src/share/vm/ci/ciField.cpp

Fri, 18 Jul 2014 09:04:01 +0200

author
goetz
date
Fri, 18 Jul 2014 09:04:01 +0200
changeset 6812
00cf2b6f51b9
parent 5732
b2e698d2276c
child 6876
710a3c8b516e
child 8176
714096aec397
permissions
-rw-r--r--

8050978: Fix bad field access check in C1 and C2
Summary: JCK8 test vm/constantpool/accessControl/accessControl004/accessControl00402m3/accessControl00402m3.html fails with -Xbatch -Xcomp due to bad field access check in C1 and C2. Fix: In ciField::ciField(), just before the canonical holder is stored into the _holder variable (and which is used by ciField::will_link()) perform an additional access check with the holder declared in the class file. If this check fails, store the declared holder instead and ciField::will_link() will bail out compilation for this field later on. Then, the interpreter will throw an PrivilegedAccessException at runtime.
Reviewed-by: kvn, vlivanov
Contributed-by: andreas.schoesser@sap.com

duke@435 1 /*
drchase@5732 2 * Copyright (c) 1999, 2013, Oracle and/or its affiliates. All rights reserved.
duke@435 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
duke@435 4 *
duke@435 5 * This code is free software; you can redistribute it and/or modify it
duke@435 6 * under the terms of the GNU General Public License version 2 only, as
duke@435 7 * published by the Free Software Foundation.
duke@435 8 *
duke@435 9 * This code is distributed in the hope that it will be useful, but WITHOUT
duke@435 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
duke@435 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
duke@435 12 * version 2 for more details (a copy is included in the LICENSE file that
duke@435 13 * accompanied this code).
duke@435 14 *
duke@435 15 * You should have received a copy of the GNU General Public License version
duke@435 16 * 2 along with this work; if not, write to the Free Software Foundation,
duke@435 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
duke@435 18 *
trims@1907 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
trims@1907 20 * or visit www.oracle.com if you need additional information or have any
trims@1907 21 * questions.
duke@435 22 *
duke@435 23 */
duke@435 24
stefank@2314 25 #include "precompiled.hpp"
stefank@2314 26 #include "ci/ciField.hpp"
stefank@2314 27 #include "ci/ciInstanceKlass.hpp"
stefank@2314 28 #include "ci/ciUtilities.hpp"
stefank@2314 29 #include "classfile/systemDictionary.hpp"
stefank@2314 30 #include "gc_interface/collectedHeap.inline.hpp"
stefank@2314 31 #include "interpreter/linkResolver.hpp"
stefank@2314 32 #include "memory/universe.inline.hpp"
stefank@2314 33 #include "oops/oop.inline.hpp"
stefank@2314 34 #include "oops/oop.inline2.hpp"
stefank@2314 35 #include "runtime/fieldDescriptor.hpp"
duke@435 36
duke@435 37 // ciField
duke@435 38 //
duke@435 39 // This class represents the result of a field lookup in the VM.
duke@435 40 // The lookup may not succeed, in which case the information in
duke@435 41 // the ciField will be incomplete.
duke@435 42
duke@435 43 // The ciObjectFactory cannot create circular data structures in one query.
duke@435 44 // To avoid vicious circularities, we initialize ciField::_type to NULL
duke@435 45 // for reference types and derive it lazily from the ciField::_signature.
duke@435 46 // Primitive types are eagerly initialized, and basic layout queries
duke@435 47 // can succeed without initialization, using only the BasicType of the field.
duke@435 48
duke@435 49 // Notes on bootstrapping and shared CI objects: A field is shared if and
duke@435 50 // only if it is (a) non-static and (b) declared by a shared instance klass.
duke@435 51 // This allows non-static field lists to be cached on shared types.
duke@435 52 // Because the _type field is lazily initialized, however, there is a
duke@435 53 // special restriction that a shared field cannot cache an unshared type.
duke@435 54 // This puts a small performance penalty on shared fields with unshared
duke@435 55 // types, such as StackTraceElement[] Throwable.stackTrace.
duke@435 56 // (Throwable is shared because ClassCastException is shared, but
duke@435 57 // StackTraceElement is not presently shared.)
duke@435 58
duke@435 59 // It is not a vicious circularity for a ciField to recursively create
duke@435 60 // the ciSymbols necessary to represent its name and signature.
duke@435 61 // Therefore, these items are created eagerly, and the name and signature
duke@435 62 // of a shared field are themselves shared symbols. This somewhat
duke@435 63 // pollutes the set of shared CI objects: It grows from 50 to 93 items,
duke@435 64 // with all of the additional 43 being uninteresting shared ciSymbols.
duke@435 65 // This adds at most one step to the binary search, an amount which
duke@435 66 // decreases for complex compilation tasks.
duke@435 67
duke@435 68 // ------------------------------------------------------------------
duke@435 69 // ciField::ciField
never@3854 70 ciField::ciField(ciInstanceKlass* klass, int index): _known_to_link_with_put(NULL), _known_to_link_with_get(NULL) {
duke@435 71 ASSERT_IN_VM;
duke@435 72 CompilerThread *thread = CompilerThread::current();
duke@435 73
duke@435 74 assert(ciObjectFactory::is_initialized(), "not a shared field");
duke@435 75
duke@435 76 assert(klass->get_instanceKlass()->is_linked(), "must be linked before using its constan-pool");
duke@435 77
duke@435 78 constantPoolHandle cpool(thread, klass->get_instanceKlass()->constants());
duke@435 79
duke@435 80 // Get the field's name, signature, and type.
coleenp@2497 81 Symbol* name = cpool->name_ref_at(index);
coleenp@2497 82 _name = ciEnv::current(thread)->get_symbol(name);
duke@435 83
duke@435 84 int nt_index = cpool->name_and_type_ref_index_at(index);
duke@435 85 int sig_index = cpool->signature_ref_index_at(nt_index);
coleenp@2497 86 Symbol* signature = cpool->symbol_at(sig_index);
coleenp@2497 87 _signature = ciEnv::current(thread)->get_symbol(signature);
duke@435 88
coleenp@2497 89 BasicType field_type = FieldType::basic_type(signature);
duke@435 90
duke@435 91 // If the field is a pointer type, get the klass of the
duke@435 92 // field.
duke@435 93 if (field_type == T_OBJECT || field_type == T_ARRAY) {
duke@435 94 bool ignore;
duke@435 95 // This is not really a class reference; the index always refers to the
duke@435 96 // field's type signature, as a symbol. Linkage checks do not apply.
twisti@1573 97 _type = ciEnv::current(thread)->get_klass_by_index(cpool, sig_index, ignore, klass);
duke@435 98 } else {
duke@435 99 _type = ciType::make(field_type);
duke@435 100 }
duke@435 101
coleenp@2497 102 _name = (ciSymbol*)ciEnv::current(thread)->get_symbol(name);
duke@435 103
duke@435 104 // Get the field's declared holder.
duke@435 105 //
duke@435 106 // Note: we actually create a ciInstanceKlass for this klass,
duke@435 107 // even though we may not need to.
duke@435 108 int holder_index = cpool->klass_ref_index_at(index);
duke@435 109 bool holder_is_accessible;
duke@435 110 ciInstanceKlass* declared_holder =
twisti@1573 111 ciEnv::current(thread)->get_klass_by_index(cpool, holder_index,
twisti@1573 112 holder_is_accessible,
twisti@1573 113 klass)->as_instance_klass();
duke@435 114
duke@435 115 // The declared holder of this field may not have been loaded.
duke@435 116 // Bail out with partial field information.
duke@435 117 if (!holder_is_accessible) {
drchase@5732 118 // _type has already been set.
duke@435 119 // The default values for _flags and _constant_value will suffice.
duke@435 120 // We need values for _holder, _offset, and _is_constant,
duke@435 121 _holder = declared_holder;
duke@435 122 _offset = -1;
duke@435 123 _is_constant = false;
duke@435 124 return;
duke@435 125 }
duke@435 126
coleenp@4037 127 InstanceKlass* loaded_decl_holder = declared_holder->get_instanceKlass();
duke@435 128
duke@435 129 // Perform the field lookup.
duke@435 130 fieldDescriptor field_desc;
coleenp@4037 131 Klass* canonical_holder =
coleenp@2497 132 loaded_decl_holder->find_field(name, signature, &field_desc);
duke@435 133 if (canonical_holder == NULL) {
duke@435 134 // Field lookup failed. Will be detected by will_link.
duke@435 135 _holder = declared_holder;
duke@435 136 _offset = -1;
duke@435 137 _is_constant = false;
duke@435 138 return;
duke@435 139 }
duke@435 140
goetz@6812 141 // Access check based on declared_holder. canonical_holder should not be used
goetz@6812 142 // to check access because it can erroneously succeed. If this check fails,
goetz@6812 143 // propagate the declared holder to will_link() which in turn will bail out
goetz@6812 144 // compilation for this field access.
goetz@6812 145 if (!Reflection::verify_field_access(klass->get_Klass(), declared_holder->get_Klass(), canonical_holder, field_desc.access_flags(), true)) {
goetz@6812 146 _holder = declared_holder;
goetz@6812 147 _offset = -1;
goetz@6812 148 _is_constant = false;
goetz@6812 149 return;
goetz@6812 150 }
goetz@6812 151
duke@435 152 assert(canonical_holder == field_desc.field_holder(), "just checking");
duke@435 153 initialize_from(&field_desc);
duke@435 154 }
duke@435 155
never@3854 156 ciField::ciField(fieldDescriptor *fd): _known_to_link_with_put(NULL), _known_to_link_with_get(NULL) {
duke@435 157 ASSERT_IN_VM;
duke@435 158
duke@435 159 // Get the field's name, signature, and type.
duke@435 160 ciEnv* env = CURRENT_ENV;
coleenp@2497 161 _name = env->get_symbol(fd->name());
coleenp@2497 162 _signature = env->get_symbol(fd->signature());
duke@435 163
duke@435 164 BasicType field_type = fd->field_type();
duke@435 165
duke@435 166 // If the field is a pointer type, get the klass of the
duke@435 167 // field.
duke@435 168 if (field_type == T_OBJECT || field_type == T_ARRAY) {
duke@435 169 _type = NULL; // must call compute_type on first access
duke@435 170 } else {
duke@435 171 _type = ciType::make(field_type);
duke@435 172 }
duke@435 173
duke@435 174 initialize_from(fd);
duke@435 175
duke@435 176 // Either (a) it is marked shared, or else (b) we are done bootstrapping.
duke@435 177 assert(is_shared() || ciObjectFactory::is_initialized(),
duke@435 178 "bootstrap classes must not create & cache unshared fields");
duke@435 179 }
duke@435 180
jrose@1608 181 static bool trust_final_non_static_fields(ciInstanceKlass* holder) {
jrose@1608 182 if (holder == NULL)
jrose@1608 183 return false;
jrose@1608 184 if (holder->name() == ciSymbol::java_lang_System())
jrose@1608 185 // Never trust strangely unstable finals: System.out, etc.
jrose@1608 186 return false;
jrose@1608 187 // Even if general trusting is disabled, trust system-built closures in these packages.
jrose@2639 188 if (holder->is_in_package("java/lang/invoke") || holder->is_in_package("sun/invoke"))
jrose@1608 189 return true;
jrose@1608 190 return TrustFinalNonStaticFields;
jrose@1608 191 }
jrose@1608 192
duke@435 193 void ciField::initialize_from(fieldDescriptor* fd) {
duke@435 194 // Get the flags, offset, and canonical holder of the field.
duke@435 195 _flags = ciFlags(fd->access_flags());
duke@435 196 _offset = fd->offset();
coleenp@4037 197 _holder = CURRENT_ENV->get_instance_klass(fd->field_holder());
duke@435 198
duke@435 199 // Check to see if the field is constant.
vlivanov@5658 200 bool is_final = this->is_final();
vlivanov@5658 201 bool is_stable = FoldStableValues && this->is_stable();
vlivanov@5658 202 if (_holder->is_initialized() && (is_final || is_stable)) {
twisti@1573 203 if (!this->is_static()) {
jrose@2639 204 // A field can be constant if it's a final static field or if
jrose@2639 205 // it's a final non-static field of a trusted class (classes in
jrose@2639 206 // java.lang.invoke and sun.invoke packages and subpackages).
vlivanov@5658 207 if (is_stable || trust_final_non_static_fields(_holder)) {
twisti@1573 208 _is_constant = true;
twisti@1573 209 return;
twisti@1573 210 }
twisti@1573 211 _is_constant = false;
twisti@1573 212 return;
twisti@1573 213 }
twisti@1573 214
duke@435 215 // This field just may be constant. The only cases where it will
duke@435 216 // not be constant are:
duke@435 217 //
duke@435 218 // 1. The field holds a non-perm-space oop. The field is, strictly
duke@435 219 // speaking, constant but we cannot embed non-perm-space oops into
duke@435 220 // generated code. For the time being we need to consider the
duke@435 221 // field to be not constant.
duke@435 222 // 2. The field is a *special* static&final field whose value
duke@435 223 // may change. The three examples are java.lang.System.in,
duke@435 224 // java.lang.System.out, and java.lang.System.err.
duke@435 225
coleenp@4037 226 KlassHandle k = _holder->get_Klass();
never@1577 227 assert( SystemDictionary::System_klass() != NULL, "Check once per vm");
never@2568 228 if( k() == SystemDictionary::System_klass() ) {
duke@435 229 // Check offsets for case 2: System.in, System.out, or System.err
duke@435 230 if( _offset == java_lang_System::in_offset_in_bytes() ||
duke@435 231 _offset == java_lang_System::out_offset_in_bytes() ||
duke@435 232 _offset == java_lang_System::err_offset_in_bytes() ) {
duke@435 233 _is_constant = false;
duke@435 234 return;
duke@435 235 }
duke@435 236 }
duke@435 237
never@2658 238 Handle mirror = k->java_mirror();
never@2658 239
duke@435 240 switch(type()->basic_type()) {
duke@435 241 case T_BYTE:
never@2658 242 _constant_value = ciConstant(type()->basic_type(), mirror->byte_field(_offset));
duke@435 243 break;
duke@435 244 case T_CHAR:
never@2658 245 _constant_value = ciConstant(type()->basic_type(), mirror->char_field(_offset));
duke@435 246 break;
duke@435 247 case T_SHORT:
never@2658 248 _constant_value = ciConstant(type()->basic_type(), mirror->short_field(_offset));
duke@435 249 break;
duke@435 250 case T_BOOLEAN:
never@2658 251 _constant_value = ciConstant(type()->basic_type(), mirror->bool_field(_offset));
duke@435 252 break;
duke@435 253 case T_INT:
never@2658 254 _constant_value = ciConstant(type()->basic_type(), mirror->int_field(_offset));
duke@435 255 break;
duke@435 256 case T_FLOAT:
never@2658 257 _constant_value = ciConstant(mirror->float_field(_offset));
duke@435 258 break;
duke@435 259 case T_DOUBLE:
never@2658 260 _constant_value = ciConstant(mirror->double_field(_offset));
duke@435 261 break;
duke@435 262 case T_LONG:
never@2658 263 _constant_value = ciConstant(mirror->long_field(_offset));
duke@435 264 break;
duke@435 265 case T_OBJECT:
duke@435 266 case T_ARRAY:
duke@435 267 {
never@2658 268 oop o = mirror->obj_field(_offset);
duke@435 269
duke@435 270 // A field will be "constant" if it is known always to be
duke@435 271 // a non-null reference to an instance of a particular class,
duke@435 272 // or to a particular array. This can happen even if the instance
duke@435 273 // or array is not perm. In such a case, an "unloaded" ciArray
duke@435 274 // or ciInstance is created. The compiler may be able to use
duke@435 275 // information about the object's class (which is exact) or length.
duke@435 276
duke@435 277 if (o == NULL) {
duke@435 278 _constant_value = ciConstant(type()->basic_type(), ciNullObject::make());
duke@435 279 } else {
duke@435 280 _constant_value = ciConstant(type()->basic_type(), CURRENT_ENV->get_object(o));
duke@435 281 assert(_constant_value.as_object() == CURRENT_ENV->get_object(o), "check interning");
duke@435 282 }
duke@435 283 }
duke@435 284 }
vlivanov@5658 285 if (is_stable && _constant_value.is_null_or_zero()) {
vlivanov@5658 286 // It is not a constant after all; treat it as uninitialized.
vlivanov@5658 287 _is_constant = false;
vlivanov@5658 288 } else {
vlivanov@5658 289 _is_constant = true;
vlivanov@5658 290 }
duke@435 291 } else {
duke@435 292 _is_constant = false;
duke@435 293 }
duke@435 294 }
duke@435 295
duke@435 296 // ------------------------------------------------------------------
duke@435 297 // ciField::compute_type
duke@435 298 //
duke@435 299 // Lazily compute the type, if it is an instance klass.
duke@435 300 ciType* ciField::compute_type() {
duke@435 301 GUARDED_VM_ENTRY(return compute_type_impl();)
duke@435 302 }
duke@435 303
duke@435 304 ciType* ciField::compute_type_impl() {
jrose@2982 305 ciKlass* type = CURRENT_ENV->get_klass_by_name_impl(_holder, constantPoolHandle(), _signature, false);
duke@435 306 if (!type->is_primitive_type() && is_shared()) {
duke@435 307 // We must not cache a pointer to an unshared type, in a shared field.
duke@435 308 bool type_is_also_shared = false;
duke@435 309 if (type->is_type_array_klass()) {
duke@435 310 type_is_also_shared = true; // int[] etc. are explicitly bootstrapped
duke@435 311 } else if (type->is_instance_klass()) {
duke@435 312 type_is_also_shared = type->as_instance_klass()->is_shared();
duke@435 313 } else {
duke@435 314 // Currently there is no 'shared' query for array types.
duke@435 315 type_is_also_shared = !ciObjectFactory::is_initialized();
duke@435 316 }
duke@435 317 if (!type_is_also_shared)
duke@435 318 return type; // Bummer.
duke@435 319 }
duke@435 320 _type = type;
duke@435 321 return type;
duke@435 322 }
duke@435 323
duke@435 324
duke@435 325 // ------------------------------------------------------------------
duke@435 326 // ciField::will_link
duke@435 327 //
duke@435 328 // Can a specific access to this field be made without causing
duke@435 329 // link errors?
duke@435 330 bool ciField::will_link(ciInstanceKlass* accessing_klass,
duke@435 331 Bytecodes::Code bc) {
duke@435 332 VM_ENTRY_MARK;
never@3854 333 assert(bc == Bytecodes::_getstatic || bc == Bytecodes::_putstatic ||
never@3854 334 bc == Bytecodes::_getfield || bc == Bytecodes::_putfield,
never@3854 335 "unexpected bytecode");
never@3854 336
duke@435 337 if (_offset == -1) {
duke@435 338 // at creation we couldn't link to our holder so we need to
duke@435 339 // maintain that stance, otherwise there's no safe way to use this
duke@435 340 // ciField.
duke@435 341 return false;
duke@435 342 }
duke@435 343
never@3854 344 // Check for static/nonstatic mismatch
never@3854 345 bool is_static = (bc == Bytecodes::_getstatic || bc == Bytecodes::_putstatic);
never@3854 346 if (is_static != this->is_static()) {
never@3854 347 return false;
never@3854 348 }
never@3854 349
never@3854 350 // Get and put can have different accessibility rules
never@3854 351 bool is_put = (bc == Bytecodes::_putfield || bc == Bytecodes::_putstatic);
never@3854 352 if (is_put) {
never@3854 353 if (_known_to_link_with_put == accessing_klass) {
never@3854 354 return true;
never@3854 355 }
never@3856 356 } else {
never@3854 357 if (_known_to_link_with_get == accessing_klass) {
never@3854 358 return true;
never@3854 359 }
duke@435 360 }
duke@435 361
drchase@5732 362 fieldDescriptor result;
drchase@5732 363 LinkResolver::resolve_field(result, _holder->get_instanceKlass(),
drchase@5732 364 _name->get_symbol(), _signature->get_symbol(),
drchase@5732 365 accessing_klass->get_Klass(), bc, true, false,
drchase@5732 366 KILL_COMPILE_ON_FATAL_(false));
duke@435 367
duke@435 368 // update the hit-cache, unless there is a problem with memory scoping:
never@3854 369 if (accessing_klass->is_shared() || !is_shared()) {
never@3854 370 if (is_put) {
never@3854 371 _known_to_link_with_put = accessing_klass;
never@3854 372 } else {
never@3854 373 _known_to_link_with_get = accessing_klass;
never@3854 374 }
never@3854 375 }
duke@435 376
duke@435 377 return true;
duke@435 378 }
duke@435 379
duke@435 380 // ------------------------------------------------------------------
duke@435 381 // ciField::print
duke@435 382 void ciField::print() {
roland@4357 383 tty->print("<ciField name=");
duke@435 384 _holder->print_name();
duke@435 385 tty->print(".");
duke@435 386 _name->print_symbol();
roland@4357 387 tty->print(" signature=");
roland@4357 388 _signature->print_symbol();
duke@435 389 tty->print(" offset=%d type=", _offset);
vlivanov@5658 390 if (_type != NULL)
vlivanov@5658 391 _type->print_name();
vlivanov@5658 392 else
vlivanov@5658 393 tty->print("(reference)");
vlivanov@5658 394 tty->print(" flags=%04x", flags().as_int());
duke@435 395 tty->print(" is_constant=%s", bool_to_str(_is_constant));
kvn@2037 396 if (_is_constant && is_static()) {
duke@435 397 tty->print(" constant_value=");
duke@435 398 _constant_value.print();
duke@435 399 }
duke@435 400 tty->print(">");
duke@435 401 }
duke@435 402
duke@435 403 // ------------------------------------------------------------------
duke@435 404 // ciField::print_name_on
duke@435 405 //
duke@435 406 // Print the name of this field
duke@435 407 void ciField::print_name_on(outputStream* st) {
duke@435 408 name()->print_symbol_on(st);
duke@435 409 }

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