compiler-rt/lib/lsan/lsan_posix.cpp

   1 //=-- lsan_posix.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 LeakSanitizer.
  10 // Standalone LSan RTL code common to POSIX-like systems.
  11 //
  12 //===---------------------------------------------------------------------===//
  13
  14 #include "sanitizer_common/sanitizer_platform.h"
  15
  16 #if SANITIZER_POSIX
  17 #  include <pthread.h>
  18
  19 #  include "lsan.h"
  20 #  include "lsan_allocator.h"
  21 #  include "lsan_thread.h"
  22 #  include "sanitizer_common/sanitizer_stacktrace.h"
  23 #  include "sanitizer_common/sanitizer_tls_get_addr.h"
  24
  25 namespace __lsan {
  26
  27 ThreadContext::ThreadContext(int tid) : ThreadContextLsanBase(tid) {}
  28
  29 struct OnStartedArgs {
  30   uptr stack_begin;
  31   uptr stack_end;
  32   uptr cache_begin;
  33   uptr cache_end;
  34   uptr tls_begin;
  35   uptr tls_end;
  36   DTLS *dtls;
  37 };
  38
  39 void ThreadContext::OnStarted(void *arg) {
  40   ThreadContextLsanBase::OnStarted(arg);
  41   auto args = reinterpret_cast<const OnStartedArgs *>(arg);
  42   stack_begin_ = args->stack_begin;
  43   stack_end_ = args->stack_end;
  44   tls_begin_ = args->tls_begin;
  45   tls_end_ = args->tls_end;
  46   cache_begin_ = args->cache_begin;
  47   cache_end_ = args->cache_end;
  48   dtls_ = args->dtls;
  49 }
  50
  51 void ThreadStart(u32 tid, tid_t os_id, ThreadType thread_type) {
  52   OnStartedArgs args;
  53   GetThreadStackAndTls(tid == kMainTid, &args.stack_begin, &args.stack_end,
  54                        &args.tls_begin, &args.tls_end);
  55   GetAllocatorCacheRange(&args.cache_begin, &args.cache_end);
  56   args.dtls = DTLS_Get();
  57   ThreadContextLsanBase::ThreadStart(tid, os_id, thread_type, &args);
  58 }
  59
  60 bool GetThreadRangesLocked(tid_t os_id, uptr *stack_begin, uptr *stack_end,
  61                            uptr *tls_begin, uptr *tls_end, uptr *cache_begin,
  62                            uptr *cache_end, DTLS **dtls) {
  63   ThreadContext *context = static_cast<ThreadContext *>(
  64       GetLsanThreadRegistryLocked()->FindThreadContextByOsIDLocked(os_id));
  65   if (!context)
  66     return false;
  67   *stack_begin = context->stack_begin();
  68   *stack_end = context->stack_end();
  69   *tls_begin = context->tls_begin();
  70   *tls_end = context->tls_end();
  71   *cache_begin = context->cache_begin();
  72   *cache_end = context->cache_end();
  73   *dtls = context->dtls();
  74   return true;
  75 }
  76
  77 void InitializeMainThread() {
  78   u32 tid = ThreadCreate(kMainTid, true);
  79   CHECK_EQ(tid, kMainTid);
  80   ThreadStart(tid, GetTid());
  81 }
  82
  83 static void OnStackUnwind(const SignalContext &sig, const void *,
  84                           BufferedStackTrace *stack) {
  85   stack->Unwind(StackTrace::GetNextInstructionPc(sig.pc), sig.bp, sig.context,
  86                 common_flags()->fast_unwind_on_fatal);
  87 }
  88
  89 void LsanOnDeadlySignal(int signo, void *siginfo, void *context) {
  90   HandleDeadlySignal(siginfo, context, GetCurrentThreadId(), &OnStackUnwind,
  91                      nullptr);
  92 }
  93
  94 void InstallAtExitCheckLeaks() {
  95   if (common_flags()->detect_leaks && common_flags()->leak_check_at_exit)
  96     Atexit(DoLeakCheck);
  97 }
  98
  99 static void BeforeFork() {
 100   VReport(2, "BeforeFork tid: %llu\n", GetTid());
 101   LockGlobal();
 102   LockThreads();
 103   LockAllocator();
 104   StackDepotLockBeforeFork();
 105 }
 106
 107 static void AfterFork(bool fork_child) {
 108   StackDepotUnlockAfterFork(fork_child);
 109   UnlockAllocator();
 110   UnlockThreads();
 111   UnlockGlobal();
 112   VReport(2, "AfterFork tid: %llu\n", GetTid());
 113 }
 114
 115 void InstallAtForkHandler() {
 116 #  if SANITIZER_SOLARIS || SANITIZER_NETBSD || SANITIZER_APPLE
 117   return;  // FIXME: Implement FutexWait.
 118 #  endif
 119   pthread_atfork(
 120       &BeforeFork, []() { AfterFork(/* fork_child= */ false); },
 121       []() { AfterFork(/* fork_child= */ true); });
 122 }
 123
 124 }  // namespace __lsan
 125
 126 #endif  // SANITIZER_POSIX