libsanitizer/tsan/tsan_mman.cpp

   1 //===-- tsan_mman.cpp -----------------------------------------------------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8 //
   9 // This file is a part of ThreadSanitizer (TSan), a race detector.
  10 //
  11 //===----------------------------------------------------------------------===//
  12 #include "sanitizer_common/sanitizer_allocator_checks.h"
  13 #include "sanitizer_common/sanitizer_allocator_interface.h"
  14 #include "sanitizer_common/sanitizer_allocator_report.h"
  15 #include "sanitizer_common/sanitizer_common.h"
  16 #include "sanitizer_common/sanitizer_errno.h"
  17 #include "sanitizer_common/sanitizer_placement_new.h"
  18 #include "tsan_mman.h"
  19 #include "tsan_rtl.h"
  20 #include "tsan_report.h"
  21 #include "tsan_flags.h"
  22
  23 // May be overriden by front-end.
  24 SANITIZER_WEAK_DEFAULT_IMPL
  25 void __sanitizer_malloc_hook(void *ptr, uptr size) {
  26   (void)ptr;
  27   (void)size;
  28 }
  29
  30 SANITIZER_WEAK_DEFAULT_IMPL
  31 void __sanitizer_free_hook(void *ptr) {
  32   (void)ptr;
  33 }
  34
  35 namespace __tsan {
  36
  37 struct MapUnmapCallback {
  38   void OnMap(uptr p, uptr size) const { }
  39   void OnUnmap(uptr p, uptr size) const {
  40     // We are about to unmap a chunk of user memory.
  41     // Mark the corresponding shadow memory as not needed.
  42     DontNeedShadowFor(p, size);
  43     // Mark the corresponding meta shadow memory as not needed.
  44     // Note the block does not contain any meta info at this point
  45     // (this happens after free).
  46     const uptr kMetaRatio = kMetaShadowCell / kMetaShadowSize;
  47     const uptr kPageSize = GetPageSizeCached() * kMetaRatio;
  48     // Block came from LargeMmapAllocator, so must be large.
  49     // We rely on this in the calculations below.
  50     CHECK_GE(size, 2 * kPageSize);
  51     uptr diff = RoundUp(p, kPageSize) - p;
  52     if (diff != 0) {
  53       p += diff;
  54       size -= diff;
  55     }
  56     diff = p + size - RoundDown(p + size, kPageSize);
  57     if (diff != 0)
  58       size -= diff;
  59     uptr p_meta = (uptr)MemToMeta(p);
  60     ReleaseMemoryPagesToOS(p_meta, p_meta + size / kMetaRatio);
  61   }
  62 };
  63
  64 static char allocator_placeholder[sizeof(Allocator)] ALIGNED(64);
  65 Allocator *allocator() {
  66   return reinterpret_cast<Allocator*>(&allocator_placeholder);
  67 }
  68
  69 struct GlobalProc {
  70   Mutex mtx;
  71   Processor *proc;
  72
  73   GlobalProc()
  74       : mtx(MutexTypeGlobalProc, StatMtxGlobalProc)
  75       , proc(ProcCreate()) {
  76   }
  77 };
  78
  79 static char global_proc_placeholder[sizeof(GlobalProc)] ALIGNED(64);
  80 GlobalProc *global_proc() {
  81   return reinterpret_cast<GlobalProc*>(&global_proc_placeholder);
  82 }
  83
  84 ScopedGlobalProcessor::ScopedGlobalProcessor() {
  85   GlobalProc *gp = global_proc();
  86   ThreadState *thr = cur_thread();
  87   if (thr->proc())
  88     return;
  89   // If we don't have a proc, use the global one.
  90   // There are currently only two known case where this path is triggered:
  91   //   __interceptor_free
  92   //   __nptl_deallocate_tsd
  93   //   start_thread
  94   //   clone
  95   // and:
  96   //   ResetRange
  97   //   __interceptor_munmap
  98   //   __deallocate_stack
  99   //   start_thread
 100   //   clone
 101   // Ideally, we destroy thread state (and unwire proc) when a thread actually
 102   // exits (i.e. when we join/wait it). Then we would not need the global proc
 103   gp->mtx.Lock();
 104   ProcWire(gp->proc, thr);
 105 }
 106
 107 ScopedGlobalProcessor::~ScopedGlobalProcessor() {
 108   GlobalProc *gp = global_proc();
 109   ThreadState *thr = cur_thread();
 110   if (thr->proc() != gp->proc)
 111     return;
 112   ProcUnwire(gp->proc, thr);
 113   gp->mtx.Unlock();
 114 }
 115
 116 static constexpr uptr kMaxAllowedMallocSize = 1ull << 40;
 117 static uptr max_user_defined_malloc_size;
 118
 119 void InitializeAllocator() {
 120   SetAllocatorMayReturnNull(common_flags()->allocator_may_return_null);
 121   allocator()->Init(common_flags()->allocator_release_to_os_interval_ms);
 122   max_user_defined_malloc_size = common_flags()->max_allocation_size_mb
 123                                      ? common_flags()->max_allocation_size_mb
 124                                            << 20
 125                                      : kMaxAllowedMallocSize;
 126 }
 127
 128 void InitializeAllocatorLate() {
 129   new(global_proc()) GlobalProc();
 130 }
 131
 132 void AllocatorProcStart(Processor *proc) {
 133   allocator()->InitCache(&proc->alloc_cache);
 134   internal_allocator()->InitCache(&proc->internal_alloc_cache);
 135 }
 136
 137 void AllocatorProcFinish(Processor *proc) {
 138   allocator()->DestroyCache(&proc->alloc_cache);
 139   internal_allocator()->DestroyCache(&proc->internal_alloc_cache);
 140 }
 141
 142 void AllocatorPrintStats() {
 143   allocator()->PrintStats();
 144 }
 145
 146 static void SignalUnsafeCall(ThreadState *thr, uptr pc) {
 147   if (atomic_load_relaxed(&thr->in_signal_handler) == 0 ||
 148       !flags()->report_signal_unsafe)
 149     return;
 150   VarSizeStackTrace stack;
 151   ObtainCurrentStack(thr, pc, &stack);
 152   if (IsFiredSuppression(ctx, ReportTypeSignalUnsafe, stack))
 153     return;
 154   ThreadRegistryLock l(ctx->thread_registry);
 155   ScopedReport rep(ReportTypeSignalUnsafe);
 156   rep.AddStack(stack, true);
 157   OutputReport(thr, rep);
 158 }
 159
 160
 161 void *user_alloc_internal(ThreadState *thr, uptr pc, uptr sz, uptr align,
 162                           bool signal) {
 163   if (sz >= kMaxAllowedMallocSize || align >= kMaxAllowedMallocSize ||
 164       sz > max_user_defined_malloc_size) {
 165     if (AllocatorMayReturnNull())
 166       return nullptr;
 167     uptr malloc_limit =
 168         Min(kMaxAllowedMallocSize, max_user_defined_malloc_size);
 169     GET_STACK_TRACE_FATAL(thr, pc);
 170     ReportAllocationSizeTooBig(sz, malloc_limit, &stack);
 171   }
 172   void *p = allocator()->Allocate(&thr->proc()->alloc_cache, sz, align);
 173   if (UNLIKELY(!p)) {
 174     SetAllocatorOutOfMemory();
 175     if (AllocatorMayReturnNull())
 176       return nullptr;
 177     GET_STACK_TRACE_FATAL(thr, pc);
 178     ReportOutOfMemory(sz, &stack);
 179   }
 180   if (ctx && ctx->initialized)
 181     OnUserAlloc(thr, pc, (uptr)p, sz, true);
 182   if (signal)
 183     SignalUnsafeCall(thr, pc);
 184   return p;
 185 }
 186
 187 void user_free(ThreadState *thr, uptr pc, void *p, bool signal) {
 188   ScopedGlobalProcessor sgp;
 189   if (ctx && ctx->initialized)
 190     OnUserFree(thr, pc, (uptr)p, true);
 191   allocator()->Deallocate(&thr->proc()->alloc_cache, p);
 192   if (signal)
 193     SignalUnsafeCall(thr, pc);
 194 }
 195
 196 void *user_alloc(ThreadState *thr, uptr pc, uptr sz) {
 197   return SetErrnoOnNull(user_alloc_internal(thr, pc, sz, kDefaultAlignment));
 198 }
 199
 200 void *user_calloc(ThreadState *thr, uptr pc, uptr size, uptr n) {
 201   if (UNLIKELY(CheckForCallocOverflow(size, n))) {
 202     if (AllocatorMayReturnNull())
 203       return SetErrnoOnNull(nullptr);
 204     GET_STACK_TRACE_FATAL(thr, pc);
 205     ReportCallocOverflow(n, size, &stack);
 206   }
 207   void *p = user_alloc_internal(thr, pc, n * size);
 208   if (p)
 209     internal_memset(p, 0, n * size);
 210   return SetErrnoOnNull(p);
 211 }
 212
 213 void *user_reallocarray(ThreadState *thr, uptr pc, void *p, uptr size, uptr n) {
 214   if (UNLIKELY(CheckForCallocOverflow(size, n))) {
 215     if (AllocatorMayReturnNull())
 216       return SetErrnoOnNull(nullptr);
 217     GET_STACK_TRACE_FATAL(thr, pc);
 218     ReportReallocArrayOverflow(size, n, &stack);
 219   }
 220   return user_realloc(thr, pc, p, size * n);
 221 }
 222
 223 void OnUserAlloc(ThreadState *thr, uptr pc, uptr p, uptr sz, bool write) {
 224   DPrintf("#%d: alloc(%zu) = %p\n", thr->tid, sz, p);
 225   ctx->metamap.AllocBlock(thr, pc, p, sz);
 226   if (write && thr->ignore_reads_and_writes == 0)
 227     MemoryRangeImitateWrite(thr, pc, (uptr)p, sz);
 228   else
 229     MemoryResetRange(thr, pc, (uptr)p, sz);
 230 }
 231
 232 void OnUserFree(ThreadState *thr, uptr pc, uptr p, bool write) {
 233   CHECK_NE(p, (void*)0);
 234   uptr sz = ctx->metamap.FreeBlock(thr->proc(), p);
 235   DPrintf("#%d: free(%p, %zu)\n", thr->tid, p, sz);
 236   if (write && thr->ignore_reads_and_writes == 0)
 237     MemoryRangeFreed(thr, pc, (uptr)p, sz);
 238 }
 239
 240 void *user_realloc(ThreadState *thr, uptr pc, void *p, uptr sz) {
 241   // FIXME: Handle "shrinking" more efficiently,
 242   // it seems that some software actually does this.
 243   if (!p)
 244     return SetErrnoOnNull(user_alloc_internal(thr, pc, sz));
 245   if (!sz) {
 246     user_free(thr, pc, p);
 247     return nullptr;
 248   }
 249   void *new_p = user_alloc_internal(thr, pc, sz);
 250   if (new_p) {
 251     uptr old_sz = user_alloc_usable_size(p);
 252     internal_memcpy(new_p, p, min(old_sz, sz));
 253     user_free(thr, pc, p);
 254   }
 255   return SetErrnoOnNull(new_p);
 256 }
 257
 258 void *user_memalign(ThreadState *thr, uptr pc, uptr align, uptr sz) {
 259   if (UNLIKELY(!IsPowerOfTwo(align))) {
 260     errno = errno_EINVAL;
 261     if (AllocatorMayReturnNull())
 262       return nullptr;
 263     GET_STACK_TRACE_FATAL(thr, pc);
 264     ReportInvalidAllocationAlignment(align, &stack);
 265   }
 266   return SetErrnoOnNull(user_alloc_internal(thr, pc, sz, align));
 267 }
 268
 269 int user_posix_memalign(ThreadState *thr, uptr pc, void **memptr, uptr align,
 270                         uptr sz) {
 271   if (UNLIKELY(!CheckPosixMemalignAlignment(align))) {
 272     if (AllocatorMayReturnNull())
 273       return errno_EINVAL;
 274     GET_STACK_TRACE_FATAL(thr, pc);
 275     ReportInvalidPosixMemalignAlignment(align, &stack);
 276   }
 277   void *ptr = user_alloc_internal(thr, pc, sz, align);
 278   if (UNLIKELY(!ptr))
 279     // OOM error is already taken care of by user_alloc_internal.
 280     return errno_ENOMEM;
 281   CHECK(IsAligned((uptr)ptr, align));
 282   *memptr = ptr;
 283   return 0;
 284 }
 285
 286 void *user_aligned_alloc(ThreadState *thr, uptr pc, uptr align, uptr sz) {
 287   if (UNLIKELY(!CheckAlignedAllocAlignmentAndSize(align, sz))) {
 288     errno = errno_EINVAL;
 289     if (AllocatorMayReturnNull())
 290       return nullptr;
 291     GET_STACK_TRACE_FATAL(thr, pc);
 292     ReportInvalidAlignedAllocAlignment(sz, align, &stack);
 293   }
 294   return SetErrnoOnNull(user_alloc_internal(thr, pc, sz, align));
 295 }
 296
 297 void *user_valloc(ThreadState *thr, uptr pc, uptr sz) {
 298   return SetErrnoOnNull(user_alloc_internal(thr, pc, sz, GetPageSizeCached()));
 299 }
 300
 301 void *user_pvalloc(ThreadState *thr, uptr pc, uptr sz) {
 302   uptr PageSize = GetPageSizeCached();
 303   if (UNLIKELY(CheckForPvallocOverflow(sz, PageSize))) {
 304     errno = errno_ENOMEM;
 305     if (AllocatorMayReturnNull())
 306       return nullptr;
 307     GET_STACK_TRACE_FATAL(thr, pc);
 308     ReportPvallocOverflow(sz, &stack);
 309   }
 310   // pvalloc(0) should allocate one page.
 311   sz = sz ? RoundUpTo(sz, PageSize) : PageSize;
 312   return SetErrnoOnNull(user_alloc_internal(thr, pc, sz, PageSize));
 313 }
 314
 315 uptr user_alloc_usable_size(const void *p) {
 316   if (p == 0)
 317     return 0;
 318   MBlock *b = ctx->metamap.GetBlock((uptr)p);
 319   if (!b)
 320     return 0;  // Not a valid pointer.
 321   if (b->siz == 0)
 322     return 1;  // Zero-sized allocations are actually 1 byte.
 323   return b->siz;
 324 }
 325
 326 void invoke_malloc_hook(void *ptr, uptr size) {
 327   ThreadState *thr = cur_thread();
 328   if (ctx == 0 || !ctx->initialized || thr->ignore_interceptors)
 329     return;
 330   __sanitizer_malloc_hook(ptr, size);
 331   RunMallocHooks(ptr, size);
 332 }
 333
 334 void invoke_free_hook(void *ptr) {
 335   ThreadState *thr = cur_thread();
 336   if (ctx == 0 || !ctx->initialized || thr->ignore_interceptors)
 337     return;
 338   __sanitizer_free_hook(ptr);
 339   RunFreeHooks(ptr);
 340 }
 341
 342 void *internal_alloc(MBlockType typ, uptr sz) {
 343   ThreadState *thr = cur_thread();
 344   if (thr->nomalloc) {
 345     thr->nomalloc = 0;  // CHECK calls internal_malloc().
 346     CHECK(0);
 347   }
 348   return InternalAlloc(sz, &thr->proc()->internal_alloc_cache);
 349 }
 350
 351 void internal_free(void *p) {
 352   ThreadState *thr = cur_thread();
 353   if (thr->nomalloc) {
 354     thr->nomalloc = 0;  // CHECK calls internal_malloc().
 355     CHECK(0);
 356   }
 357   InternalFree(p, &thr->proc()->internal_alloc_cache);
 358 }
 359
 360 }  // namespace __tsan
 361
 362 using namespace __tsan;
 363
 364 extern "C" {
 365 uptr __sanitizer_get_current_allocated_bytes() {
 366   uptr stats[AllocatorStatCount];
 367   allocator()->GetStats(stats);
 368   return stats[AllocatorStatAllocated];
 369 }
 370
 371 uptr __sanitizer_get_heap_size() {
 372   uptr stats[AllocatorStatCount];
 373   allocator()->GetStats(stats);
 374   return stats[AllocatorStatMapped];
 375 }
 376
 377 uptr __sanitizer_get_free_bytes() {
 378   return 1;
 379 }
 380
 381 uptr __sanitizer_get_unmapped_bytes() {
 382   return 1;
 383 }
 384
 385 uptr __sanitizer_get_estimated_allocated_size(uptr size) {
 386   return size;
 387 }
 388
 389 int __sanitizer_get_ownership(const void *p) {
 390   return allocator()->GetBlockBegin(p) != 0;
 391 }
 392
 393 uptr __sanitizer_get_allocated_size(const void *p) {
 394   return user_alloc_usable_size(p);
 395 }
 396
 397 void __tsan_on_thread_idle() {
 398   ThreadState *thr = cur_thread();
 399   thr->clock.ResetCached(&thr->proc()->clock_cache);
 400   thr->last_sleep_clock.ResetCached(&thr->proc()->clock_cache);
 401   allocator()->SwallowCache(&thr->proc()->alloc_cache);
 402   internal_allocator()->SwallowCache(&thr->proc()->internal_alloc_cache);
 403   ctx->metamap.OnProcIdle(thr->proc());
 404 }
 405 }  // extern "C"