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 "lsan.h"
18 #include "lsan_allocator.h"
19 #include "lsan_thread.h"
20 #include "sanitizer_common/sanitizer_stacktrace.h"
21 #include "sanitizer_common/sanitizer_tls_get_addr.h"
22 
23 namespace __lsan {
24 
25 ThreadContext::ThreadContext(int tid) : ThreadContextLsanBase(tid) {}
26 
27 struct OnStartedArgs {
28   uptr stack_begin;
29   uptr stack_end;
30   uptr cache_begin;
31   uptr cache_end;
32   uptr tls_begin;
33   uptr tls_end;
34   DTLS *dtls;
35 };
36 
37 void ThreadContext::OnStarted(void *arg) {
38   ThreadContextLsanBase::OnStarted(arg);
39   auto args = reinterpret_cast<const OnStartedArgs *>(arg);
40   stack_begin_ = args->stack_begin;
41   stack_end_ = args->stack_end;
42   tls_begin_ = args->tls_begin;
43   tls_end_ = args->tls_end;
44   cache_begin_ = args->cache_begin;
45   cache_end_ = args->cache_end;
46   dtls_ = args->dtls;
47 }
48 
49 void ThreadStart(u32 tid, tid_t os_id, ThreadType thread_type) {
50   OnStartedArgs args;
51   uptr stack_size = 0;
52   uptr tls_size = 0;
53   GetThreadStackAndTls(tid == kMainTid, &args.stack_begin, &stack_size,
54                        &args.tls_begin, &tls_size);
55   args.stack_end = args.stack_begin + stack_size;
56   args.tls_end = args.tls_begin + tls_size;
57   GetAllocatorCacheRange(&args.cache_begin, &args.cache_end);
58   args.dtls = DTLS_Get();
59   ThreadContextLsanBase::ThreadStart(tid, os_id, thread_type, &args);
60 }
61 
62 bool GetThreadRangesLocked(tid_t os_id, uptr *stack_begin, uptr *stack_end,
63                            uptr *tls_begin, uptr *tls_end, uptr *cache_begin,
64                            uptr *cache_end, DTLS **dtls) {
65   ThreadContext *context = static_cast<ThreadContext *>(
66       GetLsanThreadRegistryLocked()->FindThreadContextByOsIDLocked(os_id));
67   if (!context)
68     return false;
69   *stack_begin = context->stack_begin();
70   *stack_end = context->stack_end();
71   *tls_begin = context->tls_begin();
72   *tls_end = context->tls_end();
73   *cache_begin = context->cache_begin();
74   *cache_end = context->cache_end();
75   *dtls = context->dtls();
76   return true;
77 }
78 
79 void InitializeMainThread() {
80   u32 tid = ThreadCreate(kMainTid, true);
81   CHECK_EQ(tid, kMainTid);
82   ThreadStart(tid, GetTid());
83 }
84 
85 static void OnStackUnwind(const SignalContext &sig, const void *,
86                           BufferedStackTrace *stack) {
87   stack->Unwind(StackTrace::GetNextInstructionPc(sig.pc), sig.bp, sig.context,
88                 common_flags()->fast_unwind_on_fatal);
89 }
90 
91 void LsanOnDeadlySignal(int signo, void *siginfo, void *context) {
92   HandleDeadlySignal(siginfo, context, GetCurrentThreadId(), &OnStackUnwind,
93                      nullptr);
94 }
95 
96 void InstallAtExitCheckLeaks() {
97   if (common_flags()->detect_leaks && common_flags()->leak_check_at_exit)
98     Atexit(DoLeakCheck);
99 }
100 
101 }  // namespace __lsan
102 
103 #endif  // SANITIZER_POSIX
104