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 "sanitizer_common/sanitizer_stacktrace.h"
20 #include "sanitizer_common/sanitizer_tls_get_addr.h"
21 
22 namespace __lsan {
23 
24 ThreadContext::ThreadContext(int tid) : ThreadContextLsanBase(tid) {}
25 
26 struct OnStartedArgs {
27   uptr stack_begin;
28   uptr stack_end;
29   uptr cache_begin;
30   uptr cache_end;
31   uptr tls_begin;
32   uptr tls_end;
33   DTLS *dtls;
34 };
35 
36 void ThreadContext::OnStarted(void *arg) {
37   auto args = reinterpret_cast<const OnStartedArgs *>(arg);
38   stack_begin_ = args->stack_begin;
39   stack_end_ = args->stack_end;
40   tls_begin_ = args->tls_begin;
41   tls_end_ = args->tls_end;
42   cache_begin_ = args->cache_begin;
43   cache_end_ = args->cache_end;
44   dtls_ = args->dtls;
45 }
46 
47 void ThreadStart(u32 tid, tid_t os_id, ThreadType thread_type) {
48   OnStartedArgs args;
49   uptr stack_size = 0;
50   uptr tls_size = 0;
51   GetThreadStackAndTls(tid == kMainTid, &args.stack_begin, &stack_size,
52                        &args.tls_begin, &tls_size);
53   args.stack_end = args.stack_begin + stack_size;
54   args.tls_end = args.tls_begin + tls_size;
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       GetThreadRegistryLocked()->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, GetCurrentThread(), &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 }  // namespace __lsan
100 
101 #endif  // SANITIZER_POSIX
102