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
ThreadContext(int tid)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
OnStarted(void * arg)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
ThreadStart(u32 tid,tid_t os_id,ThreadType thread_type)51 void ThreadStart(u32 tid, tid_t os_id, ThreadType thread_type) {
52 OnStartedArgs args;
53 uptr stack_size = 0;
54 uptr tls_size = 0;
55 GetThreadStackAndTls(tid == kMainTid, &args.stack_begin, &stack_size,
56 &args.tls_begin, &tls_size);
57 args.stack_end = args.stack_begin + stack_size;
58 args.tls_end = args.tls_begin + tls_size;
59 GetAllocatorCacheRange(&args.cache_begin, &args.cache_end);
60 args.dtls = DTLS_Get();
61 ThreadContextLsanBase::ThreadStart(tid, os_id, thread_type, &args);
62 }
63
GetThreadRangesLocked(tid_t os_id,uptr * stack_begin,uptr * stack_end,uptr * tls_begin,uptr * tls_end,uptr * cache_begin,uptr * cache_end,DTLS ** dtls)64 bool GetThreadRangesLocked(tid_t os_id, uptr *stack_begin, uptr *stack_end,
65 uptr *tls_begin, uptr *tls_end, uptr *cache_begin,
66 uptr *cache_end, DTLS **dtls) {
67 ThreadContext *context = static_cast<ThreadContext *>(
68 GetLsanThreadRegistryLocked()->FindThreadContextByOsIDLocked(os_id));
69 if (!context)
70 return false;
71 *stack_begin = context->stack_begin();
72 *stack_end = context->stack_end();
73 *tls_begin = context->tls_begin();
74 *tls_end = context->tls_end();
75 *cache_begin = context->cache_begin();
76 *cache_end = context->cache_end();
77 *dtls = context->dtls();
78 return true;
79 }
80
InitializeMainThread()81 void InitializeMainThread() {
82 u32 tid = ThreadCreate(kMainTid, true);
83 CHECK_EQ(tid, kMainTid);
84 ThreadStart(tid, GetTid());
85 }
86
OnStackUnwind(const SignalContext & sig,const void *,BufferedStackTrace * stack)87 static void OnStackUnwind(const SignalContext &sig, const void *,
88 BufferedStackTrace *stack) {
89 stack->Unwind(StackTrace::GetNextInstructionPc(sig.pc), sig.bp, sig.context,
90 common_flags()->fast_unwind_on_fatal);
91 }
92
LsanOnDeadlySignal(int signo,void * siginfo,void * context)93 void LsanOnDeadlySignal(int signo, void *siginfo, void *context) {
94 HandleDeadlySignal(siginfo, context, GetCurrentThreadId(), &OnStackUnwind,
95 nullptr);
96 }
97
InstallAtExitCheckLeaks()98 void InstallAtExitCheckLeaks() {
99 if (common_flags()->detect_leaks && common_flags()->leak_check_at_exit)
100 Atexit(DoLeakCheck);
101 }
102
BeforeFork()103 static void BeforeFork() {
104 LockGlobal();
105 LockThreads();
106 LockAllocator();
107 StackDepotLockBeforeFork();
108 }
109
AfterFork(bool fork_child)110 static void AfterFork(bool fork_child) {
111 StackDepotUnlockAfterFork(fork_child);
112 UnlockAllocator();
113 UnlockThreads();
114 UnlockGlobal();
115 }
116
InstallAtForkHandler()117 void InstallAtForkHandler() {
118 # if SANITIZER_SOLARIS || SANITIZER_NETBSD || SANITIZER_APPLE
119 return; // FIXME: Implement FutexWait.
120 # endif
121 pthread_atfork(
122 &BeforeFork, []() { AfterFork(/* fork_child= */ false); },
123 []() { AfterFork(/* fork_child= */ true); });
124 }
125
126 } // namespace __lsan
127
128 #endif // SANITIZER_POSIX
129