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 
LLDB_PLUGIN_DEFINE(InstrumentationRuntimeASan)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 
Initialize()40 void InstrumentationRuntimeASan::Initialize() {
41   PluginManager::RegisterPlugin(
42       GetPluginNameStatic(), "AddressSanitizer instrumentation runtime plugin.",
43       CreateInstance, GetTypeStatic);
44 }
45 
Terminate()46 void InstrumentationRuntimeASan::Terminate() {
47   PluginManager::UnregisterPlugin(CreateInstance);
48 }
49 
GetPluginNameStatic()50 lldb_private::ConstString InstrumentationRuntimeASan::GetPluginNameStatic() {
51   return ConstString("AddressSanitizer");
52 }
53 
GetTypeStatic()54 lldb::InstrumentationRuntimeType InstrumentationRuntimeASan::GetTypeStatic() {
55   return eInstrumentationRuntimeTypeAddressSanitizer;
56 }
57 
~InstrumentationRuntimeASan()58 InstrumentationRuntimeASan::~InstrumentationRuntimeASan() { Deactivate(); }
59 
60 const RegularExpression &
GetPatternForRuntimeLibrary()61 InstrumentationRuntimeASan::GetPatternForRuntimeLibrary() {
62   // FIXME: This shouldn't include the "dylib" suffix.
63   static RegularExpression regex(
64       llvm::StringRef("libclang_rt.asan_(.*)_dynamic\\.dylib"));
65   return regex;
66 }
67 
CheckIfRuntimeIsValid(const lldb::ModuleSP module_sp)68 bool InstrumentationRuntimeASan::CheckIfRuntimeIsValid(
69     const lldb::ModuleSP module_sp) {
70   const Symbol *symbol = module_sp->FindFirstSymbolWithNameAndType(
71       ConstString("__asan_get_alloc_stack"), lldb::eSymbolTypeAny);
72 
73   return symbol != nullptr;
74 }
75 
76 const char *address_sanitizer_retrieve_report_data_prefix = R"(
77 extern "C"
78 {
79 int __asan_report_present();
80 void *__asan_get_report_pc();
81 void *__asan_get_report_bp();
82 void *__asan_get_report_sp();
83 void *__asan_get_report_address();
84 const char *__asan_get_report_description();
85 int __asan_get_report_access_type();
86 size_t __asan_get_report_access_size();
87 }
88 )";
89 
90 const char *address_sanitizer_retrieve_report_data_command = R"(
91 struct {
92     int present;
93     int access_type;
94     void *pc;
95     void *bp;
96     void *sp;
97     void *address;
98     size_t access_size;
99     const char *description;
100 } t;
101 
102 t.present = __asan_report_present();
103 t.access_type = __asan_get_report_access_type();
104 t.pc = __asan_get_report_pc();
105 t.bp = __asan_get_report_bp();
106 t.sp = __asan_get_report_sp();
107 t.address = __asan_get_report_address();
108 t.access_size = __asan_get_report_access_size();
109 t.description = __asan_get_report_description();
110 t
111 )";
112 
RetrieveReportData()113 StructuredData::ObjectSP InstrumentationRuntimeASan::RetrieveReportData() {
114   ProcessSP process_sp = GetProcessSP();
115   if (!process_sp)
116     return StructuredData::ObjectSP();
117 
118   ThreadSP thread_sp =
119       process_sp->GetThreadList().GetExpressionExecutionThread();
120   StackFrameSP frame_sp = thread_sp->GetSelectedFrame();
121 
122   if (!frame_sp)
123     return StructuredData::ObjectSP();
124 
125   EvaluateExpressionOptions options;
126   options.SetUnwindOnError(true);
127   options.SetTryAllThreads(true);
128   options.SetStopOthers(true);
129   options.SetIgnoreBreakpoints(true);
130   options.SetTimeout(process_sp->GetUtilityExpressionTimeout());
131   options.SetPrefix(address_sanitizer_retrieve_report_data_prefix);
132   options.SetAutoApplyFixIts(false);
133   options.SetLanguage(eLanguageTypeObjC_plus_plus);
134 
135   ValueObjectSP return_value_sp;
136   ExecutionContext exe_ctx;
137   Status eval_error;
138   frame_sp->CalculateExecutionContext(exe_ctx);
139   ExpressionResults result = UserExpression::Evaluate(
140       exe_ctx, options, address_sanitizer_retrieve_report_data_command, "",
141       return_value_sp, eval_error);
142   if (result != eExpressionCompleted) {
143     process_sp->GetTarget().GetDebugger().GetAsyncOutputStream()->Printf(
144         "Warning: Cannot evaluate AddressSanitizer expression:\n%s\n",
145         eval_error.AsCString());
146     return StructuredData::ObjectSP();
147   }
148 
149   int present = return_value_sp->GetValueForExpressionPath(".present")
150                     ->GetValueAsUnsigned(0);
151   if (present != 1)
152     return StructuredData::ObjectSP();
153 
154   addr_t pc =
155       return_value_sp->GetValueForExpressionPath(".pc")->GetValueAsUnsigned(0);
156   /* commented out because rdar://problem/18533301
157   addr_t bp =
158   return_value_sp->GetValueForExpressionPath(".bp")->GetValueAsUnsigned(0);
159   addr_t sp =
160   return_value_sp->GetValueForExpressionPath(".sp")->GetValueAsUnsigned(0);
161   */
162   addr_t address = return_value_sp->GetValueForExpressionPath(".address")
163                        ->GetValueAsUnsigned(0);
164   addr_t access_type =
165       return_value_sp->GetValueForExpressionPath(".access_type")
166           ->GetValueAsUnsigned(0);
167   addr_t access_size =
168       return_value_sp->GetValueForExpressionPath(".access_size")
169           ->GetValueAsUnsigned(0);
170   addr_t description_ptr =
171       return_value_sp->GetValueForExpressionPath(".description")
172           ->GetValueAsUnsigned(0);
173   std::string description;
174   Status error;
175   process_sp->ReadCStringFromMemory(description_ptr, description, error);
176 
177   StructuredData::Dictionary *dict = new StructuredData::Dictionary();
178   dict->AddStringItem("instrumentation_class", "AddressSanitizer");
179   dict->AddStringItem("stop_type", "fatal_error");
180   dict->AddIntegerItem("pc", pc);
181   /* commented out because rdar://problem/18533301
182   dict->AddIntegerItem("bp", bp);
183   dict->AddIntegerItem("sp", sp);
184   */
185   dict->AddIntegerItem("address", address);
186   dict->AddIntegerItem("access_type", access_type);
187   dict->AddIntegerItem("access_size", access_size);
188   dict->AddStringItem("description", description);
189 
190   return StructuredData::ObjectSP(dict);
191 }
192 
193 std::string
FormatDescription(StructuredData::ObjectSP report)194 InstrumentationRuntimeASan::FormatDescription(StructuredData::ObjectSP report) {
195   std::string description = std::string(report->GetAsDictionary()
196                                             ->GetValueForKey("description")
197                                             ->GetAsString()
198                                             ->GetValue());
199   return llvm::StringSwitch<std::string>(description)
200       .Case("heap-use-after-free", "Use of deallocated memory")
201       .Case("heap-buffer-overflow", "Heap buffer overflow")
202       .Case("stack-buffer-underflow", "Stack buffer underflow")
203       .Case("initialization-order-fiasco", "Initialization order problem")
204       .Case("stack-buffer-overflow", "Stack buffer overflow")
205       .Case("stack-use-after-return", "Use of stack memory after return")
206       .Case("use-after-poison", "Use of poisoned memory")
207       .Case("container-overflow", "Container overflow")
208       .Case("stack-use-after-scope", "Use of out-of-scope stack memory")
209       .Case("global-buffer-overflow", "Global buffer overflow")
210       .Case("unknown-crash", "Invalid memory access")
211       .Case("stack-overflow", "Stack space exhausted")
212       .Case("null-deref", "Dereference of null pointer")
213       .Case("wild-jump", "Jump to non-executable address")
214       .Case("wild-addr-write", "Write through wild pointer")
215       .Case("wild-addr-read", "Read from wild pointer")
216       .Case("wild-addr", "Access through wild pointer")
217       .Case("signal", "Deadly signal")
218       .Case("double-free", "Deallocation of freed memory")
219       .Case("new-delete-type-mismatch",
220             "Deallocation size different from allocation size")
221       .Case("bad-free", "Deallocation of non-allocated memory")
222       .Case("alloc-dealloc-mismatch",
223             "Mismatch between allocation and deallocation APIs")
224       .Case("bad-malloc_usable_size", "Invalid argument to malloc_usable_size")
225       .Case("bad-__sanitizer_get_allocated_size",
226             "Invalid argument to __sanitizer_get_allocated_size")
227       .Case("param-overlap",
228             "Call to function disallowing overlapping memory ranges")
229       .Case("negative-size-param", "Negative size used when accessing memory")
230       .Case("bad-__sanitizer_annotate_contiguous_container",
231             "Invalid argument to __sanitizer_annotate_contiguous_container")
232       .Case("odr-violation", "Symbol defined in multiple translation units")
233       .Case(
234           "invalid-pointer-pair",
235           "Comparison or arithmetic on pointers from different memory regions")
236       // for unknown report codes just show the code
237       .Default("AddressSanitizer detected: " + description);
238 }
239 
NotifyBreakpointHit(void * baton,StoppointCallbackContext * context,user_id_t break_id,user_id_t break_loc_id)240 bool InstrumentationRuntimeASan::NotifyBreakpointHit(
241     void *baton, StoppointCallbackContext *context, user_id_t break_id,
242     user_id_t break_loc_id) {
243   assert(baton && "null baton");
244   if (!baton)
245     return false;
246 
247   InstrumentationRuntimeASan *const instance =
248       static_cast<InstrumentationRuntimeASan *>(baton);
249 
250   ProcessSP process_sp = instance->GetProcessSP();
251 
252   if (process_sp->GetModIDRef().IsLastResumeForUserExpression())
253     return false;
254 
255   StructuredData::ObjectSP report = instance->RetrieveReportData();
256   std::string description;
257   if (report) {
258     description = instance->FormatDescription(report);
259   }
260   // Make sure this is the right process
261   if (process_sp && process_sp == context->exe_ctx_ref.GetProcessSP()) {
262     ThreadSP thread_sp = context->exe_ctx_ref.GetThreadSP();
263     if (thread_sp)
264       thread_sp->SetStopInfo(InstrumentationRuntimeStopInfo::
265                                  CreateStopReasonWithInstrumentationData(
266                                      *thread_sp, description, report));
267 
268     StreamFileSP stream_sp(
269         process_sp->GetTarget().GetDebugger().GetOutputStreamSP());
270     if (stream_sp) {
271       stream_sp->Printf("AddressSanitizer report breakpoint hit. Use 'thread "
272                         "info -s' to get extended information about the "
273                         "report.\n");
274     }
275     return true; // Return true to stop the target
276   } else
277     return false; // Let target run
278 }
279 
Activate()280 void InstrumentationRuntimeASan::Activate() {
281   if (IsActive())
282     return;
283 
284   ProcessSP process_sp = GetProcessSP();
285   if (!process_sp)
286     return;
287 
288   ConstString symbol_name("__asan::AsanDie()");
289   const Symbol *symbol = GetRuntimeModuleSP()->FindFirstSymbolWithNameAndType(
290       symbol_name, eSymbolTypeCode);
291 
292   if (symbol == nullptr)
293     return;
294 
295   if (!symbol->ValueIsAddress() || !symbol->GetAddressRef().IsValid())
296     return;
297 
298   Target &target = process_sp->GetTarget();
299   addr_t symbol_address = symbol->GetAddressRef().GetOpcodeLoadAddress(&target);
300 
301   if (symbol_address == LLDB_INVALID_ADDRESS)
302     return;
303 
304   bool internal = true;
305   bool hardware = false;
306   Breakpoint *breakpoint =
307       process_sp->GetTarget()
308           .CreateBreakpoint(symbol_address, internal, hardware)
309           .get();
310   breakpoint->SetCallback(InstrumentationRuntimeASan::NotifyBreakpointHit, this,
311                           true);
312   breakpoint->SetBreakpointKind("address-sanitizer-report");
313   SetBreakpointID(breakpoint->GetID());
314 
315   SetActive(true);
316 }
317 
Deactivate()318 void InstrumentationRuntimeASan::Deactivate() {
319   if (GetBreakpointID() != LLDB_INVALID_BREAK_ID) {
320     ProcessSP process_sp = GetProcessSP();
321     if (process_sp) {
322       process_sp->GetTarget().RemoveBreakpointByID(GetBreakpointID());
323       SetBreakpointID(LLDB_INVALID_BREAK_ID);
324     }
325   }
326   SetActive(false);
327 }
328