1 //===-- InstrumentationRuntimeASan.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 #include "InstrumentationRuntimeASan.h"
10 
11 #include "lldb/Breakpoint/StoppointCallbackContext.h"
12 #include "lldb/Core/Debugger.h"
13 #include "lldb/Core/Module.h"
14 #include "lldb/Core/PluginInterface.h"
15 #include "lldb/Core/PluginManager.h"
16 #include "lldb/Core/StreamFile.h"
17 #include "lldb/Core/ValueObject.h"
18 #include "lldb/Expression/UserExpression.h"
19 #include "lldb/Interpreter/CommandReturnObject.h"
20 #include "lldb/Symbol/Symbol.h"
21 #include "lldb/Target/InstrumentationRuntimeStopInfo.h"
22 #include "lldb/Target/StopInfo.h"
23 #include "lldb/Target/Target.h"
24 #include "lldb/Target/Thread.h"
25 #include "lldb/Utility/RegularExpression.h"
26 #include "lldb/Utility/Stream.h"
27 
28 #include "llvm/ADT/StringSwitch.h"
29 
30 using namespace lldb;
31 using namespace lldb_private;
32 
33 LLDB_PLUGIN_DEFINE(InstrumentationRuntimeASan)
34 
35 lldb::InstrumentationRuntimeSP
36 InstrumentationRuntimeASan::CreateInstance(const lldb::ProcessSP &process_sp) {
37   return InstrumentationRuntimeSP(new InstrumentationRuntimeASan(process_sp));
38 }
39 
40 void InstrumentationRuntimeASan::Initialize() {
41   PluginManager::RegisterPlugin(
42       GetPluginNameStatic(), "AddressSanitizer instrumentation runtime plugin.",
43       CreateInstance, GetTypeStatic);
44 }
45 
46 void InstrumentationRuntimeASan::Terminate() {
47   PluginManager::UnregisterPlugin(CreateInstance);
48 }
49 
50 lldb::InstrumentationRuntimeType InstrumentationRuntimeASan::GetTypeStatic() {
51   return eInstrumentationRuntimeTypeAddressSanitizer;
52 }
53 
54 InstrumentationRuntimeASan::~InstrumentationRuntimeASan() { Deactivate(); }
55 
56 const RegularExpression &
57 InstrumentationRuntimeASan::GetPatternForRuntimeLibrary() {
58   // FIXME: This shouldn't include the "dylib" suffix.
59   static RegularExpression regex(
60       llvm::StringRef("libclang_rt.asan_(.*)_dynamic\\.dylib"));
61   return regex;
62 }
63 
64 bool InstrumentationRuntimeASan::CheckIfRuntimeIsValid(
65     const lldb::ModuleSP module_sp) {
66   const Symbol *symbol = module_sp->FindFirstSymbolWithNameAndType(
67       ConstString("__asan_get_alloc_stack"), lldb::eSymbolTypeAny);
68 
69   return symbol != nullptr;
70 }
71 
72 const char *address_sanitizer_retrieve_report_data_prefix = R"(
73 extern "C"
74 {
75 int __asan_report_present();
76 void *__asan_get_report_pc();
77 void *__asan_get_report_bp();
78 void *__asan_get_report_sp();
79 void *__asan_get_report_address();
80 const char *__asan_get_report_description();
81 int __asan_get_report_access_type();
82 size_t __asan_get_report_access_size();
83 }
84 )";
85 
86 const char *address_sanitizer_retrieve_report_data_command = R"(
87 struct {
88     int present;
89     int access_type;
90     void *pc;
91     void *bp;
92     void *sp;
93     void *address;
94     size_t access_size;
95     const char *description;
96 } t;
97 
98 t.present = __asan_report_present();
99 t.access_type = __asan_get_report_access_type();
100 t.pc = __asan_get_report_pc();
101 t.bp = __asan_get_report_bp();
102 t.sp = __asan_get_report_sp();
103 t.address = __asan_get_report_address();
104 t.access_size = __asan_get_report_access_size();
105 t.description = __asan_get_report_description();
106 t
107 )";
108 
109 StructuredData::ObjectSP InstrumentationRuntimeASan::RetrieveReportData() {
110   ProcessSP process_sp = GetProcessSP();
111   if (!process_sp)
112     return StructuredData::ObjectSP();
113 
114   ThreadSP thread_sp =
115       process_sp->GetThreadList().GetExpressionExecutionThread();
116   StackFrameSP frame_sp = thread_sp->GetSelectedFrame();
117 
118   if (!frame_sp)
119     return StructuredData::ObjectSP();
120 
121   EvaluateExpressionOptions options;
122   options.SetUnwindOnError(true);
123   options.SetTryAllThreads(true);
124   options.SetStopOthers(true);
125   options.SetIgnoreBreakpoints(true);
126   options.SetTimeout(process_sp->GetUtilityExpressionTimeout());
127   options.SetPrefix(address_sanitizer_retrieve_report_data_prefix);
128   options.SetAutoApplyFixIts(false);
129   options.SetLanguage(eLanguageTypeObjC_plus_plus);
130 
131   ValueObjectSP return_value_sp;
132   ExecutionContext exe_ctx;
133   Status eval_error;
134   frame_sp->CalculateExecutionContext(exe_ctx);
135   ExpressionResults result = UserExpression::Evaluate(
136       exe_ctx, options, address_sanitizer_retrieve_report_data_command, "",
137       return_value_sp, eval_error);
138   if (result != eExpressionCompleted) {
139     StreamString ss;
140     ss << "cannot evaluate AddressSanitizer expression:\n";
141     ss << eval_error.AsCString();
142     Debugger::ReportWarning(ss.GetString().str(),
143                             process_sp->GetTarget().GetDebugger().GetID());
144     return StructuredData::ObjectSP();
145   }
146 
147   int present = return_value_sp->GetValueForExpressionPath(".present")
148                     ->GetValueAsUnsigned(0);
149   if (present != 1)
150     return StructuredData::ObjectSP();
151 
152   addr_t pc =
153       return_value_sp->GetValueForExpressionPath(".pc")->GetValueAsUnsigned(0);
154   /* commented out because rdar://problem/18533301
155   addr_t bp =
156   return_value_sp->GetValueForExpressionPath(".bp")->GetValueAsUnsigned(0);
157   addr_t sp =
158   return_value_sp->GetValueForExpressionPath(".sp")->GetValueAsUnsigned(0);
159   */
160   addr_t address = return_value_sp->GetValueForExpressionPath(".address")
161                        ->GetValueAsUnsigned(0);
162   addr_t access_type =
163       return_value_sp->GetValueForExpressionPath(".access_type")
164           ->GetValueAsUnsigned(0);
165   addr_t access_size =
166       return_value_sp->GetValueForExpressionPath(".access_size")
167           ->GetValueAsUnsigned(0);
168   addr_t description_ptr =
169       return_value_sp->GetValueForExpressionPath(".description")
170           ->GetValueAsUnsigned(0);
171   std::string description;
172   Status error;
173   process_sp->ReadCStringFromMemory(description_ptr, description, error);
174 
175   StructuredData::Dictionary *dict = new StructuredData::Dictionary();
176   dict->AddStringItem("instrumentation_class", "AddressSanitizer");
177   dict->AddStringItem("stop_type", "fatal_error");
178   dict->AddIntegerItem("pc", pc);
179   /* commented out because rdar://problem/18533301
180   dict->AddIntegerItem("bp", bp);
181   dict->AddIntegerItem("sp", sp);
182   */
183   dict->AddIntegerItem("address", address);
184   dict->AddIntegerItem("access_type", access_type);
185   dict->AddIntegerItem("access_size", access_size);
186   dict->AddStringItem("description", description);
187 
188   return StructuredData::ObjectSP(dict);
189 }
190 
191 std::string
192 InstrumentationRuntimeASan::FormatDescription(StructuredData::ObjectSP report) {
193   std::string description = std::string(report->GetAsDictionary()
194                                             ->GetValueForKey("description")
195                                             ->GetAsString()
196                                             ->GetValue());
197   return llvm::StringSwitch<std::string>(description)
198       .Case("heap-use-after-free", "Use of deallocated memory")
199       .Case("heap-buffer-overflow", "Heap buffer overflow")
200       .Case("stack-buffer-underflow", "Stack buffer underflow")
201       .Case("initialization-order-fiasco", "Initialization order problem")
202       .Case("stack-buffer-overflow", "Stack buffer overflow")
203       .Case("stack-use-after-return", "Use of stack memory after return")
204       .Case("use-after-poison", "Use of poisoned memory")
205       .Case("container-overflow", "Container overflow")
206       .Case("stack-use-after-scope", "Use of out-of-scope stack memory")
207       .Case("global-buffer-overflow", "Global buffer overflow")
208       .Case("unknown-crash", "Invalid memory access")
209       .Case("stack-overflow", "Stack space exhausted")
210       .Case("null-deref", "Dereference of null pointer")
211       .Case("wild-jump", "Jump to non-executable address")
212       .Case("wild-addr-write", "Write through wild pointer")
213       .Case("wild-addr-read", "Read from wild pointer")
214       .Case("wild-addr", "Access through wild pointer")
215       .Case("signal", "Deadly signal")
216       .Case("double-free", "Deallocation of freed memory")
217       .Case("new-delete-type-mismatch",
218             "Deallocation size different from allocation size")
219       .Case("bad-free", "Deallocation of non-allocated memory")
220       .Case("alloc-dealloc-mismatch",
221             "Mismatch between allocation and deallocation APIs")
222       .Case("bad-malloc_usable_size", "Invalid argument to malloc_usable_size")
223       .Case("bad-__sanitizer_get_allocated_size",
224             "Invalid argument to __sanitizer_get_allocated_size")
225       .Case("param-overlap",
226             "Call to function disallowing overlapping memory ranges")
227       .Case("negative-size-param", "Negative size used when accessing memory")
228       .Case("bad-__sanitizer_annotate_contiguous_container",
229             "Invalid argument to __sanitizer_annotate_contiguous_container")
230       .Case("odr-violation", "Symbol defined in multiple translation units")
231       .Case(
232           "invalid-pointer-pair",
233           "Comparison or arithmetic on pointers from different memory regions")
234       // for unknown report codes just show the code
235       .Default("AddressSanitizer detected: " + description);
236 }
237 
238 bool InstrumentationRuntimeASan::NotifyBreakpointHit(
239     void *baton, StoppointCallbackContext *context, user_id_t break_id,
240     user_id_t break_loc_id) {
241   assert(baton && "null baton");
242   if (!baton)
243     return false;
244 
245   InstrumentationRuntimeASan *const instance =
246       static_cast<InstrumentationRuntimeASan *>(baton);
247 
248   ProcessSP process_sp = instance->GetProcessSP();
249 
250   if (process_sp->GetModIDRef().IsLastResumeForUserExpression())
251     return false;
252 
253   StructuredData::ObjectSP report = instance->RetrieveReportData();
254   std::string description;
255   if (report) {
256     description = instance->FormatDescription(report);
257   }
258   // Make sure this is the right process
259   if (process_sp && process_sp == context->exe_ctx_ref.GetProcessSP()) {
260     ThreadSP thread_sp = context->exe_ctx_ref.GetThreadSP();
261     if (thread_sp)
262       thread_sp->SetStopInfo(InstrumentationRuntimeStopInfo::
263                                  CreateStopReasonWithInstrumentationData(
264                                      *thread_sp, description, report));
265 
266     StreamFileSP stream_sp(
267         process_sp->GetTarget().GetDebugger().GetOutputStreamSP());
268     if (stream_sp) {
269       stream_sp->Printf("AddressSanitizer report breakpoint hit. Use 'thread "
270                         "info -s' to get extended information about the "
271                         "report.\n");
272     }
273     return true; // Return true to stop the target
274   } else
275     return false; // Let target run
276 }
277 
278 void InstrumentationRuntimeASan::Activate() {
279   if (IsActive())
280     return;
281 
282   ProcessSP process_sp = GetProcessSP();
283   if (!process_sp)
284     return;
285 
286   ConstString symbol_name("_ZN6__asanL7AsanDieEv");
287   const Symbol *symbol = GetRuntimeModuleSP()->FindFirstSymbolWithNameAndType(
288       symbol_name, eSymbolTypeCode);
289 
290   if (symbol == nullptr)
291     return;
292 
293   if (!symbol->ValueIsAddress() || !symbol->GetAddressRef().IsValid())
294     return;
295 
296   Target &target = process_sp->GetTarget();
297   addr_t symbol_address = symbol->GetAddressRef().GetOpcodeLoadAddress(&target);
298 
299   if (symbol_address == LLDB_INVALID_ADDRESS)
300     return;
301 
302   const bool internal = true;
303   const bool hardware = false;
304   const bool sync = false;
305   Breakpoint *breakpoint =
306       process_sp->GetTarget()
307           .CreateBreakpoint(symbol_address, internal, hardware)
308           .get();
309   breakpoint->SetCallback(InstrumentationRuntimeASan::NotifyBreakpointHit, this,
310                           sync);
311   breakpoint->SetBreakpointKind("address-sanitizer-report");
312   SetBreakpointID(breakpoint->GetID());
313 
314   SetActive(true);
315 }
316 
317 void InstrumentationRuntimeASan::Deactivate() {
318   if (GetBreakpointID() != LLDB_INVALID_BREAK_ID) {
319     ProcessSP process_sp = GetProcessSP();
320     if (process_sp) {
321       process_sp->GetTarget().RemoveBreakpointByID(GetBreakpointID());
322       SetBreakpointID(LLDB_INVALID_BREAK_ID);
323     }
324   }
325   SetActive(false);
326 }
327