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_interface.h"
  12 #include "sanitizer_common/sanitizer_common.h"
  13 #include "sanitizer_common/sanitizer_placement_new.h"
  14 #include "tsan_mman.h"
  15 #include "tsan_rtl.h"
  16 #include "tsan_report.h"
  17 #include "tsan_flags.h"
  18
  19 // May be overriden by front-end.
  20 extern "C" void WEAK __sanitizer_malloc_hook(void *ptr, uptr size) {
  21   (void)ptr;
  22   (void)size;
  23 }
  24
  25 extern "C" void WEAK __sanitizer_free_hook(void *ptr) {
  26   (void)ptr;
  27 }
  28
  29 namespace __tsan {
  30
  31 struct MapUnmapCallback {
  32   void OnMap(uptr p, uptr size) const { }
  33   void OnUnmap(uptr p, uptr size) const {
  34     // We are about to unmap a chunk of user memory.
  35     // Mark the corresponding shadow memory as not needed.
  36     DontNeedShadowFor(p, size);
  37     // Mark the corresponding meta shadow memory as not needed.
  38     // Note the block does not contain any meta info at this point
  39     // (this happens after free).
  40     const uptr kMetaRatio = kMetaShadowCell / kMetaShadowSize;
  41     const uptr kPageSize = GetPageSizeCached() * kMetaRatio;
  42     // Block came from LargeMmapAllocator, so must be large.
  43     // We rely on this in the calculations below.
  44     CHECK_GE(size, 2 * kPageSize);
  45     uptr diff = RoundUp(p, kPageSize) - p;
  46     if (diff != 0) {
  47       p += diff;
  48       size -= diff;
  49     }
  50     diff = p + size - RoundDown(p + size, kPageSize);
  51     if (diff != 0)
  52       size -= diff;
  53     FlushUnneededShadowMemory((uptr)MemToMeta(p), size / kMetaRatio);
  54   }
  55 };
  56
  57 static char allocator_placeholder[sizeof(Allocator)] ALIGNED(64);
  58 Allocator *allocator() {
  59   return reinterpret_cast<Allocator*>(&allocator_placeholder);
  60 }
  61
  62 void InitializeAllocator() {
  63   allocator()->Init(common_flags()->allocator_may_return_null);
  64 }
  65
  66 void AllocatorThreadStart(ThreadState *thr) {
  67   allocator()->InitCache(&thr->alloc_cache);
  68   internal_allocator()->InitCache(&thr->internal_alloc_cache);
  69 }
  70
  71 void AllocatorThreadFinish(ThreadState *thr) {
  72   allocator()->DestroyCache(&thr->alloc_cache);
  73   internal_allocator()->DestroyCache(&thr->internal_alloc_cache);
  74 }
  75
  76 void AllocatorPrintStats() {
  77   allocator()->PrintStats();
  78 }
  79
  80 static void SignalUnsafeCall(ThreadState *thr, uptr pc) {
  81   if (atomic_load_relaxed(&thr->in_signal_handler) == 0 ||
  82       !flags()->report_signal_unsafe)
  83     return;
  84   VarSizeStackTrace stack;
  85   ObtainCurrentStack(thr, pc, &stack);
  86   if (IsFiredSuppression(ctx, ReportTypeSignalUnsafe, stack))
  87     return;
  88   ThreadRegistryLock l(ctx->thread_registry);
  89   ScopedReport rep(ReportTypeSignalUnsafe);
  90   rep.AddStack(stack, true);
  91   OutputReport(thr, rep);
  92 }
  93
  94 void *user_alloc(ThreadState *thr, uptr pc, uptr sz, uptr align, bool signal) {
  95   if ((sz >= (1ull << 40)) || (align >= (1ull << 40)))
  96     return allocator()->ReturnNullOrDie();
  97   void *p = allocator()->Allocate(&thr->alloc_cache, sz, align);
  98   if (p == 0)
  99     return 0;
 100   if (ctx && ctx->initialized)
 101     OnUserAlloc(thr, pc, (uptr)p, sz, true);
 102   if (signal)
 103     SignalUnsafeCall(thr, pc);
 104   return p;
 105 }
 106
 107 void *user_calloc(ThreadState *thr, uptr pc, uptr size, uptr n) {
 108   if (CallocShouldReturnNullDueToOverflow(size, n))
 109     return allocator()->ReturnNullOrDie();
 110   void *p = user_alloc(thr, pc, n * size);
 111   if (p)
 112     internal_memset(p, 0, n * size);
 113   return p;
 114 }
 115
 116 void user_free(ThreadState *thr, uptr pc, void *p, bool signal) {
 117   if (ctx && ctx->initialized)
 118     OnUserFree(thr, pc, (uptr)p, true);
 119   allocator()->Deallocate(&thr->alloc_cache, p);
 120   if (signal)
 121     SignalUnsafeCall(thr, pc);
 122 }
 123
 124 void OnUserAlloc(ThreadState *thr, uptr pc, uptr p, uptr sz, bool write) {
 125   DPrintf("#%d: alloc(%zu) = %p\n", thr->tid, sz, p);
 126   ctx->metamap.AllocBlock(thr, pc, p, sz);
 127   if (write && thr->ignore_reads_and_writes == 0)
 128     MemoryRangeImitateWrite(thr, pc, (uptr)p, sz);
 129   else
 130     MemoryResetRange(thr, pc, (uptr)p, sz);
 131 }
 132
 133 void OnUserFree(ThreadState *thr, uptr pc, uptr p, bool write) {
 134   CHECK_NE(p, (void*)0);
 135   uptr sz = ctx->metamap.FreeBlock(thr, pc, p);
 136   DPrintf("#%d: free(%p, %zu)\n", thr->tid, p, sz);
 137   if (write && thr->ignore_reads_and_writes == 0)
 138     MemoryRangeFreed(thr, pc, (uptr)p, sz);
 139 }
 140
 141 void *user_realloc(ThreadState *thr, uptr pc, void *p, uptr sz) {
 142   void *p2 = 0;
 143   // FIXME: Handle "shrinking" more efficiently,
 144   // it seems that some software actually does this.
 145   if (sz) {
 146     p2 = user_alloc(thr, pc, sz);
 147     if (p2 == 0)
 148       return 0;
 149     if (p) {
 150       uptr oldsz = user_alloc_usable_size(p);
 151       internal_memcpy(p2, p, min(oldsz, sz));
 152     }
 153   }
 154   if (p)
 155     user_free(thr, pc, p);
 156   return p2;
 157 }
 158
 159 uptr user_alloc_usable_size(const void *p) {
 160   if (p == 0)
 161     return 0;
 162   MBlock *b = ctx->metamap.GetBlock((uptr)p);
 163   return b ? b->siz : 0;
 164 }
 165
 166 void invoke_malloc_hook(void *ptr, uptr size) {
 167   ThreadState *thr = cur_thread();
 168   if (ctx == 0 || !ctx->initialized || thr->ignore_interceptors)
 169     return;
 170   __sanitizer_malloc_hook(ptr, size);
 171 }
 172
 173 void invoke_free_hook(void *ptr) {
 174   ThreadState *thr = cur_thread();
 175   if (ctx == 0 || !ctx->initialized || thr->ignore_interceptors)
 176     return;
 177   __sanitizer_free_hook(ptr);
 178 }
 179
 180 void *internal_alloc(MBlockType typ, uptr sz) {
 181   ThreadState *thr = cur_thread();
 182   if (thr->nomalloc) {
 183     thr->nomalloc = 0;  // CHECK calls internal_malloc().
 184     CHECK(0);
 185   }
 186   return InternalAlloc(sz, &thr->internal_alloc_cache);
 187 }
 188
 189 void internal_free(void *p) {
 190   ThreadState *thr = cur_thread();
 191   if (thr->nomalloc) {
 192     thr->nomalloc = 0;  // CHECK calls internal_malloc().
 193     CHECK(0);
 194   }
 195   InternalFree(p, &thr->internal_alloc_cache);
 196 }
 197
 198 }  // namespace __tsan
 199
 200 using namespace __tsan;
 201
 202 extern "C" {
 203 uptr __sanitizer_get_current_allocated_bytes() {
 204   uptr stats[AllocatorStatCount];
 205   allocator()->GetStats(stats);
 206   return stats[AllocatorStatAllocated];
 207 }
 208
 209 uptr __sanitizer_get_heap_size() {
 210   uptr stats[AllocatorStatCount];
 211   allocator()->GetStats(stats);
 212   return stats[AllocatorStatMapped];
 213 }
 214
 215 uptr __sanitizer_get_free_bytes() {
 216   return 1;
 217 }
 218
 219 uptr __sanitizer_get_unmapped_bytes() {
 220   return 1;
 221 }
 222
 223 uptr __sanitizer_get_estimated_allocated_size(uptr size) {
 224   return size;
 225 }
 226
 227 int __sanitizer_get_ownership(const void *p) {
 228   return allocator()->GetBlockBegin(p) != 0;
 229 }
 230
 231 uptr __sanitizer_get_allocated_size(const void *p) {
 232   return user_alloc_usable_size(p);
 233 }
 234
 235 void __tsan_on_thread_idle() {
 236   ThreadState *thr = cur_thread();
 237   allocator()->SwallowCache(&thr->alloc_cache);
 238   internal_allocator()->SwallowCache(&thr->internal_alloc_cache);
 239   ctx->metamap.OnThreadIdle(thr);
 240 }
 241 }  // extern "C"