1 /*
2 * Copyright (C) 2017 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 #include "verification-inl.h"
18
19 #include <iomanip>
20 #include <sstream>
21
22 #include "art_field-inl.h"
23 #include "base/file_utils.h"
24 #include "base/logging.h"
25 #include "mirror/class-inl.h"
26 #include "mirror/object-refvisitor-inl.h"
27
28 namespace art {
29 namespace gc {
30
DumpRAMAroundAddress(uintptr_t addr,uintptr_t bytes) const31 std::string Verification::DumpRAMAroundAddress(uintptr_t addr, uintptr_t bytes) const {
32 uintptr_t* dump_start = reinterpret_cast<uintptr_t*>(addr - bytes);
33 uintptr_t* dump_end = reinterpret_cast<uintptr_t*>(addr + bytes);
34 std::ostringstream oss;
35 oss << " adjacent_ram=";
36 for (const uintptr_t* p = dump_start; p < dump_end; ++p) {
37 if (p == reinterpret_cast<uintptr_t*>(addr)) {
38 // Marker of where the address is.
39 oss << "|";
40 }
41 oss << std::hex << std::setfill('0') << std::setw(sizeof(uintptr_t) * 2) << *p << " ";
42 }
43 return oss.str();
44 }
45
DumpObjectInfo(const void * addr,const char * tag) const46 std::string Verification::DumpObjectInfo(const void* addr, const char* tag) const {
47 std::ostringstream oss;
48 oss << tag << "=" << addr;
49 if (IsValidHeapObjectAddress(addr)) {
50 mirror::Object* obj = reinterpret_cast<mirror::Object*>(const_cast<void*>(addr));
51 mirror::Class* klass = obj->GetClass<kVerifyNone, kWithoutReadBarrier>();
52 oss << " klass=" << klass;
53 if (IsValidClass(klass)) {
54 oss << "(" << klass->PrettyClass() << ")";
55 if (klass->IsArrayClass<kVerifyNone>()) {
56 oss << " length=" << obj->AsArray<kVerifyNone>()->GetLength();
57 }
58 } else {
59 oss << " <invalid address>";
60 }
61 space::Space* const space = heap_->FindSpaceFromAddress(addr);
62 if (space != nullptr) {
63 oss << " space=" << *space;
64 }
65 accounting::CardTable* card_table = heap_->GetCardTable();
66 if (card_table->AddrIsInCardTable(addr)) {
67 oss << " card=" << static_cast<size_t>(
68 card_table->GetCard(reinterpret_cast<const mirror::Object*>(addr)));
69 }
70 // Dump adjacent RAM.
71 oss << DumpRAMAroundAddress(reinterpret_cast<uintptr_t>(addr), 4 * kObjectAlignment);
72 } else {
73 oss << " <invalid address>";
74 }
75 return oss.str();
76 }
77
LogHeapCorruption(ObjPtr<mirror::Object> holder,MemberOffset offset,mirror::Object * ref,bool fatal) const78 void Verification::LogHeapCorruption(ObjPtr<mirror::Object> holder,
79 MemberOffset offset,
80 mirror::Object* ref,
81 bool fatal) const {
82 // Highest priority logging first.
83 // Buffer the output in the string stream since it is more important than the stack traces
84 // and we want it to have log priority. The stack traces are printed from Runtime::Abort
85 // which is called from LOG(FATAL) but before the abort message.
86 std::ostringstream oss;
87 oss << "GC tried to mark invalid reference " << ref << std::endl;
88 oss << DumpObjectInfo(ref, "ref") << "\n";
89 oss << DumpObjectInfo(holder.Ptr(), "holder") << "\n";
90 if (holder != nullptr) {
91 mirror::Class* holder_klass = holder->GetClass<kVerifyNone, kWithoutReadBarrier>();
92 if (IsValidClass(holder_klass)) {
93 oss << " field_offset=" << offset.Uint32Value();
94 ArtField* field = holder->FindFieldByOffset(offset);
95 if (field != nullptr) {
96 oss << " name=" << field->GetName();
97 }
98 }
99 mirror::HeapReference<mirror::Object>* addr = holder->GetFieldObjectReferenceAddr(offset);
100 oss << " reference addr"
101 << DumpRAMAroundAddress(reinterpret_cast<uintptr_t>(addr), 4 * kObjectAlignment);
102 }
103 Runtime::Current()->GetHeap()->DumpSpaces(oss);
104 MemMap::DumpMaps(oss, /* terse= */ true);
105
106 if (fatal) {
107 LOG(FATAL) << oss.str();
108 } else {
109 LOG(FATAL_WITHOUT_ABORT) << oss.str();
110 }
111 }
112
IsAddressInHeapSpace(const void * addr,space::Space ** out_space) const113 bool Verification::IsAddressInHeapSpace(const void* addr, space::Space** out_space) const {
114 space::Space* const space = heap_->FindSpaceFromAddress(addr);
115 if (space != nullptr) {
116 if (out_space != nullptr) {
117 *out_space = space;
118 }
119 return true;
120 }
121 return false;
122 }
123
IsValidHeapObjectAddress(const void * addr,space::Space ** out_space) const124 bool Verification::IsValidHeapObjectAddress(const void* addr, space::Space** out_space) const {
125 return IsAligned<kObjectAlignment>(addr) && IsAddressInHeapSpace(addr, out_space);
126 }
127
128 using ObjectSet = std::set<mirror::Object*>;
129 using WorkQueue = std::deque<std::pair<mirror::Object*, std::string>>;
130
131 // Use for visiting the GcRoots held live by ArtFields, ArtMethods, and ClassLoaders.
132 class Verification::BFSFindReachable {
133 public:
BFSFindReachable(ObjectSet * visited)134 explicit BFSFindReachable(ObjectSet* visited) : visited_(visited) {}
135
operator ()(mirror::Object * obj,MemberOffset offset,bool is_static ATTRIBUTE_UNUSED) const136 void operator()(mirror::Object* obj, MemberOffset offset, bool is_static ATTRIBUTE_UNUSED) const
137 REQUIRES_SHARED(Locks::mutator_lock_) {
138 ArtField* field = obj->FindFieldByOffset(offset);
139 Visit(obj->GetFieldObject<mirror::Object>(offset),
140 field != nullptr ? field->GetName() : "");
141 }
142
VisitRootIfNonNull(mirror::CompressedReference<mirror::Object> * root) const143 void VisitRootIfNonNull(mirror::CompressedReference<mirror::Object>* root) const
144 REQUIRES_SHARED(Locks::mutator_lock_) {
145 if (!root->IsNull()) {
146 VisitRoot(root);
147 }
148 }
149
VisitRoot(mirror::CompressedReference<mirror::Object> * root) const150 void VisitRoot(mirror::CompressedReference<mirror::Object>* root) const
151 REQUIRES_SHARED(Locks::mutator_lock_) {
152 Visit(root->AsMirrorPtr(), "!nativeRoot");
153 }
154
Visit(mirror::Object * ref,const std::string & field_name) const155 void Visit(mirror::Object* ref, const std::string& field_name) const
156 REQUIRES_SHARED(Locks::mutator_lock_) {
157 if (ref != nullptr && visited_->insert(ref).second) {
158 new_visited_.emplace_back(ref, field_name);
159 }
160 }
161
NewlyVisited() const162 const WorkQueue& NewlyVisited() const {
163 return new_visited_;
164 }
165
166 private:
167 ObjectSet* visited_;
168 mutable WorkQueue new_visited_;
169 };
170
171 class Verification::CollectRootVisitor : public SingleRootVisitor {
172 public:
CollectRootVisitor(ObjectSet * visited,WorkQueue * work)173 CollectRootVisitor(ObjectSet* visited, WorkQueue* work) : visited_(visited), work_(work) {}
174
VisitRoot(mirror::Object * obj,const RootInfo & info)175 void VisitRoot(mirror::Object* obj, const RootInfo& info)
176 override REQUIRES_SHARED(Locks::mutator_lock_) {
177 if (obj != nullptr && visited_->insert(obj).second) {
178 std::ostringstream oss;
179 oss << info.ToString() << " = " << obj << "(" << obj->PrettyTypeOf() << ")";
180 work_->emplace_back(obj, oss.str());
181 }
182 }
183
184 private:
185 ObjectSet* const visited_;
186 WorkQueue* const work_;
187 };
188
FirstPathFromRootSet(ObjPtr<mirror::Object> target) const189 std::string Verification::FirstPathFromRootSet(ObjPtr<mirror::Object> target) const {
190 Runtime* const runtime = Runtime::Current();
191 std::set<mirror::Object*> visited;
192 std::deque<std::pair<mirror::Object*, std::string>> work;
193 {
194 CollectRootVisitor root_visitor(&visited, &work);
195 runtime->VisitRoots(&root_visitor, kVisitRootFlagAllRoots);
196 }
197 while (!work.empty()) {
198 auto pair = work.front();
199 work.pop_front();
200 if (pair.first == target) {
201 return pair.second;
202 }
203 BFSFindReachable visitor(&visited);
204 pair.first->VisitReferences(visitor, VoidFunctor());
205 for (auto&& pair2 : visitor.NewlyVisited()) {
206 std::ostringstream oss;
207 mirror::Object* obj = pair2.first;
208 oss << pair.second << " -> " << obj << "(" << obj->PrettyTypeOf() << ")." << pair2.second;
209 work.emplace_back(obj, oss.str());
210 }
211 }
212 return "<no path found>";
213 }
214
215 } // namespace gc
216 } // namespace art
217