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() : mtx(MutexTypeGlobalProc), proc(ProcCreate()) {}
  74 };
  75
  76 static char global_proc_placeholder[sizeof(GlobalProc)] ALIGNED(64);
  77 GlobalProc *global_proc() {
  78   return reinterpret_cast<GlobalProc*>(&global_proc_placeholder);
  79 }
  80
  81 ScopedGlobalProcessor::ScopedGlobalProcessor() {
  82   GlobalProc *gp = global_proc();
  83   ThreadState *thr = cur_thread();
  84   if (thr->proc())
  85     return;
  86   // If we don't have a proc, use the global one.
  87   // There are currently only two known case where this path is triggered:
  88   //   __interceptor_free
  89   //   __nptl_deallocate_tsd
  90   //   start_thread
  91   //   clone
  92   // and:
  93   //   ResetRange
  94   //   __interceptor_munmap
  95   //   __deallocate_stack
  96   //   start_thread
  97   //   clone
  98   // Ideally, we destroy thread state (and unwire proc) when a thread actually
  99   // exits (i.e. when we join/wait it). Then we would not need the global proc
 100   gp->mtx.Lock();
 101   ProcWire(gp->proc, thr);
 102 }
 103
 104 ScopedGlobalProcessor::~ScopedGlobalProcessor() {
 105   GlobalProc *gp = global_proc();
 106   ThreadState *thr = cur_thread();
 107   if (thr->proc() != gp->proc)
 108     return;
 109   ProcUnwire(gp->proc, thr);
 110   gp->mtx.Unlock();
 111 }
 112
 113 static constexpr uptr kMaxAllowedMallocSize = 1ull << 40;
 114 static uptr max_user_defined_malloc_size;
 115
 116 void InitializeAllocator() {
 117   SetAllocatorMayReturnNull(common_flags()->allocator_may_return_null);
 118   allocator()->Init(common_flags()->allocator_release_to_os_interval_ms);
 119   max_user_defined_malloc_size = common_flags()->max_allocation_size_mb
 120                                      ? common_flags()->max_allocation_size_mb
 121                                            << 20
 122                                      : kMaxAllowedMallocSize;
 123 }
 124
 125 void InitializeAllocatorLate() {
 126   new(global_proc()) GlobalProc();
 127 }
 128
 129 void AllocatorProcStart(Processor *proc) {
 130   allocator()->InitCache(&proc->alloc_cache);
 131   internal_allocator()->InitCache(&proc->internal_alloc_cache);
 132 }
 133
 134 void AllocatorProcFinish(Processor *proc) {
 135   allocator()->DestroyCache(&proc->alloc_cache);
 136   internal_allocator()->DestroyCache(&proc->internal_alloc_cache);
 137 }
 138
 139 void AllocatorPrintStats() {
 140   allocator()->PrintStats();
 141 }
 142
 143 static void SignalUnsafeCall(ThreadState *thr, uptr pc) {
 144   if (atomic_load_relaxed(&thr->in_signal_handler) == 0 ||
 145       !ShouldReport(thr, ReportTypeSignalUnsafe))
 146     return;
 147   VarSizeStackTrace stack;
 148   ObtainCurrentStack(thr, pc, &stack);
 149   if (IsFiredSuppression(ctx, ReportTypeSignalUnsafe, stack))
 150     return;
 151   ThreadRegistryLock l(&ctx->thread_registry);
 152   ScopedReport rep(ReportTypeSignalUnsafe);
 153   rep.AddStack(stack, true);
 154   OutputReport(thr, rep);
 155 }
 156
 157
 158 void *user_alloc_internal(ThreadState *thr, uptr pc, uptr sz, uptr align,
 159                           bool signal) {
 160   if (sz >= kMaxAllowedMallocSize || align >= kMaxAllowedMallocSize ||
 161       sz > max_user_defined_malloc_size) {
 162     if (AllocatorMayReturnNull())
 163       return nullptr;
 164     uptr malloc_limit =
 165         Min(kMaxAllowedMallocSize, max_user_defined_malloc_size);
 166     GET_STACK_TRACE_FATAL(thr, pc);
 167     ReportAllocationSizeTooBig(sz, malloc_limit, &stack);
 168   }
 169   void *p = allocator()->Allocate(&thr->proc()->alloc_cache, sz, align);
 170   if (UNLIKELY(!p)) {
 171     SetAllocatorOutOfMemory();
 172     if (AllocatorMayReturnNull())
 173       return nullptr;
 174     GET_STACK_TRACE_FATAL(thr, pc);
 175     ReportOutOfMemory(sz, &stack);
 176   }
 177   if (ctx && ctx->initialized)
 178     OnUserAlloc(thr, pc, (uptr)p, sz, true);
 179   if (signal)
 180     SignalUnsafeCall(thr, pc);
 181   return p;
 182 }
 183
 184 void user_free(ThreadState *thr, uptr pc, void *p, bool signal) {
 185   ScopedGlobalProcessor sgp;
 186   if (ctx && ctx->initialized)
 187     OnUserFree(thr, pc, (uptr)p, true);
 188   allocator()->Deallocate(&thr->proc()->alloc_cache, p);
 189   if (signal)
 190     SignalUnsafeCall(thr, pc);
 191 }
 192
 193 void *user_alloc(ThreadState *thr, uptr pc, uptr sz) {
 194   return SetErrnoOnNull(user_alloc_internal(thr, pc, sz, kDefaultAlignment));
 195 }
 196
 197 void *user_calloc(ThreadState *thr, uptr pc, uptr size, uptr n) {
 198   if (UNLIKELY(CheckForCallocOverflow(size, n))) {
 199     if (AllocatorMayReturnNull())
 200       return SetErrnoOnNull(nullptr);
 201     GET_STACK_TRACE_FATAL(thr, pc);
 202     ReportCallocOverflow(n, size, &stack);
 203   }
 204   void *p = user_alloc_internal(thr, pc, n * size);
 205   if (p)
 206     internal_memset(p, 0, n * size);
 207   return SetErrnoOnNull(p);
 208 }
 209
 210 void *user_reallocarray(ThreadState *thr, uptr pc, void *p, uptr size, uptr n) {
 211   if (UNLIKELY(CheckForCallocOverflow(size, n))) {
 212     if (AllocatorMayReturnNull())
 213       return SetErrnoOnNull(nullptr);
 214     GET_STACK_TRACE_FATAL(thr, pc);
 215     ReportReallocArrayOverflow(size, n, &stack);
 216   }
 217   return user_realloc(thr, pc, p, size * n);
 218 }
 219
 220 void OnUserAlloc(ThreadState *thr, uptr pc, uptr p, uptr sz, bool write) {
 221   DPrintf("#%d: alloc(%zu) = 0x%zx\n", thr->tid, sz, p);
 222   ctx->metamap.AllocBlock(thr, pc, p, sz);
 223   if (write && thr->ignore_reads_and_writes == 0)
 224     MemoryRangeImitateWrite(thr, pc, (uptr)p, sz);
 225   else
 226     MemoryResetRange(thr, pc, (uptr)p, sz);
 227 }
 228
 229 void OnUserFree(ThreadState *thr, uptr pc, uptr p, bool write) {
 230   CHECK_NE(p, (void*)0);
 231   uptr sz = ctx->metamap.FreeBlock(thr->proc(), p);
 232   DPrintf("#%d: free(0x%zx, %zu)\n", thr->tid, p, sz);
 233   if (write && thr->ignore_reads_and_writes == 0)
 234     MemoryRangeFreed(thr, pc, (uptr)p, sz);
 235 }
 236
 237 void *user_realloc(ThreadState *thr, uptr pc, void *p, uptr sz) {
 238   // FIXME: Handle "shrinking" more efficiently,
 239   // it seems that some software actually does this.
 240   if (!p)
 241     return SetErrnoOnNull(user_alloc_internal(thr, pc, sz));
 242   if (!sz) {
 243     user_free(thr, pc, p);
 244     return nullptr;
 245   }
 246   void *new_p = user_alloc_internal(thr, pc, sz);
 247   if (new_p) {
 248     uptr old_sz = user_alloc_usable_size(p);
 249     internal_memcpy(new_p, p, min(old_sz, sz));
 250     user_free(thr, pc, p);
 251   }
 252   return SetErrnoOnNull(new_p);
 253 }
 254
 255 void *user_memalign(ThreadState *thr, uptr pc, uptr align, uptr sz) {
 256   if (UNLIKELY(!IsPowerOfTwo(align))) {
 257     errno = errno_EINVAL;
 258     if (AllocatorMayReturnNull())
 259       return nullptr;
 260     GET_STACK_TRACE_FATAL(thr, pc);
 261     ReportInvalidAllocationAlignment(align, &stack);
 262   }
 263   return SetErrnoOnNull(user_alloc_internal(thr, pc, sz, align));
 264 }
 265
 266 int user_posix_memalign(ThreadState *thr, uptr pc, void **memptr, uptr align,
 267                         uptr sz) {
 268   if (UNLIKELY(!CheckPosixMemalignAlignment(align))) {
 269     if (AllocatorMayReturnNull())
 270       return errno_EINVAL;
 271     GET_STACK_TRACE_FATAL(thr, pc);
 272     ReportInvalidPosixMemalignAlignment(align, &stack);
 273   }
 274   void *ptr = user_alloc_internal(thr, pc, sz, align);
 275   if (UNLIKELY(!ptr))
 276     // OOM error is already taken care of by user_alloc_internal.
 277     return errno_ENOMEM;
 278   CHECK(IsAligned((uptr)ptr, align));
 279   *memptr = ptr;
 280   return 0;
 281 }
 282
 283 void *user_aligned_alloc(ThreadState *thr, uptr pc, uptr align, uptr sz) {
 284   if (UNLIKELY(!CheckAlignedAllocAlignmentAndSize(align, sz))) {
 285     errno = errno_EINVAL;
 286     if (AllocatorMayReturnNull())
 287       return nullptr;
 288     GET_STACK_TRACE_FATAL(thr, pc);
 289     ReportInvalidAlignedAllocAlignment(sz, align, &stack);
 290   }
 291   return SetErrnoOnNull(user_alloc_internal(thr, pc, sz, align));
 292 }
 293
 294 void *user_valloc(ThreadState *thr, uptr pc, uptr sz) {
 295   return SetErrnoOnNull(user_alloc_internal(thr, pc, sz, GetPageSizeCached()));
 296 }
 297
 298 void *user_pvalloc(ThreadState *thr, uptr pc, uptr sz) {
 299   uptr PageSize = GetPageSizeCached();
 300   if (UNLIKELY(CheckForPvallocOverflow(sz, PageSize))) {
 301     errno = errno_ENOMEM;
 302     if (AllocatorMayReturnNull())
 303       return nullptr;
 304     GET_STACK_TRACE_FATAL(thr, pc);
 305     ReportPvallocOverflow(sz, &stack);
 306   }
 307   // pvalloc(0) should allocate one page.
 308   sz = sz ? RoundUpTo(sz, PageSize) : PageSize;
 309   return SetErrnoOnNull(user_alloc_internal(thr, pc, sz, PageSize));
 310 }
 311
 312 uptr user_alloc_usable_size(const void *p) {
 313   if (p == 0)
 314     return 0;
 315   MBlock *b = ctx->metamap.GetBlock((uptr)p);
 316   if (!b)
 317     return 0;  // Not a valid pointer.
 318   if (b->siz == 0)
 319     return 1;  // Zero-sized allocations are actually 1 byte.
 320   return b->siz;
 321 }
 322
 323 void invoke_malloc_hook(void *ptr, uptr size) {
 324   ThreadState *thr = cur_thread();
 325   if (ctx == 0 || !ctx->initialized || thr->ignore_interceptors)
 326     return;
 327   __sanitizer_malloc_hook(ptr, size);
 328   RunMallocHooks(ptr, size);
 329 }
 330
 331 void invoke_free_hook(void *ptr) {
 332   ThreadState *thr = cur_thread();
 333   if (ctx == 0 || !ctx->initialized || thr->ignore_interceptors)
 334     return;
 335   __sanitizer_free_hook(ptr);
 336   RunFreeHooks(ptr);
 337 }
 338
 339 void *Alloc(uptr sz) {
 340   ThreadState *thr = cur_thread();
 341   if (thr->nomalloc) {
 342     thr->nomalloc = 0;  // CHECK calls internal_malloc().
 343     CHECK(0);
 344   }
 345   return InternalAlloc(sz, &thr->proc()->internal_alloc_cache);
 346 }
 347
 348 void FreeImpl(void *p) {
 349   ThreadState *thr = cur_thread();
 350   if (thr->nomalloc) {
 351     thr->nomalloc = 0;  // CHECK calls internal_malloc().
 352     CHECK(0);
 353   }
 354   InternalFree(p, &thr->proc()->internal_alloc_cache);
 355 }
 356
 357 }  // namespace __tsan
 358
 359 using namespace __tsan;
 360
 361 extern "C" {
 362 uptr __sanitizer_get_current_allocated_bytes() {
 363   uptr stats[AllocatorStatCount];
 364   allocator()->GetStats(stats);
 365   return stats[AllocatorStatAllocated];
 366 }
 367
 368 uptr __sanitizer_get_heap_size() {
 369   uptr stats[AllocatorStatCount];
 370   allocator()->GetStats(stats);
 371   return stats[AllocatorStatMapped];
 372 }
 373
 374 uptr __sanitizer_get_free_bytes() {
 375   return 1;
 376 }
 377
 378 uptr __sanitizer_get_unmapped_bytes() {
 379   return 1;
 380 }
 381
 382 uptr __sanitizer_get_estimated_allocated_size(uptr size) {
 383   return size;
 384 }
 385
 386 int __sanitizer_get_ownership(const void *p) {
 387   return allocator()->GetBlockBegin(p) != 0;
 388 }
 389
 390 uptr __sanitizer_get_allocated_size(const void *p) {
 391   return user_alloc_usable_size(p);
 392 }
 393
 394 void __tsan_on_thread_idle() {
 395   ThreadState *thr = cur_thread();
 396   thr->clock.ResetCached(&thr->proc()->clock_cache);
 397   thr->last_sleep_clock.ResetCached(&thr->proc()->clock_cache);
 398   allocator()->SwallowCache(&thr->proc()->alloc_cache);
 399   internal_allocator()->SwallowCache(&thr->proc()->internal_alloc_cache);
 400   ctx->metamap.OnProcIdle(thr->proc());
 401 }
 402 }  // extern "C"