 236 class LsanMetadata {
 237  public:
 238   // Constructor accepts address of user-visible chunk.
 239   explicit LsanMetadata(uptr chunk);
 240   bool allocated() const;
 241   ChunkTag tag() const;
 242   void set_tag(ChunkTag value);
 243   uptr requested_size() const;
 244   u32 stack_trace_id() const;
 245  private:
 246   void *metadata_;
 247 };
 248
 249 }  // namespace __lsan
 250
 251 extern "C" {
 252 SANITIZER_INTERFACE_ATTRIBUTE SANITIZER_WEAK_ATTRIBUTE
 253 const char *__lsan_default_options();
 254
 255 SANITIZER_INTERFACE_ATTRIBUTE SANITIZER_WEAK_ATTRIBUTE
 256 int __lsan_is_turned_off();
 257
 258 SANITIZER_INTERFACE_ATTRIBUTE SANITIZER_WEAK_ATTRIBUTE
 259 const char *__lsan_default_suppressions();
 260 }  // extern "C"
 261
 262 #endif  // LSAN_COMMON_H