/*
* Copyright (c) 1998, 2019, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*
*/
#include "precompiled.hpp"
#include "jvm.h"
#include "classfile/classFileStream.hpp"
#include "classfile/classLoader.hpp"
#include "classfile/javaClasses.hpp"
#include "classfile/stackMapTable.hpp"
#include "classfile/stackMapFrame.hpp"
#include "classfile/stackMapTableFormat.hpp"
#include "classfile/symbolTable.hpp"
#include "classfile/systemDictionary.hpp"
#include "classfile/verifier.hpp"
#include "classfile/vmSymbols.hpp"
#include "interpreter/bytecodes.hpp"
#include "interpreter/bytecodeStream.hpp"
#include "logging/log.hpp"
#include "logging/logStream.hpp"
#include "memory/oopFactory.hpp"
#include "memory/resourceArea.hpp"
#include "memory/universe.hpp"
#include "oops/constantPool.inline.hpp"
#include "oops/instanceKlass.hpp"
#include "oops/oop.inline.hpp"
#include "oops/typeArrayOop.hpp"
#include "runtime/fieldDescriptor.hpp"
#include "runtime/handles.inline.hpp"
#include "runtime/interfaceSupport.inline.hpp"
#include "runtime/javaCalls.hpp"
#include "runtime/jniHandles.inline.hpp"
#include "runtime/os.hpp"
#include "runtime/safepointVerifiers.hpp"
#include "runtime/thread.hpp"
#include "services/threadService.hpp"
#include "utilities/align.hpp"
#include "utilities/bytes.hpp"
#define NOFAILOVER_MAJOR_VERSION 51
#define NONZERO_PADDING_BYTES_IN_SWITCH_MAJOR_VERSION 51
#define STATIC_METHOD_IN_INTERFACE_MAJOR_VERSION 52
#define MAX_ARRAY_DIMENSIONS 255
// Access to external entry for VerifyClassForMajorVersion - old byte code verifier
extern "C" {
typedef jboolean (*verify_byte_codes_fn_t)(JNIEnv *, jclass, char *, jint, jint);
}
static verify_byte_codes_fn_t volatile _verify_byte_codes_fn = NULL;
static verify_byte_codes_fn_t verify_byte_codes_fn() {
if (_verify_byte_codes_fn != NULL)
return _verify_byte_codes_fn;
MutexLocker locker(Verify_lock);
if (_verify_byte_codes_fn != NULL)
return _verify_byte_codes_fn;
// Load verify dll
char buffer[JVM_MAXPATHLEN];
char ebuf[1024];
if (!os::dll_locate_lib(buffer, sizeof(buffer), Arguments::get_dll_dir(), "verify"))
return NULL; // Caller will throw VerifyError
void *lib_handle = os::dll_load(buffer, ebuf, sizeof(ebuf));
if (lib_handle == NULL)
return NULL; // Caller will throw VerifyError
void *fn = os::dll_lookup(lib_handle, "VerifyClassForMajorVersion");
if (fn == NULL)
return NULL; // Caller will throw VerifyError
return _verify_byte_codes_fn = CAST_TO_FN_PTR(verify_byte_codes_fn_t, fn);
}
// Methods in Verifier
bool Verifier::should_verify_for(oop class_loader, bool should_verify_class) {
return (class_loader == NULL || !should_verify_class) ?
BytecodeVerificationLocal : BytecodeVerificationRemote;
}
bool Verifier::relax_access_for(oop loader) {
bool trusted = java_lang_ClassLoader::is_trusted_loader(loader);
bool need_verify =
// verifyAll
(BytecodeVerificationLocal && BytecodeVerificationRemote) ||
// verifyRemote
(!BytecodeVerificationLocal && BytecodeVerificationRemote && !trusted);
return !need_verify;
}
void Verifier::trace_class_resolution(Klass* resolve_class, InstanceKlass* verify_class) {
assert(verify_class != NULL, "Unexpected null verify_class");
ResourceMark rm;
Symbol* s = verify_class->source_file_name();
const char* source_file = (s != NULL ? s->as_C_string() : NULL);
const char* verify = verify_class->external_name();
const char* resolve = resolve_class->external_name();
// print in a single call to reduce interleaving between threads
if (source_file != NULL) {
log_debug(class, resolve)("%s %s %s (verification)", verify, resolve, source_file);
} else {
log_debug(class, resolve)("%s %s (verification)", verify, resolve);
}
}
// Prints the end-verification message to the appropriate output.
void Verifier::log_end_verification(outputStream* st, const char* klassName, Symbol* exception_name, TRAPS) {
if (HAS_PENDING_EXCEPTION) {
st->print("Verification for %s has", klassName);
st->print_cr(" exception pending %s ",
PENDING_EXCEPTION->klass()->external_name());
} else if (exception_name != NULL) {
st->print_cr("Verification for %s failed", klassName);
}
st->print_cr("End class verification for: %s", klassName);
}
bool Verifier::verify(InstanceKlass* klass, bool should_verify_class, TRAPS) {
HandleMark hm(THREAD);
ResourceMark rm(THREAD);
// Eagerly allocate the identity hash code for a klass. This is a fallout
// from 6320749 and 8059924: hash code generator is not supposed to be called
// during the safepoint, but it allows to sneak the hashcode in during
// verification. Without this eager hashcode generation, we may end up
// installing the hashcode during some other operation, which may be at
// safepoint -- blowing up the checks. It was previously done as the side
// effect (sic!) for external_name(), but instead of doing that, we opt to
// explicitly push the hashcode in here. This is signify the following block
// is IMPORTANT:
if (klass->java_mirror() != NULL) {
klass->java_mirror()->identity_hash();
}
if (!is_eligible_for_verification(klass, should_verify_class)) {
return true;
}
// Timer includes any side effects of class verification (resolution,
// etc), but not recursive calls to Verifier::verify().
JavaThread* jt = (JavaThread*)THREAD;
PerfClassTraceTime timer(ClassLoader::perf_class_verify_time(),
ClassLoader::perf_class_verify_selftime(),
ClassLoader::perf_classes_verified(),
jt->get_thread_stat()->perf_recursion_counts_addr(),
jt->get_thread_stat()->perf_timers_addr(),
PerfClassTraceTime::CLASS_VERIFY);
// If the class should be verified, first see if we can use the split
// verifier. If not, or if verification fails and can failover, then
// call the inference verifier.
Symbol* exception_name = NULL;
const size_t message_buffer_len = klass->name()->utf8_length() + 1024;
char* message_buffer = NULL;
char* exception_message = NULL;
log_info(class, init)("Start class verification for: %s", klass->external_name());
if (klass->major_version() >= STACKMAP_ATTRIBUTE_MAJOR_VERSION) {
ClassVerifier split_verifier(klass, THREAD);
split_verifier.verify_class(THREAD);
exception_name = split_verifier.result();
// If DumpSharedSpaces is set then don't fall back to the old verifier on
// verification failure. If a class fails verification with the split verifier,
// it might fail the CDS runtime verifier constraint check. In that case, we
// don't want to share the class. We only archive classes that pass the split
// verifier.
bool can_failover = !DumpSharedSpaces &&
klass->major_version() < NOFAILOVER_MAJOR_VERSION;
if (can_failover && !HAS_PENDING_EXCEPTION && // Split verifier doesn't set PENDING_EXCEPTION for failure
(exception_name == vmSymbols::java_lang_VerifyError() ||
exception_name == vmSymbols::java_lang_ClassFormatError())) {
log_info(verification)("Fail over class verification to old verifier for: %s", klass->external_name());
log_info(class, init)("Fail over class verification to old verifier for: %s", klass->external_name());
message_buffer = NEW_RESOURCE_ARRAY(char, message_buffer_len);
exception_message = message_buffer;
exception_name = inference_verify(
klass, message_buffer, message_buffer_len, THREAD);
}
if (exception_name != NULL) {
exception_message = split_verifier.exception_message();
}
} else {
message_buffer = NEW_RESOURCE_ARRAY(char, message_buffer_len);
exception_message = message_buffer;
exception_name = inference_verify(
klass, message_buffer, message_buffer_len, THREAD);
}
LogTarget(Info, class, init) lt1;
if (lt1.is_enabled()) {
LogStream ls(lt1);
log_end_verification(&ls, klass->external_name(), exception_name, THREAD);
}
LogTarget(Info, verification) lt2;
if (lt2.is_enabled()) {
LogStream ls(lt2);
log_end_verification(&ls, klass->external_name(), exception_name, THREAD);
}
if (HAS_PENDING_EXCEPTION) {
return false; // use the existing exception
} else if (exception_name == NULL) {
return true; // verification succeeded
} else { // VerifyError or ClassFormatError to be created and thrown
Klass* kls =
SystemDictionary::resolve_or_fail(exception_name, true, CHECK_false);
if (log_is_enabled(Debug, class, resolve)) {
Verifier::trace_class_resolution(kls, klass);
}
while (kls != NULL) {
if (kls == klass) {
// If the class being verified is the exception we're creating
// or one of it's superclasses, we're in trouble and are going
// to infinitely recurse when we try to initialize the exception.
// So bail out here by throwing the preallocated VM error.
THROW_OOP_(Universe::virtual_machine_error_instance(), false);
}
kls = kls->super();
}
if (message_buffer != NULL) {
message_buffer[message_buffer_len - 1] = '\0'; // just to be sure
}
assert(exception_message != NULL, "");
THROW_MSG_(exception_name, exception_message, false);
}
}
bool Verifier::is_eligible_for_verification(InstanceKlass* klass, bool should_verify_class) {
Symbol* name = klass->name();
Klass* refl_magic_klass = SystemDictionary::reflect_MagicAccessorImpl_klass();
bool is_reflect = refl_magic_klass != NULL && klass->is_subtype_of(refl_magic_klass);
return (should_verify_for(klass->class_loader(), should_verify_class) &&
// return if the class is a bootstrapping class
// or defineClass specified not to verify by default (flags override passed arg)
// We need to skip the following four for bootstraping
name != vmSymbols::java_lang_Object() &&
name != vmSymbols::java_lang_Class() &&
name != vmSymbols::java_lang_String() &&
name != vmSymbols::java_lang_Throwable() &&
// Can not verify the bytecodes for shared classes because they have
// already been rewritten to contain constant pool cache indices,
// which the verifier can't understand.
// Shared classes shouldn't have stackmaps either.
!klass->is_shared() &&
// As of the fix for 4486457 we disable verification for all of the
// dynamically-generated bytecodes associated with the 1.4
// reflection implementation, not just those associated with
// jdk/internal/reflect/SerializationConstructorAccessor.
// NOTE: this is called too early in the bootstrapping process to be
// guarded by Universe::is_gte_jdk14x_version().
// Also for lambda generated code, gte jdk8
(!is_reflect));
}
Symbol* Verifier::inference_verify(
InstanceKlass* klass, char* message, size_t message_len, TRAPS) {
JavaThread* thread = (JavaThread*)THREAD;
JNIEnv *env = thread->jni_environment();
verify_byte_codes_fn_t verify_func = verify_byte_codes_fn();
if (verify_func == NULL) {
jio_snprintf(message, message_len, "Could not link verifier");
return vmSymbols::java_lang_VerifyError();
}
ResourceMark rm(THREAD);
log_info(verification)("Verifying class %s with old format", klass->external_name());
jclass cls = (jclass) JNIHandles::make_local(env, klass->java_mirror());
jint result;
{
HandleMark hm(thread);
ThreadToNativeFromVM ttn(thread);
// ThreadToNativeFromVM takes care of changing thread_state, so safepoint
// code knows that we have left the VM
result = (*verify_func)(env, cls, message, (int)message_len, klass->major_version());
}
JNIHandles::destroy_local(cls);
// These numbers are chosen so that VerifyClassCodes interface doesn't need
// to be changed (still return jboolean (unsigned char)), and result is
// 1 when verification is passed.
if (result == 0) {
return vmSymbols::java_lang_VerifyError();
} else if (result == 1) {
return NULL; // verified.
} else if (result == 2) {
THROW_MSG_(vmSymbols::java_lang_OutOfMemoryError(), message, NULL);
} else if (result == 3) {
return vmSymbols::java_lang_ClassFormatError();
} else {
ShouldNotReachHere();
return NULL;
}
}
TypeOrigin TypeOrigin::null() {
return TypeOrigin();
}
TypeOrigin TypeOrigin::local(u2 index, StackMapFrame* frame) {
assert(frame != NULL, "Must have a frame");
return TypeOrigin(CF_LOCALS, index, StackMapFrame::copy(frame),
frame->local_at(index));
}
TypeOrigin TypeOrigin::stack(u2 index, StackMapFrame* frame) {
assert(frame != NULL, "Must have a frame");
return TypeOrigin(CF_STACK, index, StackMapFrame::copy(frame),
frame->stack_at(index));
}
TypeOrigin TypeOrigin::sm_local(u2 index, StackMapFrame* frame) {
assert(frame != NULL, "Must have a frame");
return TypeOrigin(SM_LOCALS, index, StackMapFrame::copy(frame),
frame->local_at(index));
}
TypeOrigin TypeOrigin::sm_stack(u2 index, StackMapFrame* frame) {
assert(frame != NULL, "Must have a frame");
return TypeOrigin(SM_STACK, index, StackMapFrame::copy(frame),
frame->stack_at(index));
}
TypeOrigin TypeOrigin::bad_index(u2 index) {
return TypeOrigin(BAD_INDEX, index, NULL, VerificationType::bogus_type());
}
TypeOrigin TypeOrigin::cp(u2 index, VerificationType vt) {
return TypeOrigin(CONST_POOL, index, NULL, vt);
}
TypeOrigin TypeOrigin::signature(VerificationType vt) {
return TypeOrigin(SIG, 0, NULL, vt);
}
TypeOrigin TypeOrigin::implicit(VerificationType t) {
return TypeOrigin(IMPLICIT, 0, NULL, t);
}
TypeOrigin TypeOrigin::frame(StackMapFrame* frame) {
return TypeOrigin(FRAME_ONLY, 0, StackMapFrame::copy(frame),
VerificationType::bogus_type());
}
void TypeOrigin::reset_frame() {
if (_frame != NULL) {
_frame->restore();
}
}
void TypeOrigin::details(outputStream* ss) const {
_type.print_on(ss);
switch (_origin) {
case CF_LOCALS:
ss->print(" (current frame, locals[%d])", _index);
break;
case CF_STACK:
ss->print(" (current frame, stack[%d])", _index);
break;
case SM_LOCALS:
ss->print(" (stack map, locals[%d])", _index);
break;
case SM_STACK:
ss->print(" (stack map, stack[%d])", _index);
break;
case CONST_POOL:
ss->print(" (constant pool %d)", _index);
break;
case SIG:
ss->print(" (from method signature)");
break;
case IMPLICIT:
case FRAME_ONLY:
case NONE:
default:
;
}
}
#ifdef ASSERT
void TypeOrigin::print_on(outputStream* str) const {
str->print("{%d,%d,%p:", _origin, _index, _frame);
if (_frame != NULL) {
_frame->print_on(str);
} else {
str->print("null");
}
str->print(",");
_type.print_on(str);
str->print("}");
}
#endif
void ErrorContext::details(outputStream* ss, const Method* method) const {
if (is_valid()) {
ss->cr();
ss->print_cr("Exception Details:");
location_details(ss, method);
reason_details(ss);
frame_details(ss);
bytecode_details(ss, method);
handler_details(ss, method);
stackmap_details(ss, method);
}
}
void ErrorContext::reason_details(outputStream* ss) const {
streamIndentor si(ss);
ss->indent().print_cr("Reason:");
streamIndentor si2(ss);
ss->indent().print("%s", "");
switch (_fault) {
case INVALID_BYTECODE:
ss->print("Error exists in the bytecode");
break;
case WRONG_TYPE:
if (_expected.is_valid()) {
ss->print("Type ");
_type.details(ss);
ss->print(" is not assignable to ");
_expected.details(ss);
} else {
ss->print("Invalid type: ");
_type.details(ss);
}
break;
case FLAGS_MISMATCH:
if (_expected.is_valid()) {
ss->print("Current frame's flags are not assignable "
"to stack map frame's.");
} else {
ss->print("Current frame's flags are invalid in this context.");
}
break;
case BAD_CP_INDEX:
ss->print("Constant pool index %d is invalid", _type.index());
break;
case BAD_LOCAL_INDEX:
ss->print("Local index %d is invalid", _type.index());
break;
case LOCALS_SIZE_MISMATCH:
ss->print("Current frame's local size doesn't match stackmap.");
break;
case STACK_SIZE_MISMATCH:
ss->print("Current frame's stack size doesn't match stackmap.");
break;
case STACK_OVERFLOW:
ss->print("Exceeded max stack size.");
break;
case STACK_UNDERFLOW:
ss->print("Attempt to pop empty stack.");
break;
case MISSING_STACKMAP:
ss->print("Expected stackmap frame at this location.");
break;
case BAD_STACKMAP:
ss->print("Invalid stackmap specification.");
break;
case UNKNOWN:
default:
ShouldNotReachHere();
ss->print_cr("Unknown");
}
ss->cr();
}
void ErrorContext::location_details(outputStream* ss, const Method* method) const {
if (_bci != -1 && method != NULL) {
streamIndentor si(ss);
const char* bytecode_name = "<invalid>";
if (method->validate_bci(_bci) != -1) {
Bytecodes::Code code = Bytecodes::code_or_bp_at(method->bcp_from(_bci));
if (Bytecodes::is_defined(code)) {
bytecode_name = Bytecodes::name(code);
} else {
bytecode_name = "<illegal>";
}
}
InstanceKlass* ik = method->method_holder();
ss->indent().print_cr("Location:");
streamIndentor si2(ss);
ss->indent().print_cr("%s.%s%s @%d: %s",
ik->name()->as_C_string(), method->name()->as_C_string(),
method->signature()->as_C_string(), _bci, bytecode_name);
}
}
void ErrorContext::frame_details(outputStream* ss) const {
streamIndentor si(ss);
if (_type.is_valid() && _type.frame() != NULL) {
ss->indent().print_cr("Current Frame:");
streamIndentor si2(ss);
_type.frame()->print_on(ss);
}
if (_expected.is_valid() && _expected.frame() != NULL) {
ss->indent().print_cr("Stackmap Frame:");
streamIndentor si2(ss);
_expected.frame()->print_on(ss);
}
}
void ErrorContext::bytecode_details(outputStream* ss, const Method* method) const {
if (method != NULL) {
streamIndentor si(ss);
ss->indent().print_cr("Bytecode:");
streamIndentor si2(ss);
ss->print_data(method->code_base(), method->code_size(), false);
}
}
void ErrorContext::handler_details(outputStream* ss, const Method* method) const {
if (method != NULL) {
streamIndentor si(ss);
ExceptionTable table(method);
if (table.length() > 0) {
ss->indent().print_cr("Exception Handler Table:");
streamIndentor si2(ss);
for (int i = 0; i < table.length(); ++i) {
ss->indent().print_cr("bci [%d, %d] => handler: %d", table.start_pc(i),
table.end_pc(i), table.handler_pc(i));
}
}
}
}
void ErrorContext::stackmap_details(outputStream* ss, const Method* method) const {
if (method != NULL && method->has_stackmap_table()) {
streamIndentor si(ss);
ss->indent().print_cr("Stackmap Table:");
Array<u1>* data = method->stackmap_data();
stack_map_table* sm_table =
stack_map_table::at((address)data->adr_at(0));
stack_map_frame* sm_frame = sm_table->entries();
streamIndentor si2(ss);
int current_offset = -1;
address end_of_sm_table = (address)sm_table + method->stackmap_data()->length();
for (u2 i = 0; i < sm_table->number_of_entries(); ++i) {
ss->indent();
if (!sm_frame->verify((address)sm_frame, end_of_sm_table)) {
sm_frame->print_truncated(ss, current_offset);
return;
}
sm_frame->print_on(ss, current_offset);
ss->cr();
current_offset += sm_frame->offset_delta();
sm_frame = sm_frame->next();
}
}
}
// Methods in ClassVerifier
ClassVerifier::ClassVerifier(
InstanceKlass* klass, TRAPS)
: _thread(THREAD), _previous_symbol(NULL), _symbols(NULL), _exception_type(NULL),
_message(NULL), _method_signatures_table(NULL), _klass(klass) {
_this_type = VerificationType::reference_type(klass->name());
}
ClassVerifier::~ClassVerifier() {
// Decrement the reference count for any symbols created.
if (_symbols != NULL) {
for (int i = 0; i < _symbols->length(); i++) {
Symbol* s = _symbols->at(i);
s->decrement_refcount();
}
}
}
VerificationType ClassVerifier::object_type() const {
return VerificationType::reference_type(vmSymbols::java_lang_Object());
}
TypeOrigin ClassVerifier::ref_ctx(const char* sig) {
VerificationType vt = VerificationType::reference_type(
create_temporary_symbol(sig, (int)strlen(sig)));
return TypeOrigin::implicit(vt);
}
void ClassVerifier::verify_class(TRAPS) {
log_info(verification)("Verifying class %s with new format", _klass->external_name());
// Either verifying both local and remote classes or just remote classes.
assert(BytecodeVerificationRemote, "Should not be here");
// Create hash table containing method signatures.
method_signatures_table_type method_signatures_table;
set_method_signatures_table(&method_signatures_table);
Array<Method*>* methods = _klass->methods();
int num_methods = methods->length();
for (int index = 0; index < num_methods; index++) {
// Check for recursive re-verification before each method.
if (was_recursively_verified()) return;
Method* m = methods->at(index);
if (m->is_native() || m->is_abstract() || m->is_overpass()) {
// If m is native or abstract, skip it. It is checked in class file
// parser that methods do not override a final method. Overpass methods
// are trusted since the VM generates them.
continue;
}
verify_method(methodHandle(THREAD, m), CHECK_VERIFY(this));
}
if (was_recursively_verified()){
log_info(verification)("Recursive verification detected for: %s", _klass->external_name());
log_info(class, init)("Recursive verification detected for: %s",
_klass->external_name());
}
}
// Translate the signature entries into verification types and save them in
// the growable array. Also, save the count of arguments.
void ClassVerifier::translate_signature(Symbol* const method_sig,
sig_as_verification_types* sig_verif_types,
TRAPS) {
SignatureStream sig_stream(method_sig);
VerificationType sig_type[2];
int sig_i = 0;
GrowableArray<VerificationType>* verif_types = sig_verif_types->sig_verif_types();
// Translate the signature arguments into verification types.
while (!sig_stream.at_return_type()) {
int n = change_sig_to_verificationType(&sig_stream, sig_type);
assert(n <= 2, "Unexpected signature type");
// Store verification type(s). Longs and Doubles each have two verificationTypes.
for (int x = 0; x < n; x++) {
verif_types->push(sig_type[x]);
}
sig_i += n;
sig_stream.next();
}
// Set final arg count, not including the return type. The final arg count will
// be compared with sig_verify_types' length to see if there is a return type.
sig_verif_types->set_num_args(sig_i);
// Store verification type(s) for the return type, if there is one.
if (sig_stream.type() != T_VOID) {
int n = change_sig_to_verificationType(&sig_stream, sig_type);
assert(n <= 2, "Unexpected signature return type");
for (int y = 0; y < n; y++) {
verif_types->push(sig_type[y]);
}
}
}
void ClassVerifier::create_method_sig_entry(sig_as_verification_types* sig_verif_types,
int sig_index, TRAPS) {
// Translate the signature into verification types.
ConstantPool* cp = _klass->constants();
Symbol* const method_sig = cp->symbol_at(sig_index);
translate_signature(method_sig, sig_verif_types, CHECK_VERIFY(this));
// Add the list of this signature's verification types to the table.
bool is_unique = method_signatures_table()->put(sig_index, sig_verif_types);
assert(is_unique, "Duplicate entries in method_signature_table");
}
void ClassVerifier::verify_method(const methodHandle& m, TRAPS) {
HandleMark hm(THREAD);
_method = m; // initialize _method
log_info(verification)("Verifying method %s", m->name_and_sig_as_C_string());
// For clang, the only good constant format string is a literal constant format string.
#define bad_type_msg "Bad type on operand stack in %s"
int32_t max_stack = m->verifier_max_stack();
int32_t max_locals = m->max_locals();
constantPoolHandle cp(THREAD, m->constants());
// Method signature was checked in ClassFileParser.
assert(SignatureVerifier::is_valid_method_signature(m->signature()),
"Invalid method signature");
// Initial stack map frame: offset is 0, stack is initially empty.
StackMapFrame current_frame(max_locals, max_stack, this);
// Set initial locals
VerificationType return_type = current_frame.set_locals_from_arg(
m, current_type(), CHECK_VERIFY(this));
int32_t stackmap_index = 0; // index to the stackmap array
u4 code_length = m->code_size();
// Scan the bytecode and map each instruction's start offset to a number.
char* code_data = generate_code_data(m, code_length, CHECK_VERIFY(this));
int ex_min = code_length;
int ex_max = -1;
// Look through each item on the exception table. Each of the fields must refer
// to a legal instruction.
if (was_recursively_verified()) return;
verify_exception_handler_table(
code_length, code_data, ex_min, ex_max, CHECK_VERIFY(this));
// Look through each entry on the local variable table and make sure
// its range of code array offsets is valid. (4169817)
if (m->has_localvariable_table()) {
verify_local_variable_table(code_length, code_data, CHECK_VERIFY(this));
}
Array<u1>* stackmap_data = m->stackmap_data();
StackMapStream stream(stackmap_data);
StackMapReader reader(this, &stream, code_data, code_length, THREAD);
StackMapTable stackmap_table(&reader, ¤t_frame, max_locals, max_stack,
code_data, code_length, CHECK_VERIFY(this));
LogTarget(Info, verification) lt;
if (lt.is_enabled()) {
ResourceMark rm(THREAD);
LogStream ls(lt);
stackmap_table.print_on(&ls);
}
RawBytecodeStream bcs(m);
// Scan the byte code linearly from the start to the end
bool no_control_flow = false; // Set to true when there is no direct control
// flow from current instruction to the next
// instruction in sequence
Bytecodes::Code opcode;
while (!bcs.is_last_bytecode()) {
// Check for recursive re-verification before each bytecode.
if (was_recursively_verified()) return;
opcode = bcs.raw_next();
u2 bci = bcs.bci();
// Set current frame's offset to bci
current_frame.set_offset(bci);
current_frame.set_mark();
// Make sure every offset in stackmap table point to the beginning to
// an instruction. Match current_frame to stackmap_table entry with
// the same offset if exists.
stackmap_index = verify_stackmap_table(
stackmap_index, bci, ¤t_frame, &stackmap_table,
no_control_flow, CHECK_VERIFY(this));
bool this_uninit = false; // Set to true when invokespecial <init> initialized 'this'
bool verified_exc_handlers = false;
// Merge with the next instruction
{
u2 index;
int target;
VerificationType type, type2;
VerificationType atype;
LogTarget(Info, verification) lt;
if (lt.is_enabled()) {
ResourceMark rm(THREAD);
LogStream ls(lt);
current_frame.print_on(&ls);
lt.print("offset = %d, opcode = %s", bci,
opcode == Bytecodes::_illegal ? "illegal" : Bytecodes::name(opcode));
}
// Make sure wide instruction is in correct format
if (bcs.is_wide()) {
if (opcode != Bytecodes::_iinc && opcode != Bytecodes::_iload &&
opcode != Bytecodes::_aload && opcode != Bytecodes::_lload &&
opcode != Bytecodes::_istore && opcode != Bytecodes::_astore &&
opcode != Bytecodes::_lstore && opcode != Bytecodes::_fload &&
opcode != Bytecodes::_dload && opcode != Bytecodes::_fstore &&
opcode != Bytecodes::_dstore) {
/* Unreachable? RawBytecodeStream's raw_next() returns 'illegal'
* if we encounter a wide instruction that modifies an invalid
* opcode (not one of the ones listed above) */
verify_error(ErrorContext::bad_code(bci), "Bad wide instruction");
return;
}
}
// Look for possible jump target in exception handlers and see if it
// matches current_frame. Do this check here for astore*, dstore*,
// fstore*, istore*, and lstore* opcodes because they can change the type
// state by adding a local. JVM Spec says that the incoming type state
// should be used for this check. So, do the check here before a possible
// local is added to the type state.
if (Bytecodes::is_store_into_local(opcode) && bci >= ex_min && bci < ex_max) {
if (was_recursively_verified()) return;
verify_exception_handler_targets(
bci, this_uninit, ¤t_frame, &stackmap_table, CHECK_VERIFY(this));
verified_exc_handlers = true;
}
if (was_recursively_verified()) return;
switch (opcode) {
case Bytecodes::_nop :
no_control_flow = false; break;
case Bytecodes::_aconst_null :
current_frame.push_stack(
VerificationType::null_type(), CHECK_VERIFY(this));
no_control_flow = false; break;
case Bytecodes::_iconst_m1 :
case Bytecodes::_iconst_0 :
case Bytecodes::_iconst_1 :
case Bytecodes::_iconst_2 :
case Bytecodes::_iconst_3 :
case Bytecodes::_iconst_4 :
case Bytecodes::_iconst_5 :
current_frame.push_stack(
VerificationType::integer_type(), CHECK_VERIFY(this));
no_control_flow = false; break;
case Bytecodes::_lconst_0 :
case Bytecodes::_lconst_1 :
current_frame.push_stack_2(
VerificationType::long_type(),
VerificationType::long2_type(), CHECK_VERIFY(this));
no_control_flow = false; break;
case Bytecodes::_fconst_0 :
case Bytecodes::_fconst_1 :
case Bytecodes::_fconst_2 :
current_frame.push_stack(
VerificationType::float_type(), CHECK_VERIFY(this));
no_control_flow = false; break;
case Bytecodes::_dconst_0 :
case Bytecodes::_dconst_1 :
current_frame.push_stack_2(
VerificationType::double_type(),
VerificationType::double2_type(), CHECK_VERIFY(this));
no_control_flow = false; break;
case Bytecodes::_sipush :
case Bytecodes::_bipush :
current_frame.push_stack(
VerificationType::integer_type(), CHECK_VERIFY(this));
no_control_flow = false; break;
case Bytecodes::_ldc :
verify_ldc(
opcode, bcs.get_index_u1(), ¤t_frame,
cp, bci, CHECK_VERIFY(this));
no_control_flow = false; break;
case Bytecodes::_ldc_w :
case Bytecodes::_ldc2_w :
verify_ldc(
opcode, bcs.get_index_u2(), ¤t_frame,
cp, bci, CHECK_VERIFY(this));
no_control_flow = false; break;
case Bytecodes::_iload :
verify_iload(bcs.get_index(), ¤t_frame, CHECK_VERIFY(this));
no_control_flow = false; break;
case Bytecodes::_iload_0 :
case Bytecodes::_iload_1 :
case Bytecodes::_iload_2 :
case Bytecodes::_iload_3 :
index = opcode - Bytecodes::_iload_0;
verify_iload(index, ¤t_frame, CHECK_VERIFY(this));
no_control_flow = false; break;
case Bytecodes::_lload :
verify_lload(bcs.get_index(), ¤t_frame, CHECK_VERIFY(this));
no_control_flow = false; break;
case Bytecodes::_lload_0 :
case Bytecodes::_lload_1 :
case Bytecodes::_lload_2 :
case Bytecodes::_lload_3 :
index = opcode - Bytecodes::_lload_0;
verify_lload(index, ¤t_frame, CHECK_VERIFY(this));
no_control_flow = false; break;
case Bytecodes::_fload :
verify_fload(bcs.get_index(), ¤t_frame, CHECK_VERIFY(this));
no_control_flow = false; break;
case Bytecodes::_fload_0 :
case Bytecodes::_fload_1 :
case Bytecodes::_fload_2 :
case Bytecodes::_fload_3 :
index = opcode - Bytecodes::_fload_0;
verify_fload(index, ¤t_frame, CHECK_VERIFY(this));
no_control_flow = false; break;
case Bytecodes::_dload :
verify_dload(bcs.get_index(), ¤t_frame, CHECK_VERIFY(this));
no_control_flow = false; break;
case Bytecodes::_dload_0 :
case Bytecodes::_dload_1 :
case Bytecodes::_dload_2 :
case Bytecodes::_dload_3 :
index = opcode - Bytecodes::_dload_0;
verify_dload(index, ¤t_frame, CHECK_VERIFY(this));
no_control_flow = false; break;
case Bytecodes::_aload :
verify_aload(bcs.get_index(), ¤t_frame, CHECK_VERIFY(this));
no_control_flow = false; break;
case Bytecodes::_aload_0 :
case Bytecodes::_aload_1 :
case Bytecodes::_aload_2 :
case Bytecodes::_aload_3 :
index = opcode - Bytecodes::_aload_0;
verify_aload(index, ¤t_frame, CHECK_VERIFY(this));
no_control_flow = false; break;
case Bytecodes::_iaload :
type = current_frame.pop_stack(
VerificationType::integer_type(), CHECK_VERIFY(this));
atype = current_frame.pop_stack(
VerificationType::reference_check(), CHECK_VERIFY(this));
if (!atype.is_int_array()) {
verify_error(ErrorContext::bad_type(bci,
current_frame.stack_top_ctx(), ref_ctx("[I")),
bad_type_msg, "iaload");
return;
}
current_frame.push_stack(
VerificationType::integer_type(), CHECK_VERIFY(this));
no_control_flow = false; break;
case Bytecodes::_baload :
type = current_frame.pop_stack(
VerificationType::integer_type(), CHECK_VERIFY(this));
atype = current_frame.pop_stack(
VerificationType::reference_check(), CHECK_VERIFY(this));
if (!atype.is_bool_array() && !atype.is_byte_array()) {
verify_error(
ErrorContext::bad_type(bci, current_frame.stack_top_ctx()),
bad_type_msg, "baload");
return;
}
current_frame.push_stack(
VerificationType::integer_type(), CHECK_VERIFY(this));
no_control_flow = false; break;
case Bytecodes::_caload :
type = current_frame.pop_stack(
VerificationType::integer_type(), CHECK_VERIFY(this));
atype = current_frame.pop_stack(
VerificationType::reference_check(), CHECK_VERIFY(this));
if (!atype.is_char_array()) {
verify_error(ErrorContext::bad_type(bci,
current_frame.stack_top_ctx(), ref_ctx("[C")),
bad_type_msg, "caload");
return;
}
current_frame.push_stack(
VerificationType::integer_type(), CHECK_VERIFY(this));
no_control_flow = false; break;
case Bytecodes::_saload :
type = current_frame.pop_stack(
VerificationType::integer_type(), CHECK_VERIFY(this));
atype = current_frame.pop_stack(
VerificationType::reference_check(), CHECK_VERIFY(this));
if (!atype.is_short_array()) {
verify_error(ErrorContext::bad_type(bci,
current_frame.stack_top_ctx(), ref_ctx("[S")),
bad_type_msg, "saload");
return;
}
current_frame.push_stack(
VerificationType::integer_type(), CHECK_VERIFY(this));
no_control_flow = false; break;
case Bytecodes::_laload :
type = current_frame.pop_stack(
VerificationType::integer_type(), CHECK_VERIFY(this));
atype = current_frame.pop_stack(
VerificationType::reference_check(), CHECK_VERIFY(this));
if (!atype.is_long_array()) {
verify_error(ErrorContext::bad_type(bci,
current_frame.stack_top_ctx(), ref_ctx("[J")),
bad_type_msg, "laload");
return;
}
current_frame.push_stack_2(
VerificationType::long_type(),
VerificationType::long2_type(), CHECK_VERIFY(this));
no_control_flow = false; break;
case Bytecodes::_faload :
type = current_frame.pop_stack(
VerificationType::integer_type(), CHECK_VERIFY(this));
atype = current_frame.pop_stack(
VerificationType::reference_check(), CHECK_VERIFY(this));
if (!atype.is_float_array()) {
verify_error(ErrorContext::bad_type(bci,
current_frame.stack_top_ctx(), ref_ctx("[F")),
bad_type_msg, "faload");
return;
}
current_frame.push_stack(
VerificationType::float_type(), CHECK_VERIFY(this));
no_control_flow = false; break;
case Bytecodes::_daload :
type = current_frame.pop_stack(
VerificationType::integer_type(), CHECK_VERIFY(this));
atype = current_frame.pop_stack(
VerificationType::reference_check(), CHECK_VERIFY(this));
if (!atype.is_double_array()) {
verify_error(ErrorContext::bad_type(bci,
current_frame.stack_top_ctx(), ref_ctx("[D")),
bad_type_msg, "daload");
return;
}
current_frame.push_stack_2(
VerificationType::double_type(),
VerificationType::double2_type(), CHECK_VERIFY(this));
no_control_flow = false; break;
case Bytecodes::_aaload : {
type = current_frame.pop_stack(
VerificationType::integer_type(), CHECK_VERIFY(this));
atype = current_frame.pop_stack(
VerificationType::reference_check(), CHECK_VERIFY(this));
if (!atype.is_reference_array()) {
verify_error(ErrorContext::bad_type(bci,
current_frame.stack_top_ctx(),
TypeOrigin::implicit(VerificationType::reference_check())),
bad_type_msg, "aaload");
return;
}
if (atype.is_null()) {
current_frame.push_stack(
VerificationType::null_type(), CHECK_VERIFY(this));
} else {
VerificationType component =
atype.get_component(this, CHECK_VERIFY(this));
current_frame.push_stack(component, CHECK_VERIFY(this));
}
no_control_flow = false; break;
}
case Bytecodes::_istore :
verify_istore(bcs.get_index(), ¤t_frame, CHECK_VERIFY(this));
no_control_flow = false; break;
case Bytecodes::_istore_0 :
case Bytecodes::_istore_1 :
case Bytecodes::_istore_2 :
case Bytecodes::_istore_3 :
index = opcode - Bytecodes::_istore_0;
verify_istore(index, ¤t_frame, CHECK_VERIFY(this));
no_control_flow = false; break;
case Bytecodes::_lstore :
verify_lstore(bcs.get_index(), ¤t_frame, CHECK_VERIFY(this));
no_control_flow = false; break;
case Bytecodes::_lstore_0 :
case Bytecodes::_lstore_1 :
case Bytecodes::_lstore_2 :
case Bytecodes::_lstore_3 :
index = opcode - Bytecodes::_lstore_0;
verify_lstore(index, ¤t_frame, CHECK_VERIFY(this));
no_control_flow = false; break;
case Bytecodes::_fstore :
verify_fstore(bcs.get_index(), ¤t_frame, CHECK_VERIFY(this));
no_control_flow = false; break;
case Bytecodes::_fstore_0 :
case Bytecodes::_fstore_1 :
case Bytecodes::_fstore_2 :
case Bytecodes::_fstore_3 :
index = opcode - Bytecodes::_fstore_0;
verify_fstore(index, ¤t_frame, CHECK_VERIFY(this));
no_control_flow = false; break;
case Bytecodes::_dstore :
verify_dstore(bcs.get_index(), ¤t_frame, CHECK_VERIFY(this));
no_control_flow = false; break;
case Bytecodes::_dstore_0 :
case Bytecodes::_dstore_1 :
case Bytecodes::_dstore_2 :
case Bytecodes::_dstore_3 :
index = opcode - Bytecodes::_dstore_0;
verify_dstore(index, ¤t_frame, CHECK_VERIFY(this));
no_control_flow = false; break;
case Bytecodes::_astore :
verify_astore(bcs.get_index(), ¤t_frame, CHECK_VERIFY(this));
no_control_flow = false; break;
case Bytecodes::_astore_0 :
case Bytecodes::_astore_1 :
case Bytecodes::_astore_2 :
case Bytecodes::_astore_3 :
index = opcode - Bytecodes::_astore_0;
verify_astore(index, ¤t_frame, CHECK_VERIFY(this));
no_control_flow = false; break;
case Bytecodes::_iastore :
type = current_frame.pop_stack(
VerificationType::integer_type(), CHECK_VERIFY(this));
type2 = current_frame.pop_stack(
VerificationType::integer_type(), CHECK_VERIFY(this));
atype = current_frame.pop_stack(
VerificationType::reference_check(), CHECK_VERIFY(this));
if (!atype.is_int_array()) {
verify_error(ErrorContext::bad_type(bci,
current_frame.stack_top_ctx(), ref_ctx("[I")),
bad_type_msg, "iastore");
return;
}
no_control_flow = false; break;
case Bytecodes::_bastore :
type = current_frame.pop_stack(
VerificationType::integer_type(), CHECK_VERIFY(this));
type2 = current_frame.pop_stack(
VerificationType::integer_type(), CHECK_VERIFY(this));
atype = current_frame.pop_stack(
VerificationType::reference_check(), CHECK_VERIFY(this));
if (!atype.is_bool_array() && !atype.is_byte_array()) {
verify_error(
ErrorContext::bad_type(bci, current_frame.stack_top_ctx()),
bad_type_msg, "bastore");
return;
}
no_control_flow = false; break;
case Bytecodes::_castore :
current_frame.pop_stack(
VerificationType::integer_type(), CHECK_VERIFY(this));
current_frame.pop_stack(
VerificationType::integer_type(), CHECK_VERIFY(this));
atype = current_frame.pop_stack(
VerificationType::reference_check(), CHECK_VERIFY(this));
if (!atype.is_char_array()) {
verify_error(ErrorContext::bad_type(bci,
current_frame.stack_top_ctx(), ref_ctx("[C")),
bad_type_msg, "castore");
return;
}
no_control_flow = false; break;
case Bytecodes::_sastore :
current_frame.pop_stack(
VerificationType::integer_type(), CHECK_VERIFY(this));
current_frame.pop_stack(
VerificationType::integer_type(), CHECK_VERIFY(this));
atype = current_frame.pop_stack(
VerificationType::reference_check(), CHECK_VERIFY(this));
if (!atype.is_short_array()) {
verify_error(ErrorContext::bad_type(bci,
current_frame.stack_top_ctx(), ref_ctx("[S")),
bad_type_msg, "sastore");
return;
}
no_control_flow = false; break;
case Bytecodes::_lastore :
current_frame.pop_stack_2(
VerificationType::long2_type(),
VerificationType::long_type(), CHECK_VERIFY(this));
current_frame.pop_stack(
VerificationType::integer_type(), CHECK_VERIFY(this));
atype = current_frame.pop_stack(
VerificationType::reference_check(), CHECK_VERIFY(this));
if (!atype.is_long_array()) {
verify_error(ErrorContext::bad_type(bci,
current_frame.stack_top_ctx(), ref_ctx("[J")),
bad_type_msg, "lastore");
return;
}
no_control_flow = false; break;
case Bytecodes::_fastore :
current_frame.pop_stack(
VerificationType::float_type(), CHECK_VERIFY(this));
current_frame.pop_stack
(VerificationType::integer_type(), CHECK_VERIFY(this));
atype = current_frame.pop_stack(
VerificationType::reference_check(), CHECK_VERIFY(this));
if (!atype.is_float_array()) {
verify_error(ErrorContext::bad_type(bci,
current_frame.stack_top_ctx(), ref_ctx("[F")),
bad_type_msg, "fastore");
return;
}
no_control_flow = false; break;
case Bytecodes::_dastore :
current_frame.pop_stack_2(
VerificationType::double2_type(),
VerificationType::double_type(), CHECK_VERIFY(this));
current_frame.pop_stack(
VerificationType::integer_type(), CHECK_VERIFY(this));
atype = current_frame.pop_stack(
VerificationType::reference_check(), CHECK_VERIFY(this));
if (!atype.is_double_array()) {
verify_error(ErrorContext::bad_type(bci,
current_frame.stack_top_ctx(), ref_ctx("[D")),
bad_type_msg, "dastore");
return;
}
no_control_flow = false; break;
case Bytecodes::_aastore :
type = current_frame.pop_stack(object_type(), CHECK_VERIFY(this));
type2 = current_frame.pop_stack(
VerificationType::integer_type(), CHECK_VERIFY(this));
atype = current_frame.pop_stack(
VerificationType::reference_check(), CHECK_VERIFY(this));
// more type-checking is done at runtime
if (!atype.is_reference_array()) {
verify_error(ErrorContext::bad_type(bci,
current_frame.stack_top_ctx(),
TypeOrigin::implicit(VerificationType::reference_check())),
bad_type_msg, "aastore");
return;
}
// 4938384: relaxed constraint in JVMS 3nd edition.
no_control_flow = false; break;
case Bytecodes::_pop :
current_frame.pop_stack(
VerificationType::category1_check(), CHECK_VERIFY(this));
no_control_flow = false; break;
case Bytecodes::_pop2 :
type = current_frame.pop_stack(CHECK_VERIFY(this));
if (type.is_category1()) {
current_frame.pop_stack(
VerificationType::category1_check(), CHECK_VERIFY(this));
} else if (type.is_category2_2nd()) {
current_frame.pop_stack(
VerificationType::category2_check(), CHECK_VERIFY(this));
} else {
/* Unreachable? Would need a category2_1st on TOS
* which does not appear possible. */
verify_error(
ErrorContext::bad_type(bci, current_frame.stack_top_ctx()),
bad_type_msg, "pop2");
return;
}
no_control_flow = false; break;
case Bytecodes::_dup :
type = current_frame.pop_stack(
VerificationType::category1_check(), CHECK_VERIFY(this));
current_frame.push_stack(type, CHECK_VERIFY(this));
current_frame.push_stack(type, CHECK_VERIFY(this));
no_control_flow = false; break;
case Bytecodes::_dup_x1 :
type = current_frame.pop_stack(
VerificationType::category1_check(), CHECK_VERIFY(this));
type2 = current_frame.pop_stack(
VerificationType::category1_check(), CHECK_VERIFY(this));
current_frame.push_stack(type, CHECK_VERIFY(this));
current_frame.push_stack(type2, CHECK_VERIFY(this));
current_frame.push_stack(type, CHECK_VERIFY(this));
no_control_flow = false; break;
case Bytecodes::_dup_x2 :
{
VerificationType type3;
type = current_frame.pop_stack(
VerificationType::category1_check(), CHECK_VERIFY(this));
type2 = current_frame.pop_stack(CHECK_VERIFY(this));
if (type2.is_category1()) {
type3 = current_frame.pop_stack(
VerificationType::category1_check(), CHECK_VERIFY(this));
} else if (type2.is_category2_2nd()) {
type3 = current_frame.pop_stack(
VerificationType::category2_check(), CHECK_VERIFY(this));
} else {
/* Unreachable? Would need a category2_1st at stack depth 2 with
* a category1 on TOS which does not appear possible. */
verify_error(ErrorContext::bad_type(
bci, current_frame.stack_top_ctx()), bad_type_msg, "dup_x2");
return;
}
current_frame.push_stack(type, CHECK_VERIFY(this));
current_frame.push_stack(type3, CHECK_VERIFY(this));
current_frame.push_stack(type2, CHECK_VERIFY(this));
current_frame.push_stack(type, CHECK_VERIFY(this));
no_control_flow = false; break;
}
case Bytecodes::_dup2 :
type = current_frame.pop_stack(CHECK_VERIFY(this));
if (type.is_category1()) {
type2 = current_frame.pop_stack(
VerificationType::category1_check(), CHECK_VERIFY(this));
} else if (type.is_category2_2nd()) {
type2 = current_frame.pop_stack(
VerificationType::category2_check(), CHECK_VERIFY(this));
} else {
/* Unreachable? Would need a category2_1st on TOS which does not
* appear possible. */
verify_error(
ErrorContext::bad_type(bci, current_frame.stack_top_ctx()),
bad_type_msg, "dup2");
return;
}
current_frame.push_stack(type2, CHECK_VERIFY(this));
current_frame.push_stack(type, CHECK_VERIFY(this));
current_frame.push_stack(type2, CHECK_VERIFY(this));
current_frame.push_stack(type, CHECK_VERIFY(this));
no_control_flow = false; break;
case Bytecodes::_dup2_x1 :
{
VerificationType type3;
type = current_frame.pop_stack(CHECK_VERIFY(this));
if (type.is_category1()) {
type2 = current_frame.pop_stack(
VerificationType::category1_check(), CHECK_VERIFY(this));
} else if (type.is_category2_2nd()) {
type2 = current_frame.pop_stack(
VerificationType::category2_check(), CHECK_VERIFY(this));
} else {
/* Unreachable? Would need a category2_1st on TOS which does
* not appear possible. */
verify_error(
ErrorContext::bad_type(bci, current_frame.stack_top_ctx()),
bad_type_msg, "dup2_x1");
return;
}
type3 = current_frame.pop_stack(
VerificationType::category1_check(), CHECK_VERIFY(this));
current_frame.push_stack(type2, CHECK_VERIFY(this));
current_frame.push_stack(type, CHECK_VERIFY(this));
current_frame.push_stack(type3, CHECK_VERIFY(this));
current_frame.push_stack(type2, CHECK_VERIFY(this));
current_frame.push_stack(type, CHECK_VERIFY(this));
no_control_flow = false; break;
}
case Bytecodes::_dup2_x2 :
{
VerificationType type3, type4;
type = current_frame.pop_stack(CHECK_VERIFY(this));
if (type.is_category1()) {
type2 = current_frame.pop_stack(
VerificationType::category1_check(), CHECK_VERIFY(this));
} else if (type.is_category2_2nd()) {
type2 = current_frame.pop_stack(
VerificationType::category2_check(), CHECK_VERIFY(this));
} else {
/* Unreachable? Would need a category2_1st on TOS which does
* not appear possible. */
verify_error(
ErrorContext::bad_type(bci, current_frame.stack_top_ctx()),
bad_type_msg, "dup2_x2");
return;
}
type3 = current_frame.pop_stack(CHECK_VERIFY(this));
if (type3.is_category1()) {
type4 = current_frame.pop_stack(
VerificationType::category1_check(), CHECK_VERIFY(this));
} else if (type3.is_category2_2nd()) {
type4 = current_frame.pop_stack(
VerificationType::category2_check(), CHECK_VERIFY(this));
} else {
/* Unreachable? Would need a category2_1st on TOS after popping
* a long/double or two category 1's, which does not
* appear possible. */
verify_error(
ErrorContext::bad_type(bci, current_frame.stack_top_ctx()),
bad_type_msg, "dup2_x2");
return;
}
current_frame.push_stack(type2, CHECK_VERIFY(this));
current_frame.push_stack(type, CHECK_VERIFY(this));
current_frame.push_stack(type4, CHECK_VERIFY(this));
current_frame.push_stack(type3, CHECK_VERIFY(this));
current_frame.push_stack(type2, CHECK_VERIFY(this));
current_frame.push_stack(type, CHECK_VERIFY(this));
no_control_flow = false; break;
}
case Bytecodes::_swap :
type = current_frame.pop_stack(
VerificationType::category1_check(), CHECK_VERIFY(this));
type2 = current_frame.pop_stack(
VerificationType::category1_check(), CHECK_VERIFY(this));
current_frame.push_stack(type, CHECK_VERIFY(this));
current_frame.push_stack(type2, CHECK_VERIFY(this));
no_control_flow = false; break;
case Bytecodes::_iadd :
case Bytecodes::_isub :
case Bytecodes::_imul :
case Bytecodes::_idiv :
case Bytecodes::_irem :
case Bytecodes::_ishl :
case Bytecodes::_ishr :
case Bytecodes::_iushr :
case Bytecodes::_ior :
case Bytecodes::_ixor :
case Bytecodes::_iand :
current_frame.pop_stack(
VerificationType::integer_type(), CHECK_VERIFY(this));
// fall through
case Bytecodes::_ineg :
current_frame.pop_stack(
VerificationType::integer_type(), CHECK_VERIFY(this));
current_frame.push_stack(
VerificationType::integer_type(), CHECK_VERIFY(this));
no_control_flow = false; break;
case Bytecodes::_ladd :
case Bytecodes::_lsub :
case Bytecodes::_lmul :
case Bytecodes::_ldiv :
case Bytecodes::_lrem :
case Bytecodes::_land :
case Bytecodes::_lor :
case Bytecodes::_lxor :
current_frame.pop_stack_2(
VerificationType::long2_type(),
VerificationType::long_type(), CHECK_VERIFY(this));
// fall through
case Bytecodes::_lneg :
current_frame.pop_stack_2(
VerificationType::long2_type(),
VerificationType::long_type(), CHECK_VERIFY(this));
current_frame.push_stack_2(
VerificationType::long_type(),
VerificationType::long2_type(), CHECK_VERIFY(this));
no_control_flow = false; break;
case Bytecodes::_lshl :
case Bytecodes::_lshr :
case Bytecodes::_lushr :
current_frame.pop_stack(
VerificationType::integer_type(), CHECK_VERIFY(this));
current_frame.pop_stack_2(
VerificationType::long2_type(),
VerificationType::long_type(), CHECK_VERIFY(this));
current_frame.push_stack_2(
VerificationType::long_type(),
VerificationType::long2_type(), CHECK_VERIFY(this));
no_control_flow = false; break;
case Bytecodes::_fadd :
case Bytecodes::_fsub :
case Bytecodes::_fmul :
case Bytecodes::_fdiv :
case Bytecodes::_frem :
current_frame.pop_stack(
VerificationType::float_type(), CHECK_VERIFY(this));
// fall through
case Bytecodes::_fneg :
current_frame.pop_stack(
VerificationType::float_type(), CHECK_VERIFY(this));
current_frame.push_stack(
VerificationType::float_type(), CHECK_VERIFY(this));
no_control_flow = false; break;
case Bytecodes::_dadd :
case Bytecodes::_dsub :
case Bytecodes::_dmul :
case Bytecodes::_ddiv :
case Bytecodes::_drem :
current_frame.pop_stack_2(
VerificationType::double2_type(),
VerificationType::double_type(), CHECK_VERIFY(this));
// fall through
case Bytecodes::_dneg :
current_frame.pop_stack_2(
VerificationType::double2_type(),
VerificationType::double_type(), CHECK_VERIFY(this));
current_frame.push_stack_2(
VerificationType::double_type(),
VerificationType::double2_type(), CHECK_VERIFY(this));
no_control_flow = false; break;
case Bytecodes::_iinc :
verify_iinc(bcs.get_index(), ¤t_frame, CHECK_VERIFY(this));
no_control_flow = false; break;
case Bytecodes::_i2l :
type = current_frame.pop_stack(
VerificationType::integer_type(), CHECK_VERIFY(this));
current_frame.push_stack_2(
VerificationType::long_type(),
VerificationType::long2_type(), CHECK_VERIFY(this));
no_control_flow = false; break;
case Bytecodes::_l2i :
current_frame.pop_stack_2(
VerificationType::long2_type(),
VerificationType::long_type(), CHECK_VERIFY(this));
current_frame.push_stack(
VerificationType::integer_type(), CHECK_VERIFY(this));
no_control_flow = false; break;
case Bytecodes::_i2f :
current_frame.pop_stack(
VerificationType::integer_type(), CHECK_VERIFY(this));
current_frame.push_stack(
VerificationType::float_type(), CHECK_VERIFY(this));
no_control_flow = false; break;
case Bytecodes::_i2d :
current_frame.pop_stack(
VerificationType::integer_type(), CHECK_VERIFY(this));
current_frame.push_stack_2(
VerificationType::double_type(),
VerificationType::double2_type(), CHECK_VERIFY(this));
no_control_flow = false; break;
case Bytecodes::_l2f :
current_frame.pop_stack_2(
VerificationType::long2_type(),
VerificationType::long_type(), CHECK_VERIFY(this));
current_frame.push_stack(
VerificationType::float_type(), CHECK_VERIFY(this));
no_control_flow = false; break;
case Bytecodes::_l2d :
current_frame.pop_stack_2(
VerificationType::long2_type(),
VerificationType::long_type(), CHECK_VERIFY(this));
current_frame.push_stack_2(
VerificationType::double_type(),
VerificationType::double2_type(), CHECK_VERIFY(this));
no_control_flow = false; break;
case Bytecodes::_f2i :
current_frame.pop_stack(
VerificationType::float_type(), CHECK_VERIFY(this));
current_frame.push_stack(
VerificationType::integer_type(), CHECK_VERIFY(this));
no_control_flow = false; break;
case Bytecodes::_f2l :
current_frame.pop_stack(
VerificationType::float_type(), CHECK_VERIFY(this));
current_frame.push_stack_2(
VerificationType::long_type(),
VerificationType::long2_type(), CHECK_VERIFY(this));
no_control_flow = false; break;
case Bytecodes::_f2d :
current_frame.pop_stack(
VerificationType::float_type(), CHECK_VERIFY(this));
current_frame.push_stack_2(
VerificationType::double_type(),
VerificationType::double2_type(), CHECK_VERIFY(this));
no_control_flow = false; break;
case Bytecodes::_d2i :
current_frame.pop_stack_2(
VerificationType::double2_type(),
VerificationType::double_type(), CHECK_VERIFY(this));
current_frame.push_stack(
VerificationType::integer_type(), CHECK_VERIFY(this));
no_control_flow = false; break;
case Bytecodes::_d2l :
current_frame.pop_stack_2(
VerificationType::double2_type(),
VerificationType::double_type(), CHECK_VERIFY(this));
current_frame.push_stack_2(
VerificationType::long_type(),
VerificationType::long2_type(), CHECK_VERIFY(this));
no_control_flow = false; break;
case Bytecodes::_d2f :
current_frame.pop_stack_2(
VerificationType::double2_type(),
VerificationType::double_type(), CHECK_VERIFY(this));
current_frame.push_stack(
VerificationType::float_type(), CHECK_VERIFY(this));
no_control_flow = false; break;
case Bytecodes::_i2b :
case Bytecodes::_i2c :
case Bytecodes::_i2s :
current_frame.pop_stack(
VerificationType::integer_type(), CHECK_VERIFY(this));
current_frame.push_stack(
VerificationType::integer_type(), CHECK_VERIFY(this));
no_control_flow = false; break;
case Bytecodes::_lcmp :
current_frame.pop_stack_2(
VerificationType::long2_type(),
VerificationType::long_type(), CHECK_VERIFY(this));
current_frame.pop_stack_2(
VerificationType::long2_type(),
VerificationType::long_type(), CHECK_VERIFY(this));
current_frame.push_stack(
VerificationType::integer_type(), CHECK_VERIFY(this));
no_control_flow = false; break;
case Bytecodes::_fcmpl :
case Bytecodes::_fcmpg :
current_frame.pop_stack(
VerificationType::float_type(), CHECK_VERIFY(this));
current_frame.pop_stack(
VerificationType::float_type(), CHECK_VERIFY(this));
current_frame.push_stack(
VerificationType::integer_type(), CHECK_VERIFY(this));
no_control_flow = false; break;
case Bytecodes::_dcmpl :
case Bytecodes::_dcmpg :
current_frame.pop_stack_2(
VerificationType::double2_type(),
VerificationType::double_type(), CHECK_VERIFY(this));
current_frame.pop_stack_2(
VerificationType::double2_type(),
VerificationType::double_type(), CHECK_VERIFY(this));
current_frame.push_stack(
VerificationType::integer_type(), CHECK_VERIFY(this));
no_control_flow = false; break;
case Bytecodes::_if_icmpeq:
case Bytecodes::_if_icmpne:
case Bytecodes::_if_icmplt:
case Bytecodes::_if_icmpge:
case Bytecodes::_if_icmpgt:
case Bytecodes::_if_icmple:
current_frame.pop_stack(
VerificationType::integer_type(), CHECK_VERIFY(this));
// fall through
case Bytecodes::_ifeq:
case Bytecodes::_ifne:
case Bytecodes::_iflt:
case Bytecodes::_ifge:
case Bytecodes::_ifgt:
case Bytecodes::_ifle:
current_frame.pop_stack(
VerificationType::integer_type(), CHECK_VERIFY(this));
target = bcs.dest();
stackmap_table.check_jump_target(
¤t_frame, target, CHECK_VERIFY(this));
no_control_flow = false; break;
case Bytecodes::_if_acmpeq :
case Bytecodes::_if_acmpne :
current_frame.pop_stack(
VerificationType::reference_check(), CHECK_VERIFY(this));
// fall through
case Bytecodes::_ifnull :
case Bytecodes::_ifnonnull :
current_frame.pop_stack(
VerificationType::reference_check(), CHECK_VERIFY(this));
target = bcs.dest();
stackmap_table.check_jump_target
(¤t_frame, target, CHECK_VERIFY(this));
no_control_flow = false; break;
case Bytecodes::_goto :
target = bcs.dest();
stackmap_table.check_jump_target(
¤t_frame, target, CHECK_VERIFY(this));
no_control_flow = true; break;
case Bytecodes::_goto_w :
target = bcs.dest_w();
stackmap_table.check_jump_target(
¤t_frame, target, CHECK_VERIFY(this));
no_control_flow = true; break;
case Bytecodes::_tableswitch :
case Bytecodes::_lookupswitch :
verify_switch(
&bcs, code_length, code_data, ¤t_frame,
&stackmap_table, CHECK_VERIFY(this));
no_control_flow = true; break;
case Bytecodes::_ireturn :
type = current_frame.pop_stack(
VerificationType::integer_type(), CHECK_VERIFY(this));
verify_return_value(return_type, type, bci,
¤t_frame, CHECK_VERIFY(this));
no_control_flow = true; break;
case Bytecodes::_lreturn :
type2 = current_frame.pop_stack(
VerificationType::long2_type(), CHECK_VERIFY(this));
type = current_frame.pop_stack(
VerificationType::long_type(), CHECK_VERIFY(this));
verify_return_value(return_type, type, bci,
¤t_frame, CHECK_VERIFY(this));
no_control_flow = true; break;
case Bytecodes::_freturn :
type = current_frame.pop_stack(
VerificationType::float_type(), CHECK_VERIFY(this));
verify_return_value(return_type, type, bci,
¤t_frame, CHECK_VERIFY(this));
no_control_flow = true; break;
case Bytecodes::_dreturn :
type2 = current_frame.pop_stack(
VerificationType::double2_type(), CHECK_VERIFY(this));
type = current_frame.pop_stack(
VerificationType::double_type(), CHECK_VERIFY(this));
verify_return_value(return_type, type, bci,
¤t_frame, CHECK_VERIFY(this));
no_control_flow = true; break;
case Bytecodes::_areturn :
type = current_frame.pop_stack(
VerificationType::reference_check(), CHECK_VERIFY(this));
verify_return_value(return_type, type, bci,
¤t_frame, CHECK_VERIFY(this));
no_control_flow = true; break;
case Bytecodes::_return :
if (return_type != VerificationType::bogus_type()) {
verify_error(ErrorContext::bad_code(bci),
"Method expects a return value");
return;
}
// Make sure "this" has been initialized if current method is an
// <init>.
if (_method->name() == vmSymbols::object_initializer_name() &&
current_frame.flag_this_uninit()) {
verify_error(ErrorContext::bad_code(bci),
"Constructor must call super() or this() "
"before return");
return;
}
no_control_flow = true; break;
case Bytecodes::_getstatic :
case Bytecodes::_putstatic :
// pass TRUE, operand can be an array type for getstatic/putstatic.
verify_field_instructions(
&bcs, ¤t_frame, cp, true, CHECK_VERIFY(this));
no_control_flow = false; break;
case Bytecodes::_getfield :
case Bytecodes::_putfield :
// pass FALSE, operand can't be an array type for getfield/putfield.
verify_field_instructions(
&bcs, ¤t_frame, cp, false, CHECK_VERIFY(this));
no_control_flow = false; break;
case Bytecodes::_invokevirtual :
case Bytecodes::_invokespecial :
case Bytecodes::_invokestatic :
verify_invoke_instructions(
&bcs, code_length, ¤t_frame, (bci >= ex_min && bci < ex_max),
&this_uninit, return_type, cp, &stackmap_table, CHECK_VERIFY(this));
no_control_flow = false; break;
case Bytecodes::_invokeinterface :
case Bytecodes::_invokedynamic :
verify_invoke_instructions(
&bcs, code_length, ¤t_frame, (bci >= ex_min && bci < ex_max),
&this_uninit, return_type, cp, &stackmap_table, CHECK_VERIFY(this));
no_control_flow = false; break;
case Bytecodes::_new :
{
index = bcs.get_index_u2();
verify_cp_class_type(bci, index, cp, CHECK_VERIFY(this));
VerificationType new_class_type =
cp_index_to_type(index, cp, CHECK_VERIFY(this));
if (!new_class_type.is_object()) {
verify_error(ErrorContext::bad_type(bci,
TypeOrigin::cp(index, new_class_type)),
"Illegal new instruction");
return;
}
type = VerificationType::uninitialized_type(bci);
current_frame.push_stack(type, CHECK_VERIFY(this));
no_control_flow = false; break;
}
case Bytecodes::_newarray :
type = get_newarray_type(bcs.get_index(), bci, CHECK_VERIFY(this));
current_frame.pop_stack(
VerificationType::integer_type(), CHECK_VERIFY(this));
current_frame.push_stack(type, CHECK_VERIFY(this));
no_control_flow = false; break;
case Bytecodes::_anewarray :
verify_anewarray(
bci, bcs.get_index_u2(), cp, ¤t_frame, CHECK_VERIFY(this));
no_control_flow = false; break;
case Bytecodes::_arraylength :
type = current_frame.pop_stack(
VerificationType::reference_check(), CHECK_VERIFY(this));
if (!(type.is_null() || type.is_array())) {
verify_error(ErrorContext::bad_type(
bci, current_frame.stack_top_ctx()),
bad_type_msg, "arraylength");
}
current_frame.push_stack(
VerificationType::integer_type(), CHECK_VERIFY(this));
no_control_flow = false; break;
case Bytecodes::_checkcast :
{
index = bcs.get_index_u2();
verify_cp_class_type(bci, index, cp, CHECK_VERIFY(this));
current_frame.pop_stack(object_type(), CHECK_VERIFY(this));
VerificationType klass_type = cp_index_to_type(
index, cp, CHECK_VERIFY(this));
current_frame.push_stack(klass_type, CHECK_VERIFY(this));
no_control_flow = false; break;
}
case Bytecodes::_instanceof : {
index = bcs.get_index_u2();
verify_cp_class_type(bci, index, cp, CHECK_VERIFY(this));
current_frame.pop_stack(object_type(), CHECK_VERIFY(this));
current_frame.push_stack(
VerificationType::integer_type(), CHECK_VERIFY(this));
no_control_flow = false; break;
}
case Bytecodes::_monitorenter :
case Bytecodes::_monitorexit :
current_frame.pop_stack(
VerificationType::reference_check(), CHECK_VERIFY(this));
no_control_flow = false; break;
case Bytecodes::_multianewarray :
{
index = bcs.get_index_u2();
u2 dim = *(bcs.bcp()+3);
verify_cp_class_type(bci, index, cp, CHECK_VERIFY(this));
VerificationType new_array_type =
cp_index_to_type(index, cp, CHECK_VERIFY(this));
if (!new_array_type.is_array()) {
verify_error(ErrorContext::bad_type(bci,
TypeOrigin::cp(index, new_array_type)),
"Illegal constant pool index in multianewarray instruction");
return;
}
if (dim < 1 || new_array_type.dimensions() < dim) {
verify_error(ErrorContext::bad_code(bci),
"Illegal dimension in multianewarray instruction: %d", dim);
return;
}
for (int i = 0; i < dim; i++) {
current_frame.pop_stack(
VerificationType::integer_type(), CHECK_VERIFY(this));
}
current_frame.push_stack(new_array_type, CHECK_VERIFY(this));
no_control_flow = false; break;
}
case Bytecodes::_athrow :
type = VerificationType::reference_type(
vmSymbols::java_lang_Throwable());
current_frame.pop_stack(type, CHECK_VERIFY(this));
no_control_flow = true; break;
default:
// We only need to check the valid bytecodes in class file.
// And jsr and ret are not in the new class file format in JDK1.5.
verify_error(ErrorContext::bad_code(bci),
"Bad instruction: %02x", opcode);
no_control_flow = false;
return;
} // end switch
} // end Merge with the next instruction
// Look for possible jump target in exception handlers and see if it matches
// current_frame. Don't do this check if it has already been done (for
// ([a,d,f,i,l]store* opcodes). This check cannot be done earlier because
// opcodes, such as invokespecial, may set the this_uninit flag.
assert(!(verified_exc_handlers && this_uninit),
"Exception handler targets got verified before this_uninit got set");
if (!verified_exc_handlers && bci >= ex_min && bci < ex_max) {
if (was_recursively_verified()) return;
verify_exception_handler_targets(
bci, this_uninit, ¤t_frame, &stackmap_table, CHECK_VERIFY(this));
}
} // end while
// Make sure that control flow does not fall through end of the method
if (!no_control_flow) {
verify_error(ErrorContext::bad_code(code_length),
"Control flow falls through code end");
return;
}
}
#undef bad_type_message
char* ClassVerifier::generate_code_data(const methodHandle& m, u4 code_length, TRAPS) {
char* code_data = NEW_RESOURCE_ARRAY(char, code_length);
memset(code_data, 0, sizeof(char) * code_length);
RawBytecodeStream bcs(m);
while (!bcs.is_last_bytecode()) {
if (bcs.raw_next() != Bytecodes::_illegal) {
int bci = bcs.bci();
if (bcs.raw_code() == Bytecodes::_new) {
code_data[bci] = NEW_OFFSET;
} else {
code_data[bci] = BYTECODE_OFFSET;
}
} else {
verify_error(ErrorContext::bad_code(bcs.bci()), "Bad instruction");
return NULL;
}
}
return code_data;
}
// Since this method references the constant pool, call was_recursively_verified()
// before calling this method to make sure a prior class load did not cause the
// current class to get verified.
void ClassVerifier::verify_exception_handler_table(u4 code_length, char* code_data, int& min, int& max, TRAPS) {
ExceptionTable exhandlers(_method());
int exlength = exhandlers.length();
constantPoolHandle cp (THREAD, _method->constants());
for(int i = 0; i < exlength; i++) {
u2 start_pc = exhandlers.start_pc(i);
u2 end_pc = exhandlers.end_pc(i);
u2 handler_pc = exhandlers.handler_pc(i);
if (start_pc >= code_length || code_data[start_pc] == 0) {
class_format_error("Illegal exception table start_pc %d", start_pc);
return;
}
if (end_pc != code_length) { // special case: end_pc == code_length
if (end_pc > code_length || code_data[end_pc] == 0) {
class_format_error("Illegal exception table end_pc %d", end_pc);
return;
}
}
if (handler_pc >= code_length || code_data[handler_pc] == 0) {
class_format_error("Illegal exception table handler_pc %d", handler_pc);
return;
}
int catch_type_index = exhandlers.catch_type_index(i);
if (catch_type_index != 0) {
VerificationType catch_type = cp_index_to_type(
catch_type_index, cp, CHECK_VERIFY(this));
VerificationType throwable =
VerificationType::reference_type(vmSymbols::java_lang_Throwable());
bool is_subclass = throwable.is_assignable_from(
catch_type, this, false, CHECK_VERIFY(this));
if (!is_subclass) {
// 4286534: should throw VerifyError according to recent spec change
verify_error(ErrorContext::bad_type(handler_pc,
TypeOrigin::cp(catch_type_index, catch_type),
TypeOrigin::implicit(throwable)),
"Catch type is not a subclass "
"of Throwable in exception handler %d", handler_pc);
return;
}
}
if (start_pc < min) min = start_pc;
if (end_pc > max) max = end_pc;
}
}
void ClassVerifier::verify_local_variable_table(u4 code_length, char* code_data, TRAPS) {
int localvariable_table_length = _method->localvariable_table_length();
if (localvariable_table_length > 0) {
LocalVariableTableElement* table = _method->localvariable_table_start();
for (int i = 0; i < localvariable_table_length; i++) {
u2 start_bci = table[i].start_bci;
u2 length = table[i].length;
if (start_bci >= code_length || code_data[start_bci] == 0) {
class_format_error(
"Illegal local variable table start_pc %d", start_bci);
return;
}
u4 end_bci = (u4)(start_bci + length);
if (end_bci != code_length) {
if (end_bci >= code_length || code_data[end_bci] == 0) {
class_format_error( "Illegal local variable table length %d", length);
return;
}
}
}
}
}
u2 ClassVerifier::verify_stackmap_table(u2 stackmap_index, u2 bci,
StackMapFrame* current_frame,
StackMapTable* stackmap_table,
bool no_control_flow, TRAPS) {
if (stackmap_index < stackmap_table->get_frame_count()) {
u2 this_offset = stackmap_table->get_offset(stackmap_index);
if (no_control_flow && this_offset > bci) {
verify_error(ErrorContext::missing_stackmap(bci),
"Expecting a stack map frame");
return 0;
}
if (this_offset == bci) {
ErrorContext ctx;
// See if current stack map can be assigned to the frame in table.
// current_frame is the stackmap frame got from the last instruction.
// If matched, current_frame will be updated by this method.
bool matches = stackmap_table->match_stackmap(
current_frame, this_offset, stackmap_index,
!no_control_flow, true, &ctx, CHECK_VERIFY_(this, 0));
if (!matches) {
// report type error
verify_error(ctx, "Instruction type does not match stack map");
return 0;
}
stackmap_index++;
} else if (this_offset < bci) {
// current_offset should have met this_offset.
class_format_error("Bad stack map offset %d", this_offset);
return 0;
}
} else if (no_control_flow) {
verify_error(ErrorContext::bad_code(bci), "Expecting a stack map frame");
return 0;
}
return stackmap_index;
}
// Since this method references the constant pool, call was_recursively_verified()
// before calling this method to make sure a prior class load did not cause the
// current class to get verified.
void ClassVerifier::verify_exception_handler_targets(u2 bci, bool this_uninit,
StackMapFrame* current_frame,
StackMapTable* stackmap_table, TRAPS) {
constantPoolHandle cp (THREAD, _method->constants());
ExceptionTable exhandlers(_method());
int exlength = exhandlers.length();
for(int i = 0; i < exlength; i++) {
u2 start_pc = exhandlers.start_pc(i);
u2 end_pc = exhandlers.end_pc(i);
u2 handler_pc = exhandlers.handler_pc(i);
int catch_type_index = exhandlers.catch_type_index(i);
if(bci >= start_pc && bci < end_pc) {
u1 flags = current_frame->flags();
if (this_uninit) { flags |= FLAG_THIS_UNINIT; }
StackMapFrame* new_frame = current_frame->frame_in_exception_handler(flags);
if (catch_type_index != 0) {
if (was_recursively_verified()) return;
// We know that this index refers to a subclass of Throwable
VerificationType catch_type = cp_index_to_type(
catch_type_index, cp, CHECK_VERIFY(this));
new_frame->push_stack(catch_type, CHECK_VERIFY(this));
} else {
VerificationType throwable =
VerificationType::reference_type(vmSymbols::java_lang_Throwable());
new_frame->push_stack(throwable, CHECK_VERIFY(this));
}
ErrorContext ctx;
bool matches = stackmap_table->match_stackmap(
new_frame, handler_pc, true, false, &ctx, CHECK_VERIFY(this));
if (!matches) {
verify_error(ctx, "Stack map does not match the one at "
"exception handler %d", handler_pc);
return;
}
}
}
}
void ClassVerifier::verify_cp_index(
u2 bci, const constantPoolHandle& cp, int index, TRAPS) {
int nconstants = cp->length();
if ((index <= 0) || (index >= nconstants)) {
verify_error(ErrorContext::bad_cp_index(bci, index),
"Illegal constant pool index %d in class %s",
index, cp->pool_holder()->external_name());
return;
}
}
void ClassVerifier::verify_cp_type(
u2 bci, int index, const constantPoolHandle& cp, unsigned int types, TRAPS) {
// In some situations, bytecode rewriting may occur while we're verifying.
// In this case, a constant pool cache exists and some indices refer to that
// instead. Be sure we don't pick up such indices by accident.
// We must check was_recursively_verified() before we get here.
guarantee(cp->cache() == NULL, "not rewritten yet");
verify_cp_index(bci, cp, index, CHECK_VERIFY(this));
unsigned int tag = cp->tag_at(index).value();
if ((types & (1 << tag)) == 0) {
verify_error(ErrorContext::bad_cp_index(bci, index),
"Illegal type at constant pool entry %d in class %s",
index, cp->pool_holder()->external_name());
return;
}
}
void ClassVerifier::verify_cp_class_type(
u2 bci, int index, const constantPoolHandle& cp, TRAPS) {
verify_cp_index(bci, cp, index, CHECK_VERIFY(this));
constantTag tag = cp->tag_at(index);
if (!tag.is_klass() && !tag.is_unresolved_klass()) {
verify_error(ErrorContext::bad_cp_index(bci, index),
"Illegal type at constant pool entry %d in class %s",
index, cp->pool_holder()->external_name());
return;
}
}
void ClassVerifier::verify_error(ErrorContext ctx, const char* msg, ...) {
stringStream ss;
ctx.reset_frames();
_exception_type = vmSymbols::java_lang_VerifyError();
_error_context = ctx;
va_list va;
va_start(va, msg);
ss.vprint(msg, va);
va_end(va);
_message = ss.as_string();
#ifdef ASSERT
ResourceMark rm;
const char* exception_name = _exception_type->as_C_string();
Exceptions::debug_check_abort(exception_name, NULL);
#endif // ndef ASSERT
}
void ClassVerifier::class_format_error(const char* msg, ...) {
stringStream ss;
_exception_type = vmSymbols::java_lang_ClassFormatError();
va_list va;
va_start(va, msg);
ss.vprint(msg, va);
va_end(va);
if (!_method.is_null()) {
ss.print(" in method '");
_method->print_external_name(&ss);
ss.print("'");
}
_message = ss.as_string();
}
Klass* ClassVerifier::load_class(Symbol* name, TRAPS) {
HandleMark hm(THREAD);
// Get current loader and protection domain first.
oop loader = current_class()->class_loader();
oop protection_domain = current_class()->protection_domain();
Klass* kls = SystemDictionary::resolve_or_fail(
name, Handle(THREAD, loader), Handle(THREAD, protection_domain),
true, THREAD);
if (kls != NULL) {
if (log_is_enabled(Debug, class, resolve)) {
Verifier::trace_class_resolution(kls, current_class());
}
}
return kls;
}
bool ClassVerifier::is_protected_access(InstanceKlass* this_class,
Klass* target_class,
Symbol* field_name,
Symbol* field_sig,
bool is_method) {
NoSafepointVerifier nosafepoint;
// If target class isn't a super class of this class, we don't worry about this case
if (!this_class->is_subclass_of(target_class)) {
return false;
}
// Check if the specified method or field is protected
InstanceKlass* target_instance = InstanceKlass::cast(target_class);
fieldDescriptor fd;
if (is_method) {
Method* m = target_instance->uncached_lookup_method(field_name, field_sig, Klass::find_overpass);
if (m != NULL && m->is_protected()) {
if (!this_class->is_same_class_package(m->method_holder())) {
return true;
}
}
} else {
Klass* member_klass = target_instance->find_field(field_name, field_sig, &fd);
if (member_klass != NULL && fd.is_protected()) {
if (!this_class->is_same_class_package(member_klass)) {
return true;
}
}
}
return false;
}
void ClassVerifier::verify_ldc(
int opcode, u2 index, StackMapFrame* current_frame,
const constantPoolHandle& cp, u2 bci, TRAPS) {
verify_cp_index(bci, cp, index, CHECK_VERIFY(this));
constantTag tag = cp->tag_at(index);
unsigned int types = 0;
if (opcode == Bytecodes::_ldc || opcode == Bytecodes::_ldc_w) {
if (!tag.is_unresolved_klass()) {
types = (1 << JVM_CONSTANT_Integer) | (1 << JVM_CONSTANT_Float)
| (1 << JVM_CONSTANT_String) | (1 << JVM_CONSTANT_Class)
| (1 << JVM_CONSTANT_MethodHandle) | (1 << JVM_CONSTANT_MethodType)
| (1 << JVM_CONSTANT_Dynamic);
// Note: The class file parser already verified the legality of
// MethodHandle and MethodType constants.
verify_cp_type(bci, index, cp, types, CHECK_VERIFY(this));
}
} else {
assert(opcode == Bytecodes::_ldc2_w, "must be ldc2_w");
types = (1 << JVM_CONSTANT_Double) | (1 << JVM_CONSTANT_Long)
| (1 << JVM_CONSTANT_Dynamic);
verify_cp_type(bci, index, cp, types, CHECK_VERIFY(this));
}
if (tag.is_string() && cp->is_pseudo_string_at(index)) {
current_frame->push_stack(object_type(), CHECK_VERIFY(this));
} else if (tag.is_string()) {
current_frame->push_stack(
VerificationType::reference_type(
vmSymbols::java_lang_String()), CHECK_VERIFY(this));
} else if (tag.is_klass() || tag.is_unresolved_klass()) {
current_frame->push_stack(
VerificationType::reference_type(
vmSymbols::java_lang_Class()), CHECK_VERIFY(this));
} else if (tag.is_int()) {
current_frame->push_stack(
VerificationType::integer_type(), CHECK_VERIFY(this));
} else if (tag.is_float()) {
current_frame->push_stack(
VerificationType::float_type(), CHECK_VERIFY(this));
} else if (tag.is_double()) {
current_frame->push_stack_2(
VerificationType::double_type(),
VerificationType::double2_type(), CHECK_VERIFY(this));
} else if (tag.is_long()) {
current_frame->push_stack_2(
VerificationType::long_type(),
VerificationType::long2_type(), CHECK_VERIFY(this));
} else if (tag.is_method_handle()) {
current_frame->push_stack(
VerificationType::reference_type(
vmSymbols::java_lang_invoke_MethodHandle()), CHECK_VERIFY(this));
} else if (tag.is_method_type()) {
current_frame->push_stack(
VerificationType::reference_type(
vmSymbols::java_lang_invoke_MethodType()), CHECK_VERIFY(this));
} else if (tag.is_dynamic_constant()) {
Symbol* constant_type = cp->uncached_signature_ref_at(index);
// Field signature was checked in ClassFileParser.
assert(SignatureVerifier::is_valid_type_signature(constant_type),
"Invalid type for dynamic constant");
assert(sizeof(VerificationType) == sizeof(uintptr_t),
"buffer type must match VerificationType size");
uintptr_t constant_type_buffer[2];
VerificationType* v_constant_type = (VerificationType*)constant_type_buffer;
SignatureStream sig_stream(constant_type, false);
int n = change_sig_to_verificationType(&sig_stream, v_constant_type);
int opcode_n = (opcode == Bytecodes::_ldc2_w ? 2 : 1);
if (n != opcode_n) {
// wrong kind of ldc; reverify against updated type mask
types &= ~(1 << JVM_CONSTANT_Dynamic);
verify_cp_type(bci, index, cp, types, CHECK_VERIFY(this));
}
for (int i = 0; i < n; i++) {
current_frame->push_stack(v_constant_type[i], CHECK_VERIFY(this));
}
} else {
/* Unreachable? verify_cp_type has already validated the cp type. */
verify_error(
ErrorContext::bad_cp_index(bci, index), "Invalid index in ldc");
return;
}
}
void ClassVerifier::verify_switch(
RawBytecodeStream* bcs, u4 code_length, char* code_data,
StackMapFrame* current_frame, StackMapTable* stackmap_table, TRAPS) {
int bci = bcs->bci();
address bcp = bcs->bcp();
address aligned_bcp = align_up(bcp + 1, jintSize);
if (_klass->major_version() < NONZERO_PADDING_BYTES_IN_SWITCH_MAJOR_VERSION) {
// 4639449 & 4647081: padding bytes must be 0
u2 padding_offset = 1;
while ((bcp + padding_offset) < aligned_bcp) {
if(*(bcp + padding_offset) != 0) {
verify_error(ErrorContext::bad_code(bci),
"Nonzero padding byte in lookupswitch or tableswitch");
return;
}
padding_offset++;
}
}
int default_offset = (int) Bytes::get_Java_u4(aligned_bcp);
int keys, delta;
current_frame->pop_stack(
VerificationType::integer_type(), CHECK_VERIFY(this));
if (bcs->raw_code() == Bytecodes::_tableswitch) {
jint low = (jint)Bytes::get_Java_u4(aligned_bcp + jintSize);
jint high = (jint)Bytes::get_Java_u4(aligned_bcp + 2*jintSize);
if (low > high) {
verify_error(ErrorContext::bad_code(bci),
"low must be less than or equal to high in tableswitch");
return;
}
keys = high - low + 1;
if (keys < 0) {
verify_error(ErrorContext::bad_code(bci), "too many keys in tableswitch");
return;
}
delta = 1;
} else {
keys = (int)Bytes::get_Java_u4(aligned_bcp + jintSize);
if (keys < 0) {
verify_error(ErrorContext::bad_code(bci),
"number of keys in lookupswitch less than 0");
return;
}
delta = 2;
// Make sure that the lookupswitch items are sorted
for (int i = 0; i < (keys - 1); i++) {
jint this_key = Bytes::get_Java_u4(aligned_bcp + (2+2*i)*jintSize);
jint next_key = Bytes::get_Java_u4(aligned_bcp + (2+2*i+2)*jintSize);
if (this_key >= next_key) {
verify_error(ErrorContext::bad_code(bci),
"Bad lookupswitch instruction");
return;
}
}
}
int target = bci + default_offset;
stackmap_table->check_jump_target(current_frame, target, CHECK_VERIFY(this));
for (int i = 0; i < keys; i++) {
// Because check_jump_target() may safepoint, the bytecode could have
// moved, which means 'aligned_bcp' is no good and needs to be recalculated.
aligned_bcp = align_up(bcs->bcp() + 1, jintSize);
target = bci + (jint)Bytes::get_Java_u4(aligned_bcp+(3+i*delta)*jintSize);
stackmap_table->check_jump_target(
current_frame, target, CHECK_VERIFY(this));
}
NOT_PRODUCT(aligned_bcp = NULL); // no longer valid at this point
}
bool ClassVerifier::name_in_supers(
Symbol* ref_name, InstanceKlass* current) {
Klass* super = current->super();
while (super != NULL) {
if (super->name() == ref_name) {
return true;
}
super = super->super();
}
return false;
}
void ClassVerifier::verify_field_instructions(RawBytecodeStream* bcs,
StackMapFrame* current_frame,
const constantPoolHandle& cp,
bool allow_arrays,
TRAPS) {
u2 index = bcs->get_index_u2();
verify_cp_type(bcs->bci(), index, cp,
1 << JVM_CONSTANT_Fieldref, CHECK_VERIFY(this));
// Get field name and signature
Symbol* field_name = cp->name_ref_at(index);
Symbol* field_sig = cp->signature_ref_at(index);
// Field signature was checked in ClassFileParser.
assert(SignatureVerifier::is_valid_type_signature(field_sig),
"Invalid field signature");
// Get referenced class type
VerificationType ref_class_type = cp_ref_index_to_type(
index, cp, CHECK_VERIFY(this));
if (!ref_class_type.is_object() &&
(!allow_arrays || !ref_class_type.is_array())) {
verify_error(ErrorContext::bad_type(bcs->bci(),
TypeOrigin::cp(index, ref_class_type)),
"Expecting reference to class in class %s at constant pool index %d",
_klass->external_name(), index);
return;
}
VerificationType target_class_type = ref_class_type;
assert(sizeof(VerificationType) == sizeof(uintptr_t),
"buffer type must match VerificationType size");
uintptr_t field_type_buffer[2];
VerificationType* field_type = (VerificationType*)field_type_buffer;
// If we make a VerificationType[2] array directly, the compiler calls
// to the c-runtime library to do the allocation instead of just
// stack allocating it. Plus it would run constructors. This shows up
// in performance profiles.
SignatureStream sig_stream(field_sig, false);
VerificationType stack_object_type;
int n = change_sig_to_verificationType(&sig_stream, field_type);
u2 bci = bcs->bci();
bool is_assignable;
switch (bcs->raw_code()) {
case Bytecodes::_getstatic: {
for (int i = 0; i < n; i++) {
current_frame->push_stack(field_type[i], CHECK_VERIFY(this));
}
break;
}
case Bytecodes::_putstatic: {
for (int i = n - 1; i >= 0; i--) {
current_frame->pop_stack(field_type[i], CHECK_VERIFY(this));
}
break;
}
case Bytecodes::_getfield: {
stack_object_type = current_frame->pop_stack(
target_class_type, CHECK_VERIFY(this));
for (int i = 0; i < n; i++) {
current_frame->push_stack(field_type[i], CHECK_VERIFY(this));
}
goto check_protected;
}
case Bytecodes::_putfield: {
for (int i = n - 1; i >= 0; i--) {
current_frame->pop_stack(field_type[i], CHECK_VERIFY(this));
}
stack_object_type = current_frame->pop_stack(CHECK_VERIFY(this));
// The JVMS 2nd edition allows field initialization before the superclass
// initializer, if the field is defined within the current class.
fieldDescriptor fd;
if (stack_object_type == VerificationType::uninitialized_this_type() &&
target_class_type.equals(current_type()) &&
_klass->find_local_field(field_name, field_sig, &fd)) {
stack_object_type = current_type();
}
is_assignable = target_class_type.is_assignable_from(
stack_object_type, this, false, CHECK_VERIFY(this));
if (!is_assignable) {
verify_error(ErrorContext::bad_type(bci,
current_frame->stack_top_ctx(),
TypeOrigin::cp(index, target_class_type)),
"Bad type on operand stack in putfield");
return;
}
}
check_protected: {
if (_this_type == stack_object_type)
break; // stack_object_type must be assignable to _current_class_type
if (was_recursively_verified()) return;
Symbol* ref_class_name =
cp->klass_name_at(cp->klass_ref_index_at(index));
if (!name_in_supers(ref_class_name, current_class()))
// stack_object_type must be assignable to _current_class_type since:
// 1. stack_object_type must be assignable to ref_class.
// 2. ref_class must be _current_class or a subclass of it. It can't
// be a superclass of it. See revised JVMS 5.4.4.
break;
Klass* ref_class_oop = load_class(ref_class_name, CHECK);
if (is_protected_access(current_class(), ref_class_oop, field_name,
field_sig, false)) {
// It's protected access, check if stack object is assignable to
// current class.
is_assignable = current_type().is_assignable_from(
stack_object_type, this, true, CHECK_VERIFY(this));
if (!is_assignable) {
verify_error(ErrorContext::bad_type(bci,
current_frame->stack_top_ctx(),
TypeOrigin::implicit(current_type())),
"Bad access to protected data in getfield");
return;
}
}
break;
}
default: ShouldNotReachHere();
}
}
// Look at the method's handlers. If the bci is in the handler's try block
// then check if the handler_pc is already on the stack. If not, push it
// unless the handler has already been scanned.
void ClassVerifier::push_handlers(ExceptionTable* exhandlers,
GrowableArray<u4>* handler_list,
GrowableArray<u4>* handler_stack,
u4 bci) {
int exlength = exhandlers->length();
for(int x = 0; x < exlength; x++) {
if (bci >= exhandlers->start_pc(x) && bci < exhandlers->end_pc(x)) {
u4 exhandler_pc = exhandlers->handler_pc(x);
if (!handler_list->contains(exhandler_pc)) {
handler_stack->append_if_missing(exhandler_pc);
handler_list->append(exhandler_pc);
}
}
}
}
// Return TRUE if all code paths starting with start_bc_offset end in
// bytecode athrow or loop.
bool ClassVerifier::ends_in_athrow(u4 start_bc_offset) {
ResourceMark rm;
// Create bytecode stream.
RawBytecodeStream bcs(method());
u4 code_length = method()->code_size();
bcs.set_start(start_bc_offset);
u4 target;
// Create stack for storing bytecode start offsets for if* and *switch.
GrowableArray<u4>* bci_stack = new GrowableArray<u4>(30);
// Create stack for handlers for try blocks containing this handler.
GrowableArray<u4>* handler_stack = new GrowableArray<u4>(30);
// Create list of handlers that have been pushed onto the handler_stack
// so that handlers embedded inside of their own TRY blocks only get
// scanned once.
GrowableArray<u4>* handler_list = new GrowableArray<u4>(30);
// Create list of visited branch opcodes (goto* and if*).
GrowableArray<u4>* visited_branches = new GrowableArray<u4>(30);
ExceptionTable exhandlers(_method());
while (true) {
if (bcs.is_last_bytecode()) {
// if no more starting offsets to parse or if at the end of the
// method then return false.
if ((bci_stack->is_empty()) || ((u4)bcs.end_bci() == code_length))
return false;
// Pop a bytecode starting offset and scan from there.
bcs.set_start(bci_stack->pop());
}
Bytecodes::Code opcode = bcs.raw_next();
u4 bci = bcs.bci();
// If the bytecode is in a TRY block, push its handlers so they
// will get parsed.
push_handlers(&exhandlers, handler_list, handler_stack, bci);
switch (opcode) {
case Bytecodes::_if_icmpeq:
case Bytecodes::_if_icmpne:
case Bytecodes::_if_icmplt:
case Bytecodes::_if_icmpge:
case Bytecodes::_if_icmpgt:
case Bytecodes::_if_icmple:
case Bytecodes::_ifeq:
case Bytecodes::_ifne:
case Bytecodes::_iflt:
case Bytecodes::_ifge:
case Bytecodes::_ifgt:
case Bytecodes::_ifle:
case Bytecodes::_if_acmpeq:
case Bytecodes::_if_acmpne:
case Bytecodes::_ifnull:
case Bytecodes::_ifnonnull:
target = bcs.dest();
if (visited_branches->contains(bci)) {
if (bci_stack->is_empty()) {
if (handler_stack->is_empty()) {
return true;
} else {
// Parse the catch handlers for try blocks containing athrow.
bcs.set_start(handler_stack->pop());
}
} else {
// Pop a bytecode starting offset and scan from there.
bcs.set_start(bci_stack->pop());
}
} else {
if (target > bci) { // forward branch
if (target >= code_length) return false;
// Push the branch target onto the stack.
bci_stack->push(target);
// then, scan bytecodes starting with next.
bcs.set_start(bcs.next_bci());
} else { // backward branch
// Push bytecode offset following backward branch onto the stack.
bci_stack->push(bcs.next_bci());
// Check bytecodes starting with branch target.
bcs.set_start(target);
}
// Record target so we don't branch here again.
visited_branches->append(bci);
}
break;
case Bytecodes::_goto:
case Bytecodes::_goto_w:
target = (opcode == Bytecodes::_goto ? bcs.dest() : bcs.dest_w());
if (visited_branches->contains(bci)) {
if (bci_stack->is_empty()) {
if (handler_stack->is_empty()) {
return true;
} else {
// Parse the catch handlers for try blocks containing athrow.
bcs.set_start(handler_stack->pop());
}
} else {
// Been here before, pop new starting offset from stack.
bcs.set_start(bci_stack->pop());
}
} else {
if (target >= code_length) return false;
// Continue scanning from the target onward.
bcs.set_start(target);
// Record target so we don't branch here again.
visited_branches->append(bci);
}
break;
// Check that all switch alternatives end in 'athrow' bytecodes. Since it
// is difficult to determine where each switch alternative ends, parse
// each switch alternative until either hit a 'return', 'athrow', or reach
// the end of the method's bytecodes. This is gross but should be okay
// because:
// 1. tableswitch and lookupswitch byte codes in handlers for ctor explicit
// constructor invocations should be rare.
// 2. if each switch alternative ends in an athrow then the parsing should be
// short. If there is no athrow then it is bogus code, anyway.
case Bytecodes::_lookupswitch:
case Bytecodes::_tableswitch:
{
address aligned_bcp = align_up(bcs.bcp() + 1, jintSize);
u4 default_offset = Bytes::get_Java_u4(aligned_bcp) + bci;
int keys, delta;
if (opcode == Bytecodes::_tableswitch) {
jint low = (jint)Bytes::get_Java_u4(aligned_bcp + jintSize);
jint high = (jint)Bytes::get_Java_u4(aligned_bcp + 2*jintSize);
// This is invalid, but let the regular bytecode verifier
// report this because the user will get a better error message.
if (low > high) return true;
keys = high - low + 1;
delta = 1;
} else {
keys = (int)Bytes::get_Java_u4(aligned_bcp + jintSize);
delta = 2;
}
// Invalid, let the regular bytecode verifier deal with it.
if (keys < 0) return true;
// Push the offset of the next bytecode onto the stack.
bci_stack->push(bcs.next_bci());
// Push the switch alternatives onto the stack.
for (int i = 0; i < keys; i++) {
u4 target = bci + (jint)Bytes::get_Java_u4(aligned_bcp+(3+i*delta)*jintSize);
if (target > code_length) return false;
bci_stack->push(target);
}
// Start bytecode parsing for the switch at the default alternative.
if (default_offset > code_length) return false;
bcs.set_start(default_offset);
break;
}
case Bytecodes::_return:
return false;
case Bytecodes::_athrow:
{
if (bci_stack->is_empty()) {
if (handler_stack->is_empty()) {
return true;
} else {
// Parse the catch handlers for try blocks containing athrow.
bcs.set_start(handler_stack->pop());
}
} else {
// Pop a bytecode offset and starting scanning from there.
bcs.set_start(bci_stack->pop());
}
}
break;
default:
;
} // end switch
} // end while loop
return false;
}
void ClassVerifier::verify_invoke_init(
RawBytecodeStream* bcs, u2 ref_class_index, VerificationType ref_class_type,
StackMapFrame* current_frame, u4 code_length, bool in_try_block,
bool *this_uninit, const constantPoolHandle& cp, StackMapTable* stackmap_table,
TRAPS) {
u2 bci = bcs->bci();
VerificationType type = current_frame->pop_stack(
VerificationType::reference_check(), CHECK_VERIFY(this));
if (type == VerificationType::uninitialized_this_type()) {
// The method must be an <init> method of this class or its superclass
Klass* superk = current_class()->super();
if (ref_class_type.name() != current_class()->name() &&
ref_class_type.name() != superk->name()) {
verify_error(ErrorContext::bad_type(bci,
TypeOrigin::implicit(ref_class_type),
TypeOrigin::implicit(current_type())),
"Bad <init> method call");
return;
}
// If this invokespecial call is done from inside of a TRY block then make
// sure that all catch clause paths end in a throw. Otherwise, this can
// result in returning an incomplete object.
if (in_try_block) {
ExceptionTable exhandlers(_method());
int exlength = exhandlers.length();
for(int i = 0; i < exlength; i++) {
u2 start_pc = exhandlers.start_pc(i);
u2 end_pc = exhandlers.end_pc(i);
if (bci >= start_pc && bci < end_pc) {
if (!ends_in_athrow(exhandlers.handler_pc(i))) {
verify_error(ErrorContext::bad_code(bci),
"Bad <init> method call from after the start of a try block");
return;
} else if (log_is_enabled(Info, verification)) {
ResourceMark rm(THREAD);
log_info(verification)("Survived call to ends_in_athrow(): %s",
current_class()->name()->as_C_string());
}
}
}
// Check the exception handler target stackmaps with the locals from the
// incoming stackmap (before initialize_object() changes them to outgoing
// state).
if (was_recursively_verified()) return;
verify_exception_handler_targets(bci, true, current_frame,
stackmap_table, CHECK_VERIFY(this));
} // in_try_block
current_frame->initialize_object(type, current_type());
*this_uninit = true;
} else if (type.is_uninitialized()) {
u2 new_offset = type.bci();
address new_bcp = bcs->bcp() - bci + new_offset;
if (new_offset > (code_length - 3) || (*new_bcp) != Bytecodes::_new) {
/* Unreachable? Stack map parsing ensures valid type and new
* instructions have a valid BCI. */
verify_error(ErrorContext::bad_code(new_offset),
"Expecting new instruction");
return;
}
u2 new_class_index = Bytes::get_Java_u2(new_bcp + 1);
if (was_recursively_verified()) return;
verify_cp_class_type(bci, new_class_index, cp, CHECK_VERIFY(this));
// The method must be an <init> method of the indicated class
VerificationType new_class_type = cp_index_to_type(
new_class_index, cp, CHECK_VERIFY(this));
if (!new_class_type.equals(ref_class_type)) {
verify_error(ErrorContext::bad_type(bci,
TypeOrigin::cp(new_class_index, new_class_type),
TypeOrigin::cp(ref_class_index, ref_class_type)),
"Call to wrong <init> method");
return;
}
// According to the VM spec, if the referent class is a superclass of the
// current class, and is in a different runtime package, and the method is
// protected, then the objectref must be the current class or a subclass
// of the current class.
VerificationType objectref_type = new_class_type;
if (name_in_supers(ref_class_type.name(), current_class())) {
Klass* ref_klass = load_class(ref_class_type.name(), CHECK);
if (was_recursively_verified()) return;
Method* m = InstanceKlass::cast(ref_klass)->uncached_lookup_method(
vmSymbols::object_initializer_name(),
cp->signature_ref_at(bcs->get_index_u2()),
Klass::find_overpass);
// Do nothing if method is not found. Let resolution detect the error.
if (m != NULL) {
InstanceKlass* mh = m->method_holder();
if (m->is_protected() && !mh->is_same_class_package(_klass)) {
bool assignable = current_type().is_assignable_from(
objectref_type, this, true, CHECK_VERIFY(this));
if (!assignable) {
verify_error(ErrorContext::bad_type(bci,
TypeOrigin::cp(new_class_index, objectref_type),
TypeOrigin::implicit(current_type())),
"Bad access to protected <init> method");
return;
}
}
}
}
// Check the exception handler target stackmaps with the locals from the
// incoming stackmap (before initialize_object() changes them to outgoing
// state).
if (in_try_block) {
if (was_recursively_verified()) return;
verify_exception_handler_targets(bci, *this_uninit, current_frame,
stackmap_table, CHECK_VERIFY(this));
}
current_frame->initialize_object(type, new_class_type);
} else {
verify_error(ErrorContext::bad_type(bci, current_frame->stack_top_ctx()),
"Bad operand type when invoking <init>");
return;
}
}
bool ClassVerifier::is_same_or_direct_interface(
InstanceKlass* klass,
VerificationType klass_type,
VerificationType ref_class_type) {
if (ref_class_type.equals(klass_type)) return true;
Array<InstanceKlass*>* local_interfaces = klass->local_interfaces();
if (local_interfaces != NULL) {
for (int x = 0; x < local_interfaces->length(); x++) {
InstanceKlass* k = local_interfaces->at(x);
assert (k != NULL && k->is_interface(), "invalid interface");
if (ref_class_type.equals(VerificationType::reference_type(k->name()))) {
return true;
}
}
}
return false;
}
void ClassVerifier::verify_invoke_instructions(
RawBytecodeStream* bcs, u4 code_length, StackMapFrame* current_frame,
bool in_try_block, bool *this_uninit, VerificationType return_type,
const constantPoolHandle& cp, StackMapTable* stackmap_table, TRAPS) {
// Make sure the constant pool item is the right type
u2 index = bcs->get_index_u2();
Bytecodes::Code opcode = bcs->raw_code();
unsigned int types = 0;
switch (opcode) {
case Bytecodes::_invokeinterface:
types = 1 << JVM_CONSTANT_InterfaceMethodref;
break;
case Bytecodes::_invokedynamic:
types = 1 << JVM_CONSTANT_InvokeDynamic;
break;
case Bytecodes::_invokespecial:
case Bytecodes::_invokestatic:
types = (_klass->major_version() < STATIC_METHOD_IN_INTERFACE_MAJOR_VERSION) ?
(1 << JVM_CONSTANT_Methodref) :
((1 << JVM_CONSTANT_InterfaceMethodref) | (1 << JVM_CONSTANT_Methodref));
break;
default:
types = 1 << JVM_CONSTANT_Methodref;
}
verify_cp_type(bcs->bci(), index, cp, types, CHECK_VERIFY(this));
// Get method name and signature
Symbol* method_name = cp->name_ref_at(index);
Symbol* method_sig = cp->signature_ref_at(index);
// Method signature was checked in ClassFileParser.
assert(SignatureVerifier::is_valid_method_signature(method_sig),
"Invalid method signature");
// Get referenced class type
VerificationType ref_class_type;
if (opcode == Bytecodes::_invokedynamic) {
if (_klass->major_version() < Verifier::INVOKEDYNAMIC_MAJOR_VERSION) {
class_format_error(
"invokedynamic instructions not supported by this class file version (%d), class %s",
_klass->major_version(), _klass->external_name());
return;
}
} else {
ref_class_type = cp_ref_index_to_type(index, cp, CHECK_VERIFY(this));
}
assert(sizeof(VerificationType) == sizeof(uintptr_t),
"buffer type must match VerificationType size");
// Get the UTF8 index for this signature.
int sig_index = cp->signature_ref_index_at(cp->name_and_type_ref_index_at(index));
// Get the signature's verification types.
sig_as_verification_types* mth_sig_verif_types;
sig_as_verification_types** mth_sig_verif_types_ptr = method_signatures_table()->get(sig_index);
if (mth_sig_verif_types_ptr != NULL) {
// Found the entry for the signature's verification types in the hash table.
mth_sig_verif_types = *mth_sig_verif_types_ptr;
assert(mth_sig_verif_types != NULL, "Unexpected NULL sig_as_verification_types value");
} else {
// Not found, add the entry to the table.
GrowableArray<VerificationType>* verif_types = new GrowableArray<VerificationType>(10);
mth_sig_verif_types = new sig_as_verification_types(verif_types);
create_method_sig_entry(mth_sig_verif_types, sig_index, CHECK_VERIFY(this));
}
// Get the number of arguments for this signature.
int nargs = mth_sig_verif_types->num_args();
// Check instruction operands
u2 bci = bcs->bci();
if (opcode == Bytecodes::_invokeinterface) {
address bcp = bcs->bcp();
// 4905268: count operand in invokeinterface should be nargs+1, not nargs.
// JSR202 spec: The count operand of an invokeinterface instruction is valid if it is
// the difference between the size of the operand stack before and after the instruction
// executes.
if (*(bcp+3) != (nargs+1)) {
verify_error(ErrorContext::bad_code(bci),
"Inconsistent args count operand in invokeinterface");
return;
}
if (*(bcp+4) != 0) {
verify_error(ErrorContext::bad_code(bci),
"Fourth operand byte of invokeinterface must be zero");
return;
}
}
if (opcode == Bytecodes::_invokedynamic) {
address bcp = bcs->bcp();
if (*(bcp+3) != 0 || *(bcp+4) != 0) {
verify_error(ErrorContext::bad_code(bci),
"Third and fourth operand bytes of invokedynamic must be zero");
return;
}
}
if (method_name->char_at(0) == JVM_SIGNATURE_SPECIAL) {
// Make sure <init> can only be invoked by invokespecial
if (opcode != Bytecodes::_invokespecial ||
method_name != vmSymbols::object_initializer_name()) {
verify_error(ErrorContext::bad_code(bci),
"Illegal call to internal method");
return;
}
} else if (opcode == Bytecodes::_invokespecial
&& !is_same_or_direct_interface(current_class(), current_type(), ref_class_type)
&& !ref_class_type.equals(VerificationType::reference_type(
current_class()->super()->name()))) {
bool subtype = false;
bool have_imr_indirect = cp->tag_at(index).value() == JVM_CONSTANT_InterfaceMethodref;
if (!current_class()->is_unsafe_anonymous()) {
subtype = ref_class_type.is_assignable_from(
current_type(), this, false, CHECK_VERIFY(this));
} else {
VerificationType unsafe_anonymous_host_type =
VerificationType::reference_type(current_class()->unsafe_anonymous_host()->name());
subtype = ref_class_type.is_assignable_from(unsafe_anonymous_host_type, this, false, CHECK_VERIFY(this));
// If invokespecial of IMR, need to recheck for same or
// direct interface relative to the host class
have_imr_indirect = (have_imr_indirect &&
!is_same_or_direct_interface(
current_class()->unsafe_anonymous_host(),
unsafe_anonymous_host_type, ref_class_type));
}
if (!subtype) {
verify_error(ErrorContext::bad_code(bci),
"Bad invokespecial instruction: "
"current class isn't assignable to reference class.");
return;
} else if (have_imr_indirect) {
verify_error(ErrorContext::bad_code(bci),
"Bad invokespecial instruction: "
"interface method reference is in an indirect superinterface.");
return;
}
}
// Get the verification types for the method's arguments.
GrowableArray<VerificationType>* sig_verif_types = mth_sig_verif_types->sig_verif_types();
assert(sig_verif_types != NULL, "Missing signature's array of verification types");
// Match method descriptor with operand stack
// The arguments are on the stack in descending order.
for (int i = nargs - 1; i >= 0; i--) { // Run backwards
current_frame->pop_stack(sig_verif_types->at(i), CHECK_VERIFY(this));
}
// Check objectref on operand stack
if (opcode != Bytecodes::_invokestatic &&
opcode != Bytecodes::_invokedynamic) {
if (method_name == vmSymbols::object_initializer_name()) { // <init> method
verify_invoke_init(bcs, index, ref_class_type, current_frame,
code_length, in_try_block, this_uninit, cp, stackmap_table,
CHECK_VERIFY(this));
if (was_recursively_verified()) return;
} else { // other methods
// Ensures that target class is assignable to method class.
if (opcode == Bytecodes::_invokespecial) {
if (!current_class()->is_unsafe_anonymous()) {
current_frame->pop_stack(current_type(), CHECK_VERIFY(this));
} else {
// anonymous class invokespecial calls: check if the
// objectref is a subtype of the unsafe_anonymous_host of the current class
// to allow an anonymous class to reference methods in the unsafe_anonymous_host
VerificationType top = current_frame->pop_stack(CHECK_VERIFY(this));
VerificationType hosttype =
VerificationType::reference_type(current_class()->unsafe_anonymous_host()->name());
bool subtype = hosttype.is_assignable_from(top, this, false, CHECK_VERIFY(this));
if (!subtype) {
verify_error( ErrorContext::bad_type(current_frame->offset(),
current_frame->stack_top_ctx(),
TypeOrigin::implicit(top)),
"Bad type on operand stack");
return;
}
}
} else if (opcode == Bytecodes::_invokevirtual) {
VerificationType stack_object_type =
current_frame->pop_stack(ref_class_type, CHECK_VERIFY(this));
if (current_type() != stack_object_type) {
if (was_recursively_verified()) return;
assert(cp->cache() == NULL, "not rewritten yet");
Symbol* ref_class_name =
cp->klass_name_at(cp->klass_ref_index_at(index));
// See the comments in verify_field_instructions() for
// the rationale behind this.
if (name_in_supers(ref_class_name, current_class())) {
Klass* ref_class = load_class(ref_class_name, CHECK);
if (is_protected_access(
_klass, ref_class, method_name, method_sig, true)) {
// It's protected access, check if stack object is
// assignable to current class.
bool is_assignable = current_type().is_assignable_from(
stack_object_type, this, true, CHECK_VERIFY(this));
if (!is_assignable) {
if (ref_class_type.name() == vmSymbols::java_lang_Object()
&& stack_object_type.is_array()
&& method_name == vmSymbols::clone_name()) {
// Special case: arrays pretend to implement public Object
// clone().
} else {
verify_error(ErrorContext::bad_type(bci,
current_frame->stack_top_ctx(),
TypeOrigin::implicit(current_type())),
"Bad access to protected data in invokevirtual");
return;
}
}
}
}
}
} else {
assert(opcode == Bytecodes::_invokeinterface, "Unexpected opcode encountered");
current_frame->pop_stack(ref_class_type, CHECK_VERIFY(this));
}
}
}
// Push the result type.
int sig_verif_types_len = sig_verif_types->length();
if (sig_verif_types_len > nargs) { // There's a return type
if (method_name == vmSymbols::object_initializer_name()) {
// <init> method must have a void return type
/* Unreachable? Class file parser verifies that methods with '<' have
* void return */
verify_error(ErrorContext::bad_code(bci),
"Return type must be void in <init> method");
return;
}
assert(sig_verif_types_len <= nargs + 2,
"Signature verification types array return type is bogus");
for (int i = nargs; i < sig_verif_types_len; i++) {
assert(i == nargs || sig_verif_types->at(i).is_long2() ||
sig_verif_types->at(i).is_double2(), "Unexpected return verificationType");
current_frame->push_stack(sig_verif_types->at(i), CHECK_VERIFY(this));
}
}
}
VerificationType ClassVerifier::get_newarray_type(
u2 index, u2 bci, TRAPS) {
const char* from_bt[] = {
NULL, NULL, NULL, NULL, "[Z", "[C", "[F", "[D", "[B", "[S", "[I", "[J",
};
if (index < T_BOOLEAN || index > T_LONG) {
verify_error(ErrorContext::bad_code(bci), "Illegal newarray instruction");
return VerificationType::bogus_type();
}
// from_bt[index] contains the array signature which has a length of 2
Symbol* sig = create_temporary_symbol(from_bt[index], 2);
return VerificationType::reference_type(sig);
}
void ClassVerifier::verify_anewarray(
u2 bci, u2 index, const constantPoolHandle& cp,
StackMapFrame* current_frame, TRAPS) {
verify_cp_class_type(bci, index, cp, CHECK_VERIFY(this));
current_frame->pop_stack(
VerificationType::integer_type(), CHECK_VERIFY(this));
if (was_recursively_verified()) return;
VerificationType component_type =
cp_index_to_type(index, cp, CHECK_VERIFY(this));
int length;
char* arr_sig_str;
if (component_type.is_array()) { // it's an array
const char* component_name = component_type.name()->as_utf8();
// Check for more than MAX_ARRAY_DIMENSIONS
length = (int)strlen(component_name);
if (length > MAX_ARRAY_DIMENSIONS &&
component_name[MAX_ARRAY_DIMENSIONS - 1] == JVM_SIGNATURE_ARRAY) {
verify_error(ErrorContext::bad_code(bci),
"Illegal anewarray instruction, array has more than 255 dimensions");
}
// add one dimension to component
length++;
arr_sig_str = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, length + 1);
int n = os::snprintf(arr_sig_str, length + 1, "%c%s",
JVM_SIGNATURE_ARRAY, component_name);
assert(n == length, "Unexpected number of characters in string");
} else { // it's an object or interface
const char* component_name = component_type.name()->as_utf8();
// add one dimension to component with 'L' prepended and ';' postpended.
length = (int)strlen(component_name) + 3;
arr_sig_str = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, length + 1);
int n = os::snprintf(arr_sig_str, length + 1, "%c%c%s;",
JVM_SIGNATURE_ARRAY, JVM_SIGNATURE_CLASS, component_name);
assert(n == length, "Unexpected number of characters in string");
}
Symbol* arr_sig = create_temporary_symbol(arr_sig_str, length);
VerificationType new_array_type = VerificationType::reference_type(arr_sig);
current_frame->push_stack(new_array_type, CHECK_VERIFY(this));
}
void ClassVerifier::verify_iload(u2 index, StackMapFrame* current_frame, TRAPS) {
current_frame->get_local(
index, VerificationType::integer_type(), CHECK_VERIFY(this));
current_frame->push_stack(
VerificationType::integer_type(), CHECK_VERIFY(this));
}
void ClassVerifier::verify_lload(u2 index, StackMapFrame* current_frame, TRAPS) {
current_frame->get_local_2(
index, VerificationType::long_type(),
VerificationType::long2_type(), CHECK_VERIFY(this));
current_frame->push_stack_2(
VerificationType::long_type(),
VerificationType::long2_type(), CHECK_VERIFY(this));
}
void ClassVerifier::verify_fload(u2 index, StackMapFrame* current_frame, TRAPS) {
current_frame->get_local(
index, VerificationType::float_type(), CHECK_VERIFY(this));
current_frame->push_stack(
VerificationType::float_type(), CHECK_VERIFY(this));
}
void ClassVerifier::verify_dload(u2 index, StackMapFrame* current_frame, TRAPS) {
current_frame->get_local_2(
index, VerificationType::double_type(),
VerificationType::double2_type(), CHECK_VERIFY(this));
current_frame->push_stack_2(
VerificationType::double_type(),
VerificationType::double2_type(), CHECK_VERIFY(this));
}
void ClassVerifier::verify_aload(u2 index, StackMapFrame* current_frame, TRAPS) {
VerificationType type = current_frame->get_local(
index, VerificationType::reference_check(), CHECK_VERIFY(this));
current_frame->push_stack(type, CHECK_VERIFY(this));
}
void ClassVerifier::verify_istore(u2 index, StackMapFrame* current_frame, TRAPS) {
current_frame->pop_stack(
VerificationType::integer_type(), CHECK_VERIFY(this));
current_frame->set_local(
index, VerificationType::integer_type(), CHECK_VERIFY(this));
}
void ClassVerifier::verify_lstore(u2 index, StackMapFrame* current_frame, TRAPS) {
current_frame->pop_stack_2(
VerificationType::long2_type(),
VerificationType::long_type(), CHECK_VERIFY(this));
current_frame->set_local_2(
index, VerificationType::long_type(),
VerificationType::long2_type(), CHECK_VERIFY(this));
}
void ClassVerifier::verify_fstore(u2 index, StackMapFrame* current_frame, TRAPS) {
current_frame->pop_stack(VerificationType::float_type(), CHECK_VERIFY(this));
current_frame->set_local(
index, VerificationType::float_type(), CHECK_VERIFY(this));
}
void ClassVerifier::verify_dstore(u2 index, StackMapFrame* current_frame, TRAPS) {
current_frame->pop_stack_2(
VerificationType::double2_type(),
VerificationType::double_type(), CHECK_VERIFY(this));
current_frame->set_local_2(
index, VerificationType::double_type(),
VerificationType::double2_type(), CHECK_VERIFY(this));
}
void ClassVerifier::verify_astore(u2 index, StackMapFrame* current_frame, TRAPS) {
VerificationType type = current_frame->pop_stack(
VerificationType::reference_check(), CHECK_VERIFY(this));
current_frame->set_local(index, type, CHECK_VERIFY(this));
}
void ClassVerifier::verify_iinc(u2 index, StackMapFrame* current_frame, TRAPS) {
VerificationType type = current_frame->get_local(
index, VerificationType::integer_type(), CHECK_VERIFY(this));
current_frame->set_local(index, type, CHECK_VERIFY(this));
}
void ClassVerifier::verify_return_value(
VerificationType return_type, VerificationType type, u2 bci,
StackMapFrame* current_frame, TRAPS) {
if (return_type == VerificationType::bogus_type()) {
verify_error(ErrorContext::bad_type(bci,
current_frame->stack_top_ctx(), TypeOrigin::signature(return_type)),
"Method expects a return value");
return;
}
bool match = return_type.is_assignable_from(type, this, false, CHECK_VERIFY(this));
if (!match) {
verify_error(ErrorContext::bad_type(bci,
current_frame->stack_top_ctx(), TypeOrigin::signature(return_type)),
"Bad return type");
return;
}
}
// The verifier creates symbols which are substrings of Symbols.
// These are stored in the verifier until the end of verification so that
// they can be reference counted.
Symbol* ClassVerifier::create_temporary_symbol(const Symbol *s, int begin,
int end) {
const char* name = (const char*)s->base() + begin;
int length = end - begin;
return create_temporary_symbol(name, length);
}
Symbol* ClassVerifier::create_temporary_symbol(const char *name, int length) {
// Quick deduplication check
if (_previous_symbol != NULL && _previous_symbol->equals(name, length)) {
return _previous_symbol;
}
Symbol* sym = SymbolTable::new_symbol(name, length);
if (!sym->is_permanent()) {
if (_symbols == NULL) {
_symbols = new GrowableArray<Symbol*>(50, 0, NULL);
}
_symbols->push(sym);
}
_previous_symbol = sym;
return sym;
}