libsanitizer/tsan/tsan_mman.cc

   1 //===-- tsan_mman.cc ------------------------------------------------------===//
   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 ThreadSanitizer (TSan), a race detector.
   9 //
  10 //===----------------------------------------------------------------------===//
  11 #include "sanitizer_common/sanitizer_allocator_checks.h"
  12 #include "sanitizer_common/sanitizer_allocator_interface.h"
  13 #include "sanitizer_common/sanitizer_common.h"
  14 #include "sanitizer_common/sanitizer_errno.h"
  15 #include "sanitizer_common/sanitizer_placement_new.h"
  16 #include "tsan_mman.h"
  17 #include "tsan_rtl.h"
  18 #include "tsan_report.h"
  19 #include "tsan_flags.h"
  20
  21 // May be overriden by front-end.
  22 SANITIZER_WEAK_DEFAULT_IMPL
  23 void __sanitizer_malloc_hook(void *ptr, uptr size) {
  24   (void)ptr;
  25   (void)size;
  26 }
  27
  28 SANITIZER_WEAK_DEFAULT_IMPL
  29 void __sanitizer_free_hook(void *ptr) {
  30   (void)ptr;
  31 }
  32
  33 namespace __tsan {
  34
  35 struct MapUnmapCallback {
  36   void OnMap(uptr p, uptr size) const { }
  37   void OnUnmap(uptr p, uptr size) const {
  38     // We are about to unmap a chunk of user memory.
  39     // Mark the corresponding shadow memory as not needed.
  40     DontNeedShadowFor(p, size);
  41     // Mark the corresponding meta shadow memory as not needed.
  42     // Note the block does not contain any meta info at this point
  43     // (this happens after free).
  44     const uptr kMetaRatio = kMetaShadowCell / kMetaShadowSize;
  45     const uptr kPageSize = GetPageSizeCached() * kMetaRatio;
  46     // Block came from LargeMmapAllocator, so must be large.
  47     // We rely on this in the calculations below.
  48     CHECK_GE(size, 2 * kPageSize);
  49     uptr diff = RoundUp(p, kPageSize) - p;
  50     if (diff != 0) {
  51       p += diff;
  52       size -= diff;
  53     }
  54     diff = p + size - RoundDown(p + size, kPageSize);
  55     if (diff != 0)
  56       size -= diff;
  57     uptr p_meta = (uptr)MemToMeta(p);
  58     ReleaseMemoryPagesToOS(p_meta, p_meta + size / kMetaRatio);
  59   }
  60 };
  61
  62 static char allocator_placeholder[sizeof(Allocator)] ALIGNED(64);
  63 Allocator *allocator() {
  64   return reinterpret_cast<Allocator*>(&allocator_placeholder);
  65 }
  66
  67 struct GlobalProc {
  68   Mutex mtx;
  69   Processor *proc;
  70
  71   GlobalProc()
  72       : mtx(MutexTypeGlobalProc, StatMtxGlobalProc)
  73       , proc(ProcCreate()) {
  74   }
  75 };
  76
  77 static char global_proc_placeholder[sizeof(GlobalProc)] ALIGNED(64);
  78 GlobalProc *global_proc() {
  79   return reinterpret_cast<GlobalProc*>(&global_proc_placeholder);
  80 }
  81
  82 ScopedGlobalProcessor::ScopedGlobalProcessor() {
  83   GlobalProc *gp = global_proc();
  84   ThreadState *thr = cur_thread();
  85   if (thr->proc())
  86     return;
  87   // If we don't have a proc, use the global one.
  88   // There are currently only two known case where this path is triggered:
  89   //   __interceptor_free
  90   //   __nptl_deallocate_tsd
  91   //   start_thread
  92   //   clone
  93   // and:
  94   //   ResetRange
  95   //   __interceptor_munmap
  96   //   __deallocate_stack
  97   //   start_thread
  98   //   clone
  99   // Ideally, we destroy thread state (and unwire proc) when a thread actually
 100   // exits (i.e. when we join/wait it). Then we would not need the global proc
 101   gp->mtx.Lock();
 102   ProcWire(gp->proc, thr);
 103 }
 104
 105 ScopedGlobalProcessor::~ScopedGlobalProcessor() {
 106   GlobalProc *gp = global_proc();
 107   ThreadState *thr = cur_thread();
 108   if (thr->proc() != gp->proc)
 109     return;
 110   ProcUnwire(gp->proc, thr);
 111   gp->mtx.Unlock();
 112 }
 113
 114 void InitializeAllocator() {
 115   SetAllocatorMayReturnNull(common_flags()->allocator_may_return_null);
 116   allocator()->Init(common_flags()->allocator_release_to_os_interval_ms);
 117 }
 118
 119 void InitializeAllocatorLate() {
 120   new(global_proc()) GlobalProc();
 121 }
 122
 123 void AllocatorProcStart(Processor *proc) {
 124   allocator()->InitCache(&proc->alloc_cache);
 125   internal_allocator()->InitCache(&proc->internal_alloc_cache);
 126 }
 127
 128 void AllocatorProcFinish(Processor *proc) {
 129   allocator()->DestroyCache(&proc->alloc_cache);
 130   internal_allocator()->DestroyCache(&proc->internal_alloc_cache);
 131 }
 132
 133 void AllocatorPrintStats() {
 134   allocator()->PrintStats();
 135 }
 136
 137 static void SignalUnsafeCall(ThreadState *thr, uptr pc) {
 138   if (atomic_load_relaxed(&thr->in_signal_handler) == 0 ||
 139       !flags()->report_signal_unsafe)
 140     return;
 141   VarSizeStackTrace stack;
 142   ObtainCurrentStack(thr, pc, &stack);
 143   if (IsFiredSuppression(ctx, ReportTypeSignalUnsafe, stack))
 144     return;
 145   ThreadRegistryLock l(ctx->thread_registry);
 146   ScopedReport rep(ReportTypeSignalUnsafe);
 147   rep.AddStack(stack, true);
 148   OutputReport(thr, rep);
 149 }
 150
 151 void *user_alloc_internal(ThreadState *thr, uptr pc, uptr sz, uptr align,
 152                           bool signal) {
 153   if ((sz >= (1ull << 40)) || (align >= (1ull << 40)))
 154     return Allocator::FailureHandler::OnBadRequest();
 155   void *p = allocator()->Allocate(&thr->proc()->alloc_cache, sz, align);
 156   if (UNLIKELY(p == 0))
 157     return 0;
 158   if (ctx && ctx->initialized)
 159     OnUserAlloc(thr, pc, (uptr)p, sz, true);
 160   if (signal)
 161     SignalUnsafeCall(thr, pc);
 162   return p;
 163 }
 164
 165 void user_free(ThreadState *thr, uptr pc, void *p, bool signal) {
 166   ScopedGlobalProcessor sgp;
 167   if (ctx && ctx->initialized)
 168     OnUserFree(thr, pc, (uptr)p, true);
 169   allocator()->Deallocate(&thr->proc()->alloc_cache, p);
 170   if (signal)
 171     SignalUnsafeCall(thr, pc);
 172 }
 173
 174 void *user_alloc(ThreadState *thr, uptr pc, uptr sz) {
 175   return SetErrnoOnNull(user_alloc_internal(thr, pc, sz, kDefaultAlignment));
 176 }
 177
 178 void *user_calloc(ThreadState *thr, uptr pc, uptr size, uptr n) {
 179   if (UNLIKELY(CheckForCallocOverflow(size, n)))
 180     return SetErrnoOnNull(Allocator::FailureHandler::OnBadRequest());
 181   void *p = user_alloc_internal(thr, pc, n * size);
 182   if (p)
 183     internal_memset(p, 0, n * size);
 184   return SetErrnoOnNull(p);
 185 }
 186
 187 void OnUserAlloc(ThreadState *thr, uptr pc, uptr p, uptr sz, bool write) {
 188   DPrintf("#%d: alloc(%zu) = %p\n", thr->tid, sz, p);
 189   ctx->metamap.AllocBlock(thr, pc, p, sz);
 190   if (write && thr->ignore_reads_and_writes == 0)
 191     MemoryRangeImitateWrite(thr, pc, (uptr)p, sz);
 192   else
 193     MemoryResetRange(thr, pc, (uptr)p, sz);
 194 }
 195
 196 void OnUserFree(ThreadState *thr, uptr pc, uptr p, bool write) {
 197   CHECK_NE(p, (void*)0);
 198   uptr sz = ctx->metamap.FreeBlock(thr->proc(), p);
 199   DPrintf("#%d: free(%p, %zu)\n", thr->tid, p, sz);
 200   if (write && thr->ignore_reads_and_writes == 0)
 201     MemoryRangeFreed(thr, pc, (uptr)p, sz);
 202 }
 203
 204 void *user_realloc(ThreadState *thr, uptr pc, void *p, uptr sz) {
 205   // FIXME: Handle "shrinking" more efficiently,
 206   // it seems that some software actually does this.
 207   if (!p)
 208     return SetErrnoOnNull(user_alloc_internal(thr, pc, sz));
 209   if (!sz) {
 210     user_free(thr, pc, p);
 211     return nullptr;
 212   }
 213   void *new_p = user_alloc_internal(thr, pc, sz);
 214   if (new_p) {
 215     uptr old_sz = user_alloc_usable_size(p);
 216     internal_memcpy(new_p, p, min(old_sz, sz));
 217     user_free(thr, pc, p);
 218   }
 219   return SetErrnoOnNull(new_p);
 220 }
 221
 222 void *user_memalign(ThreadState *thr, uptr pc, uptr align, uptr sz) {
 223   if (UNLIKELY(!IsPowerOfTwo(align))) {
 224     errno = errno_EINVAL;
 225     return Allocator::FailureHandler::OnBadRequest();
 226   }
 227   return SetErrnoOnNull(user_alloc_internal(thr, pc, sz, align));
 228 }
 229
 230 int user_posix_memalign(ThreadState *thr, uptr pc, void **memptr, uptr align,
 231                         uptr sz) {
 232   if (UNLIKELY(!CheckPosixMemalignAlignment(align))) {
 233     Allocator::FailureHandler::OnBadRequest();
 234     return errno_EINVAL;
 235   }
 236   void *ptr = user_alloc_internal(thr, pc, sz, align);
 237   if (UNLIKELY(!ptr))
 238     return errno_ENOMEM;
 239   CHECK(IsAligned((uptr)ptr, align));
 240   *memptr = ptr;
 241   return 0;
 242 }
 243
 244 void *user_aligned_alloc(ThreadState *thr, uptr pc, uptr align, uptr sz) {
 245   if (UNLIKELY(!CheckAlignedAllocAlignmentAndSize(align, sz))) {
 246     errno = errno_EINVAL;
 247     return Allocator::FailureHandler::OnBadRequest();
 248   }
 249   return SetErrnoOnNull(user_alloc_internal(thr, pc, sz, align));
 250 }
 251
 252 void *user_valloc(ThreadState *thr, uptr pc, uptr sz) {
 253   return SetErrnoOnNull(user_alloc_internal(thr, pc, sz, GetPageSizeCached()));
 254 }
 255
 256 void *user_pvalloc(ThreadState *thr, uptr pc, uptr sz) {
 257   uptr PageSize = GetPageSizeCached();
 258   if (UNLIKELY(CheckForPvallocOverflow(sz, PageSize))) {
 259     errno = errno_ENOMEM;
 260     return Allocator::FailureHandler::OnBadRequest();
 261   }
 262   // pvalloc(0) should allocate one page.
 263   sz = sz ? RoundUpTo(sz, PageSize) : PageSize;
 264   return SetErrnoOnNull(user_alloc_internal(thr, pc, sz, PageSize));
 265 }
 266
 267 uptr user_alloc_usable_size(const void *p) {
 268   if (p == 0)
 269     return 0;
 270   MBlock *b = ctx->metamap.GetBlock((uptr)p);
 271   if (!b)
 272     return 0;  // Not a valid pointer.
 273   if (b->siz == 0)
 274     return 1;  // Zero-sized allocations are actually 1 byte.
 275   return b->siz;
 276 }
 277
 278 void invoke_malloc_hook(void *ptr, uptr size) {
 279   ThreadState *thr = cur_thread();
 280   if (ctx == 0 || !ctx->initialized || thr->ignore_interceptors)
 281     return;
 282   __sanitizer_malloc_hook(ptr, size);
 283   RunMallocHooks(ptr, size);
 284 }
 285
 286 void invoke_free_hook(void *ptr) {
 287   ThreadState *thr = cur_thread();
 288   if (ctx == 0 || !ctx->initialized || thr->ignore_interceptors)
 289     return;
 290   __sanitizer_free_hook(ptr);
 291   RunFreeHooks(ptr);
 292 }
 293
 294 void *internal_alloc(MBlockType typ, uptr sz) {
 295   ThreadState *thr = cur_thread();
 296   if (thr->nomalloc) {
 297     thr->nomalloc = 0;  // CHECK calls internal_malloc().
 298     CHECK(0);
 299   }
 300   return InternalAlloc(sz, &thr->proc()->internal_alloc_cache);
 301 }
 302
 303 void internal_free(void *p) {
 304   ThreadState *thr = cur_thread();
 305   if (thr->nomalloc) {
 306     thr->nomalloc = 0;  // CHECK calls internal_malloc().
 307     CHECK(0);
 308   }
 309   InternalFree(p, &thr->proc()->internal_alloc_cache);
 310 }
 311
 312 }  // namespace __tsan
 313
 314 using namespace __tsan;
 315
 316 extern "C" {
 317 uptr __sanitizer_get_current_allocated_bytes() {
 318   uptr stats[AllocatorStatCount];
 319   allocator()->GetStats(stats);
 320   return stats[AllocatorStatAllocated];
 321 }
 322
 323 uptr __sanitizer_get_heap_size() {
 324   uptr stats[AllocatorStatCount];
 325   allocator()->GetStats(stats);
 326   return stats[AllocatorStatMapped];
 327 }
 328
 329 uptr __sanitizer_get_free_bytes() {
 330   return 1;
 331 }
 332
 333 uptr __sanitizer_get_unmapped_bytes() {
 334   return 1;
 335 }
 336
 337 uptr __sanitizer_get_estimated_allocated_size(uptr size) {
 338   return size;
 339 }
 340
 341 int __sanitizer_get_ownership(const void *p) {
 342   return allocator()->GetBlockBegin(p) != 0;
 343 }
 344
 345 uptr __sanitizer_get_allocated_size(const void *p) {
 346   return user_alloc_usable_size(p);
 347 }
 348
 349 void __tsan_on_thread_idle() {
 350   ThreadState *thr = cur_thread();
 351   thr->clock.ResetCached(&thr->proc()->clock_cache);
 352   thr->last_sleep_clock.ResetCached(&thr->proc()->clock_cache);
 353   allocator()->SwallowCache(&thr->proc()->alloc_cache);
 354   internal_allocator()->SwallowCache(&thr->proc()->internal_alloc_cache);
 355   ctx->metamap.OnProcIdle(thr->proc());
 356 }
 357 }  // extern "C"