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
25namespace __lsan {
26
27ThreadContext::ThreadContext(int tid) : ThreadContextLsanBase(tid) {}
28
29struct 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
39void 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
51void ThreadStart(u32 tid, tid_t os_id, ThreadType thread_type) {
52 OnStartedArgs args;
53 GetThreadStackAndTls(main: tid == kMainTid, stk_begin: &args.stack_begin, stk_end: &args.stack_end,
54 tls_begin: &args.tls_begin, tls_end: &args.tls_end);
55 GetAllocatorCacheRange(begin: &args.cache_begin, end: &args.cache_end);
56 args.dtls = DTLS_Get();
57 ThreadContextLsanBase::ThreadStart(tid, os_id, thread_type, onstarted_arg: &args);
58}
59
60bool 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
77void InitializeMainThread() {
78 u32 tid = ThreadCreate(tid: kMainTid, detached: true);
79 CHECK_EQ(tid, kMainTid);
80 ThreadStart(tid, os_id: GetTid());
81}
82
83static void OnStackUnwind(const SignalContext &sig, const void *,
84 BufferedStackTrace *stack) {
85 stack->Unwind(pc: StackTrace::GetNextInstructionPc(pc: sig.pc), bp: sig.bp, context: sig.context,
86 request_fast: common_flags()->fast_unwind_on_fatal);
87}
88
89void LsanOnDeadlySignal(int signo, void *siginfo, void *context) {
90 HandleDeadlySignal(siginfo, context, tid: GetCurrentThreadId(), unwind: &OnStackUnwind,
91 unwind_context: nullptr);
92}
93
94void InstallAtExitCheckLeaks() {
95 if (common_flags()->detect_leaks && common_flags()->leak_check_at_exit)
96 Atexit(function: DoLeakCheck);
97}
98
99static void BeforeFork() {
100 VReport(2, "BeforeFork tid: %llu\n", GetTid());
101 LockGlobal();
102 LockThreads();
103 LockAllocator();
104 StackDepotLockBeforeFork();
105}
106
107static 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
115void InstallAtForkHandler() {
116# if SANITIZER_SOLARIS || SANITIZER_NETBSD || SANITIZER_APPLE
117 return; // FIXME: Implement FutexWait.
118# endif
119 pthread_atfork(
120 prepare: &BeforeFork, parent: []() { AfterFork(/* fork_child= */ false); },
121 child: []() { AfterFork(/* fork_child= */ true); });
122}
123
124} // namespace __lsan
125
126#endif // SANITIZER_POSIX
127