xref: /freebsd/contrib/llvm-project/compiler-rt/lib/sanitizer_common/symbolizer/sanitizer_symbolize.cpp (revision 13ec1e3155c7e9bf037b12af186351b7fa9b9450)
1 //===-- sanitizer_symbolize.cpp ---------------------------------*- C++ -*-===//
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 // Implementation of weak hooks from sanitizer_symbolizer_posix_libcdep.cpp.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #include <stdio.h>
14 
15 #include <string>
16 
17 #include "llvm/DebugInfo/Symbolize/DIPrinter.h"
18 #include "llvm/DebugInfo/Symbolize/Symbolize.h"
19 
20 static llvm::symbolize::LLVMSymbolizer *getDefaultSymbolizer() {
21   static llvm::symbolize::LLVMSymbolizer *DefaultSymbolizer =
22       new llvm::symbolize::LLVMSymbolizer();
23   return DefaultSymbolizer;
24 }
25 
26 static llvm::symbolize::PrinterConfig getDefaultPrinterConfig() {
27   llvm::symbolize::PrinterConfig Config;
28   Config.Pretty = false;
29   Config.Verbose = false;
30   Config.PrintFunctions = true;
31   Config.PrintAddress = false;
32   Config.SourceContextLines = 0;
33   return Config;
34 }
35 
36 namespace __sanitizer {
37 int internal_snprintf(char *buffer, unsigned long length, const char *format,
38                       ...);
39 }  // namespace __sanitizer
40 
41 extern "C" {
42 
43 typedef uint64_t u64;
44 
45 bool __sanitizer_symbolize_code(const char *ModuleName, uint64_t ModuleOffset,
46                                 char *Buffer, int MaxLength,
47                                 bool SymbolizeInlineFrames) {
48   std::string Result;
49   {
50     llvm::raw_string_ostream OS(Result);
51     llvm::symbolize::PrinterConfig Config = getDefaultPrinterConfig();
52     llvm::symbolize::Request Request{ModuleName, ModuleOffset};
53     auto Printer =
54         std::make_unique<llvm::symbolize::LLVMPrinter>(OS, OS, Config);
55 
56     // TODO: it is neccessary to set proper SectionIndex here.
57     // object::SectionedAddress::UndefSection works for only absolute addresses.
58     if (SymbolizeInlineFrames) {
59       auto ResOrErr = getDefaultSymbolizer()->symbolizeInlinedCode(
60           ModuleName,
61           {ModuleOffset, llvm::object::SectionedAddress::UndefSection});
62       Printer->print(Request,
63                      ResOrErr ? ResOrErr.get() : llvm::DIInliningInfo());
64     } else {
65       auto ResOrErr = getDefaultSymbolizer()->symbolizeCode(
66           ModuleName,
67           {ModuleOffset, llvm::object::SectionedAddress::UndefSection});
68       Printer->print(Request, ResOrErr ? ResOrErr.get() : llvm::DILineInfo());
69     }
70   }
71   return __sanitizer::internal_snprintf(Buffer, MaxLength, "%s",
72                                         Result.c_str()) < MaxLength;
73 }
74 
75 bool __sanitizer_symbolize_data(const char *ModuleName, uint64_t ModuleOffset,
76                                 char *Buffer, int MaxLength) {
77   std::string Result;
78   {
79     llvm::symbolize::PrinterConfig Config = getDefaultPrinterConfig();
80     llvm::raw_string_ostream OS(Result);
81     llvm::symbolize::Request Request{ModuleName, ModuleOffset};
82     auto Printer =
83         std::make_unique<llvm::symbolize::LLVMPrinter>(OS, OS, Config);
84 
85     // TODO: it is neccessary to set proper SectionIndex here.
86     // object::SectionedAddress::UndefSection works for only absolute addresses.
87     auto ResOrErr = getDefaultSymbolizer()->symbolizeData(
88         ModuleName,
89         {ModuleOffset, llvm::object::SectionedAddress::UndefSection});
90     Printer->print(Request, ResOrErr ? ResOrErr.get() : llvm::DIGlobal());
91   }
92   return __sanitizer::internal_snprintf(Buffer, MaxLength, "%s",
93                                         Result.c_str()) < MaxLength;
94 }
95 
96 void __sanitizer_symbolize_flush() { getDefaultSymbolizer()->flush(); }
97 
98 int __sanitizer_symbolize_demangle(const char *Name, char *Buffer,
99                                    int MaxLength) {
100   std::string Result =
101       llvm::symbolize::LLVMSymbolizer::DemangleName(Name, nullptr);
102   return __sanitizer::internal_snprintf(Buffer, MaxLength, "%s",
103                                         Result.c_str()) < MaxLength
104              ? static_cast<int>(Result.size() + 1)
105              : 0;
106 }
107 
108 // Override __cxa_atexit and ignore callbacks.
109 // This prevents crashes in a configuration when the symbolizer
110 // is built into sanitizer runtime and consequently into the test process.
111 // LLVM libraries have some global objects destroyed during exit,
112 // so if the test process triggers any bugs after that, the symbolizer crashes.
113 // An example stack trace of such crash:
114 //
115 // #1  __cxa_throw
116 // #2  std::__u::__throw_system_error
117 // #3  std::__u::recursive_mutex::lock
118 // #4  __sanitizer_llvm::ManagedStaticBase::RegisterManagedStatic
119 // #5  __sanitizer_llvm::errorToErrorCode
120 // #6  __sanitizer_llvm::getFileAux
121 // #7  __sanitizer_llvm::MemoryBuffer::getFileOrSTDIN
122 // #10 __sanitizer_llvm::symbolize::LLVMSymbolizer::getOrCreateModuleInfo
123 // #13 __sanitizer::Symbolizer::SymbolizeData
124 // #14 __tsan::SymbolizeData
125 // #16 __tsan::ReportRace
126 // #18 __tsan_write4
127 // #19 race() () at test/tsan/atexit4.cpp
128 // #20 cxa_at_exit_wrapper
129 // #21 __cxa_finalize
130 // #22 __do_fini
131 //
132 // For the standalone llvm-symbolizer this does not hurt,
133 // we just don't destroy few global objects on exit.
134 int __cxa_atexit(void (*f)(void *a), void *arg, void *dso) { return 0; }
135 
136 }  // extern "C"
137