1 //===-- sanitizer_symbolizer_mac.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 shared between various sanitizers' runtime libraries.
10 //
11 // Implementation of Mac-specific "atos" symbolizer.
12 //===----------------------------------------------------------------------===//
13
14 #include "sanitizer_platform.h"
15 #if SANITIZER_MAC
16
17 #include "sanitizer_allocator_internal.h"
18 #include "sanitizer_mac.h"
19 #include "sanitizer_symbolizer_mac.h"
20
21 #include <dlfcn.h>
22 #include <errno.h>
23 #include <stdlib.h>
24 #include <sys/wait.h>
25 #include <unistd.h>
26 #include <util.h>
27
28 namespace __sanitizer {
29
SymbolizePC(uptr addr,SymbolizedStack * stack)30 bool DlAddrSymbolizer::SymbolizePC(uptr addr, SymbolizedStack *stack) {
31 Dl_info info;
32 int result = dladdr((const void *)addr, &info);
33 if (!result) return false;
34
35 CHECK(addr >= reinterpret_cast<uptr>(info.dli_saddr));
36 stack->info.function_offset = addr - reinterpret_cast<uptr>(info.dli_saddr);
37 const char *demangled = DemangleSwiftAndCXX(info.dli_sname);
38 if (!demangled) return false;
39 stack->info.function = internal_strdup(demangled);
40 return true;
41 }
42
SymbolizeData(uptr addr,DataInfo * datainfo)43 bool DlAddrSymbolizer::SymbolizeData(uptr addr, DataInfo *datainfo) {
44 Dl_info info;
45 int result = dladdr((const void *)addr, &info);
46 if (!result) return false;
47 const char *demangled = DemangleSwiftAndCXX(info.dli_sname);
48 datainfo->name = internal_strdup(demangled);
49 datainfo->start = (uptr)info.dli_saddr;
50 return true;
51 }
52
53 class AtosSymbolizerProcess : public SymbolizerProcess {
54 public:
AtosSymbolizerProcess(const char * path,pid_t parent_pid)55 explicit AtosSymbolizerProcess(const char *path, pid_t parent_pid)
56 : SymbolizerProcess(path, /*use_posix_spawn*/ true) {
57 // Put the string command line argument in the object so that it outlives
58 // the call to GetArgV.
59 internal_snprintf(pid_str_, sizeof(pid_str_), "%d", parent_pid);
60 }
61
62 private:
StartSymbolizerSubprocess()63 bool StartSymbolizerSubprocess() override {
64 // Configure sandbox before starting atos process.
65 return SymbolizerProcess::StartSymbolizerSubprocess();
66 }
67
ReachedEndOfOutput(const char * buffer,uptr length) const68 bool ReachedEndOfOutput(const char *buffer, uptr length) const override {
69 return (length >= 1 && buffer[length - 1] == '\n');
70 }
71
GetArgV(const char * path_to_binary,const char * (& argv)[kArgVMax]) const72 void GetArgV(const char *path_to_binary,
73 const char *(&argv)[kArgVMax]) const override {
74 int i = 0;
75 argv[i++] = path_to_binary;
76 argv[i++] = "-p";
77 argv[i++] = &pid_str_[0];
78 if (GetMacosVersion() == MACOS_VERSION_MAVERICKS) {
79 // On Mavericks atos prints a deprecation warning which we suppress by
80 // passing -d. The warning isn't present on other OSX versions, even the
81 // newer ones.
82 argv[i++] = "-d";
83 }
84 argv[i++] = nullptr;
85 }
86
87 char pid_str_[16];
88 };
89
ParseCommandOutput(const char * str,uptr addr,char ** out_name,char ** out_module,char ** out_file,uptr * line,uptr * start_address)90 static bool ParseCommandOutput(const char *str, uptr addr, char **out_name,
91 char **out_module, char **out_file, uptr *line,
92 uptr *start_address) {
93 // Trim ending newlines.
94 char *trim;
95 ExtractTokenUpToDelimiter(str, "\n", &trim);
96
97 // The line from `atos` is in one of these formats:
98 // myfunction (in library.dylib) (sourcefile.c:17)
99 // myfunction (in library.dylib) + 0x1fe
100 // myfunction (in library.dylib) + 15
101 // 0xdeadbeef (in library.dylib) + 0x1fe
102 // 0xdeadbeef (in library.dylib) + 15
103 // 0xdeadbeef (in library.dylib)
104 // 0xdeadbeef
105
106 const char *rest = trim;
107 char *symbol_name;
108 rest = ExtractTokenUpToDelimiter(rest, " (in ", &symbol_name);
109 if (rest[0] == '\0') {
110 InternalFree(symbol_name);
111 InternalFree(trim);
112 return false;
113 }
114
115 if (internal_strncmp(symbol_name, "0x", 2) != 0)
116 *out_name = symbol_name;
117 else
118 InternalFree(symbol_name);
119 rest = ExtractTokenUpToDelimiter(rest, ") ", out_module);
120
121 if (rest[0] == '(') {
122 if (out_file) {
123 rest++;
124 rest = ExtractTokenUpToDelimiter(rest, ":", out_file);
125 char *extracted_line_number;
126 rest = ExtractTokenUpToDelimiter(rest, ")", &extracted_line_number);
127 if (line) *line = (uptr)internal_atoll(extracted_line_number);
128 InternalFree(extracted_line_number);
129 }
130 } else if (rest[0] == '+') {
131 rest += 2;
132 uptr offset = internal_atoll(rest);
133 if (start_address) *start_address = addr - offset;
134 }
135
136 InternalFree(trim);
137 return true;
138 }
139
AtosSymbolizer(const char * path,LowLevelAllocator * allocator)140 AtosSymbolizer::AtosSymbolizer(const char *path, LowLevelAllocator *allocator)
141 : process_(new(*allocator) AtosSymbolizerProcess(path, getpid())) {}
142
SymbolizePC(uptr addr,SymbolizedStack * stack)143 bool AtosSymbolizer::SymbolizePC(uptr addr, SymbolizedStack *stack) {
144 if (!process_) return false;
145 if (addr == 0) return false;
146 char command[32];
147 internal_snprintf(command, sizeof(command), "0x%zx\n", addr);
148 const char *buf = process_->SendCommand(command);
149 if (!buf) return false;
150 uptr line;
151 uptr start_address = AddressInfo::kUnknown;
152 if (!ParseCommandOutput(buf, addr, &stack->info.function, &stack->info.module,
153 &stack->info.file, &line, &start_address)) {
154 process_ = nullptr;
155 return false;
156 }
157 stack->info.line = (int)line;
158
159 if (start_address == AddressInfo::kUnknown) {
160 // Fallback to dladdr() to get function start address if atos doesn't report
161 // it.
162 Dl_info info;
163 int result = dladdr((const void *)addr, &info);
164 if (result)
165 start_address = reinterpret_cast<uptr>(info.dli_saddr);
166 }
167
168 // Only assig to `function_offset` if we were able to get the function's
169 // start address.
170 if (start_address != AddressInfo::kUnknown) {
171 CHECK(addr >= start_address);
172 stack->info.function_offset = addr - start_address;
173 }
174 return true;
175 }
176
SymbolizeData(uptr addr,DataInfo * info)177 bool AtosSymbolizer::SymbolizeData(uptr addr, DataInfo *info) {
178 if (!process_) return false;
179 char command[32];
180 internal_snprintf(command, sizeof(command), "0x%zx\n", addr);
181 const char *buf = process_->SendCommand(command);
182 if (!buf) return false;
183 if (!ParseCommandOutput(buf, addr, &info->name, &info->module, nullptr,
184 nullptr, &info->start)) {
185 process_ = nullptr;
186 return false;
187 }
188 return true;
189 }
190
191 } // namespace __sanitizer
192
193 #endif // SANITIZER_MAC
194