blob: 2c31c65514692e483252d41eb5353e557ab16dd5 [file] [log] [blame]
/*
* Copyright (C) 2017 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include "verification.h"
#include <iomanip>
#include <sstream>
#include "art_field-inl.h"
#include "base/file_utils.h"
#include "mirror/class-inl.h"
#include "mirror/object-refvisitor-inl.h"
namespace art {
namespace gc {
std::string Verification::DumpRAMAroundAddress(uintptr_t addr, uintptr_t bytes) const {
const uintptr_t dump_start = addr - bytes;
const uintptr_t dump_end = addr + bytes;
std::ostringstream oss;
if (dump_start < dump_end &&
IsAddressInHeapSpace(reinterpret_cast<const void*>(dump_start)) &&
IsAddressInHeapSpace(reinterpret_cast<const void*>(dump_end - 1))) {
oss << " adjacent_ram=";
for (uintptr_t p = dump_start; p < dump_end; ++p) {
if (p == addr) {
// Marker of where the address is.
oss << "|";
}
uint8_t* ptr = reinterpret_cast<uint8_t*>(p);
oss << std::hex << std::setfill('0') << std::setw(2) << static_cast<uintptr_t>(*ptr);
}
} else {
oss << " <invalid address>";
}
return oss.str();
}
std::string Verification::DumpObjectInfo(const void* addr, const char* tag) const {
std::ostringstream oss;
oss << tag << "=" << addr;
if (IsValidHeapObjectAddress(addr)) {
mirror::Object* obj = reinterpret_cast<mirror::Object*>(const_cast<void*>(addr));
mirror::Class* klass = obj->GetClass<kVerifyNone, kWithoutReadBarrier>();
oss << " klass=" << klass;
if (IsValidClass(klass)) {
oss << "(" << klass->PrettyClass() << ")";
if (klass->IsArrayClass<kVerifyNone>()) {
oss << " length=" << obj->AsArray<kVerifyNone>()->GetLength();
}
} else {
oss << " <invalid address>";
}
space::Space* const space = heap_->FindSpaceFromAddress(addr);
if (space != nullptr) {
oss << " space=" << *space;
}
accounting::CardTable* card_table = heap_->GetCardTable();
if (card_table->AddrIsInCardTable(addr)) {
oss << " card=" << static_cast<size_t>(
card_table->GetCard(reinterpret_cast<const mirror::Object*>(addr)));
}
// Dump adjacent RAM.
oss << DumpRAMAroundAddress(reinterpret_cast<uintptr_t>(addr), 4 * kObjectAlignment);
} else {
oss << " <invalid address>";
}
return oss.str();
}
void Verification::LogHeapCorruption(ObjPtr<mirror::Object> holder,
MemberOffset offset,
mirror::Object* ref,
bool fatal) const {
// Lowest priority logging first:
PrintFileToLog("/proc/self/maps", android::base::LogSeverity::FATAL_WITHOUT_ABORT);
MemMap::DumpMaps(LOG_STREAM(FATAL_WITHOUT_ABORT), /* terse */ true);
// Buffer the output in the string stream since it is more important than the stack traces
// and we want it to have log priority. The stack traces are printed from Runtime::Abort
// which is called from LOG(FATAL) but before the abort message.
std::ostringstream oss;
oss << "GC tried to mark invalid reference " << ref << std::endl;
oss << DumpObjectInfo(ref, "ref") << "\n";
oss << DumpObjectInfo(holder.Ptr(), "holder");
if (holder != nullptr) {
mirror::Class* holder_klass = holder->GetClass<kVerifyNone, kWithoutReadBarrier>();
if (IsValidClass(holder_klass)) {
oss << " field_offset=" << offset.Uint32Value();
ArtField* field = holder->FindFieldByOffset(offset);
if (field != nullptr) {
oss << " name=" << field->GetName();
}
}
mirror::HeapReference<mirror::Object>* addr = holder->GetFieldObjectReferenceAddr(offset);
oss << " reference addr"
<< DumpRAMAroundAddress(reinterpret_cast<uintptr_t>(addr), 4 * kObjectAlignment);
}
if (fatal) {
LOG(FATAL) << oss.str();
} else {
LOG(FATAL_WITHOUT_ABORT) << oss.str();
}
}
bool Verification::IsAddressInHeapSpace(const void* addr, space::Space** out_space) const {
space::Space* const space = heap_->FindSpaceFromAddress(addr);
if (space != nullptr) {
if (out_space != nullptr) {
*out_space = space;
}
return true;
}
return false;
}
bool Verification::IsValidHeapObjectAddress(const void* addr, space::Space** out_space) const {
return IsAligned<kObjectAlignment>(addr) && IsAddressInHeapSpace(addr, out_space);
}
bool Verification::IsValidClass(const void* addr) const {
if (!IsValidHeapObjectAddress(addr)) {
return false;
}
mirror::Class* klass = reinterpret_cast<mirror::Class*>(const_cast<void*>(addr));
mirror::Class* k1 = klass->GetClass<kVerifyNone, kWithoutReadBarrier>();
if (!IsValidHeapObjectAddress(k1)) {
return false;
}
// `k1` should be class class, take the class again to verify.
// Note that this check may not be valid for the no image space since the class class might move
// around from moving GC.
mirror::Class* k2 = k1->GetClass<kVerifyNone, kWithoutReadBarrier>();
if (!IsValidHeapObjectAddress(k2)) {
return false;
}
return k1 == k2;
}
using ObjectSet = std::set<mirror::Object*>;
using WorkQueue = std::deque<std::pair<mirror::Object*, std::string>>;
// Use for visiting the GcRoots held live by ArtFields, ArtMethods, and ClassLoaders.
class Verification::BFSFindReachable {
public:
explicit BFSFindReachable(ObjectSet* visited) : visited_(visited) {}
void operator()(mirror::Object* obj, MemberOffset offset, bool is_static ATTRIBUTE_UNUSED) const
REQUIRES_SHARED(Locks::mutator_lock_) {
ArtField* field = obj->FindFieldByOffset(offset);
Visit(obj->GetFieldObject<mirror::Object>(offset),
field != nullptr ? field->GetName() : "");
}
void VisitRootIfNonNull(mirror::CompressedReference<mirror::Object>* root) const
REQUIRES_SHARED(Locks::mutator_lock_) {
if (!root->IsNull()) {
VisitRoot(root);
}
}
void VisitRoot(mirror::CompressedReference<mirror::Object>* root) const
REQUIRES_SHARED(Locks::mutator_lock_) {
Visit(root->AsMirrorPtr(), "!nativeRoot");
}
void Visit(mirror::Object* ref, const std::string& field_name) const
REQUIRES_SHARED(Locks::mutator_lock_) {
if (ref != nullptr && visited_->insert(ref).second) {
new_visited_.emplace_back(ref, field_name);
}
}
const WorkQueue& NewlyVisited() const {
return new_visited_;
}
private:
ObjectSet* visited_;
mutable WorkQueue new_visited_;
};
class Verification::CollectRootVisitor : public SingleRootVisitor {
public:
CollectRootVisitor(ObjectSet* visited, WorkQueue* work) : visited_(visited), work_(work) {}
void VisitRoot(mirror::Object* obj, const RootInfo& info)
override REQUIRES_SHARED(Locks::mutator_lock_) {
if (obj != nullptr && visited_->insert(obj).second) {
std::ostringstream oss;
oss << info.ToString() << " = " << obj << "(" << obj->PrettyTypeOf() << ")";
work_->emplace_back(obj, oss.str());
}
}
private:
ObjectSet* const visited_;
WorkQueue* const work_;
};
std::string Verification::FirstPathFromRootSet(ObjPtr<mirror::Object> target) const {
Runtime* const runtime = Runtime::Current();
std::set<mirror::Object*> visited;
std::deque<std::pair<mirror::Object*, std::string>> work;
{
CollectRootVisitor root_visitor(&visited, &work);
runtime->VisitRoots(&root_visitor, kVisitRootFlagAllRoots);
}
while (!work.empty()) {
auto pair = work.front();
work.pop_front();
if (pair.first == target) {
return pair.second;
}
BFSFindReachable visitor(&visited);
pair.first->VisitReferences(visitor, VoidFunctor());
for (auto&& pair2 : visitor.NewlyVisited()) {
std::ostringstream oss;
mirror::Object* obj = pair2.first;
oss << pair.second << " -> " << obj << "(" << obj->PrettyTypeOf() << ")." << pair2.second;
work.emplace_back(obj, oss.str());
}
}
return "<no path found>";
}
} // namespace gc
} // namespace art