method_verifier.h revision eb8167a4f4d27fce0530f6724ab8032610cd146b
1/* 2 * Copyright (C) 2011 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17#ifndef ART_RUNTIME_VERIFIER_METHOD_VERIFIER_H_ 18#define ART_RUNTIME_VERIFIER_METHOD_VERIFIER_H_ 19 20#include <set> 21#include <vector> 22 23#include "base/casts.h" 24#include "base/macros.h" 25#include "base/stl_util.h" 26#include "class_reference.h" 27#include "dex_file.h" 28#include "dex_instruction.h" 29#include "instruction_flags.h" 30#include "method_reference.h" 31#include "mirror/object.h" 32#include "reg_type.h" 33#include "reg_type_cache-inl.h" 34#include "register_line.h" 35#include "safe_map.h" 36#include "UniquePtr.h" 37 38namespace art { 39 40struct ReferenceMap2Visitor; 41template<class T> class Handle; 42 43namespace verifier { 44 45class MethodVerifier; 46class DexPcToReferenceMap; 47 48/* 49 * "Direct" and "virtual" methods are stored independently. The type of call used to invoke the 50 * method determines which list we search, and whether we travel up into superclasses. 51 * 52 * (<clinit>, <init>, and methods declared "private" or "static" are stored in the "direct" list. 53 * All others are stored in the "virtual" list.) 54 */ 55enum MethodType { 56 METHOD_UNKNOWN = 0, 57 METHOD_DIRECT, // <init>, private 58 METHOD_STATIC, // static 59 METHOD_VIRTUAL, // virtual, super 60 METHOD_INTERFACE // interface 61}; 62std::ostream& operator<<(std::ostream& os, const MethodType& rhs); 63 64/* 65 * An enumeration of problems that can turn up during verification. 66 * Both VERIFY_ERROR_BAD_CLASS_SOFT and VERIFY_ERROR_BAD_CLASS_HARD denote failures that cause 67 * the entire class to be rejected. However, VERIFY_ERROR_BAD_CLASS_SOFT denotes a soft failure 68 * that can potentially be corrected, and the verifier will try again at runtime. 69 * VERIFY_ERROR_BAD_CLASS_HARD denotes a hard failure that can't be corrected, and will cause 70 * the class to remain uncompiled. Other errors denote verification errors that cause bytecode 71 * to be rewritten to fail at runtime. 72 */ 73enum VerifyError { 74 VERIFY_ERROR_BAD_CLASS_HARD, // VerifyError; hard error that skips compilation. 75 VERIFY_ERROR_BAD_CLASS_SOFT, // VerifyError; soft error that verifies again at runtime. 76 77 VERIFY_ERROR_NO_CLASS, // NoClassDefFoundError. 78 VERIFY_ERROR_NO_FIELD, // NoSuchFieldError. 79 VERIFY_ERROR_NO_METHOD, // NoSuchMethodError. 80 VERIFY_ERROR_ACCESS_CLASS, // IllegalAccessError. 81 VERIFY_ERROR_ACCESS_FIELD, // IllegalAccessError. 82 VERIFY_ERROR_ACCESS_METHOD, // IllegalAccessError. 83 VERIFY_ERROR_CLASS_CHANGE, // IncompatibleClassChangeError. 84 VERIFY_ERROR_INSTANTIATION, // InstantiationError. 85}; 86std::ostream& operator<<(std::ostream& os, const VerifyError& rhs); 87 88/* 89 * Identifies the type of reference in the instruction that generated the verify error 90 * (e.g. VERIFY_ERROR_ACCESS_CLASS could come from a method, field, or class reference). 91 * 92 * This must fit in two bits. 93 */ 94enum VerifyErrorRefType { 95 VERIFY_ERROR_REF_CLASS = 0, 96 VERIFY_ERROR_REF_FIELD = 1, 97 VERIFY_ERROR_REF_METHOD = 2, 98}; 99const int kVerifyErrorRefTypeShift = 6; 100 101// We don't need to store the register data for many instructions, because we either only need 102// it at branch points (for verification) or GC points and branches (for verification + 103// type-precise register analysis). 104enum RegisterTrackingMode { 105 kTrackRegsBranches, 106 kTrackCompilerInterestPoints, 107 kTrackRegsAll, 108}; 109 110// A mapping from a dex pc to the register line statuses as they are immediately prior to the 111// execution of that instruction. 112class PcToRegisterLineTable { 113 public: 114 PcToRegisterLineTable() : size_(0) {} 115 ~PcToRegisterLineTable(); 116 117 // Initialize the RegisterTable. Every instruction address can have a different set of information 118 // about what's in which register, but for verification purposes we only need to store it at 119 // branch target addresses (because we merge into that). 120 void Init(RegisterTrackingMode mode, InstructionFlags* flags, uint32_t insns_size, 121 uint16_t registers_size, MethodVerifier* verifier); 122 123 RegisterLine* GetLine(size_t idx) { 124 DCHECK_LT(idx, size_); 125 return register_lines_[idx]; 126 } 127 128 private: 129 UniquePtr<RegisterLine*[]> register_lines_; 130 size_t size_; 131}; 132 133// The verifier 134class MethodVerifier { 135 public: 136 enum FailureKind { 137 kNoFailure, 138 kSoftFailure, 139 kHardFailure, 140 }; 141 142 /* Verify a class. Returns "kNoFailure" on success. */ 143 static FailureKind VerifyClass(mirror::Class* klass, bool allow_soft_failures, std::string* error) 144 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 145 static FailureKind VerifyClass(const DexFile* dex_file, Handle<mirror::DexCache>& dex_cache, 146 Handle<mirror::ClassLoader>& class_loader, 147 const DexFile::ClassDef* class_def, 148 bool allow_soft_failures, std::string* error) 149 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 150 151 static void VerifyMethodAndDump(std::ostream& os, uint32_t method_idx, const DexFile* dex_file, 152 Handle<mirror::DexCache>& dex_cache, 153 Handle<mirror::ClassLoader>& class_loader, 154 const DexFile::ClassDef* class_def, 155 const DexFile::CodeItem* code_item, 156 mirror::ArtMethod* method, uint32_t method_access_flags) 157 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 158 159 uint8_t EncodePcToReferenceMapData() const; 160 161 uint32_t DexFileVersion() const { 162 return dex_file_->GetVersion(); 163 } 164 165 RegTypeCache* GetRegTypeCache() { 166 return ®_types_; 167 } 168 169 // Log a verification failure. 170 std::ostream& Fail(VerifyError error); 171 172 // Log for verification information. 173 std::ostream& LogVerifyInfo() { 174 return info_messages_ << "VFY: " << PrettyMethod(dex_method_idx_, *dex_file_) 175 << '[' << reinterpret_cast<void*>(work_insn_idx_) << "] : "; 176 } 177 178 // Dump the failures encountered by the verifier. 179 std::ostream& DumpFailures(std::ostream& os); 180 181 // Dump the state of the verifier, namely each instruction, what flags are set on it, register 182 // information 183 void Dump(std::ostream& os) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 184 185 // Fills 'monitor_enter_dex_pcs' with the dex pcs of the monitor-enter instructions corresponding 186 // to the locks held at 'dex_pc' in method 'm'. 187 static void FindLocksAtDexPc(mirror::ArtMethod* m, uint32_t dex_pc, 188 std::vector<uint32_t>& monitor_enter_dex_pcs) 189 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 190 191 // Returns the accessed field corresponding to the quick instruction's field 192 // offset at 'dex_pc' in method 'm'. 193 static mirror::ArtField* FindAccessedFieldAtDexPc(mirror::ArtMethod* m, uint32_t dex_pc) 194 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 195 196 // Returns the invoked method corresponding to the quick instruction's vtable 197 // index at 'dex_pc' in method 'm'. 198 static mirror::ArtMethod* FindInvokedMethodAtDexPc(mirror::ArtMethod* m, uint32_t dex_pc) 199 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 200 201 static void Init() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 202 static void Shutdown(); 203 204 bool CanLoadClasses() const { 205 return can_load_classes_; 206 } 207 208 MethodVerifier(const DexFile* dex_file, Handle<mirror::DexCache>* dex_cache, 209 Handle<mirror::ClassLoader>* class_loader, const DexFile::ClassDef* class_def, 210 const DexFile::CodeItem* code_item, uint32_t method_idx, mirror::ArtMethod* method, 211 uint32_t access_flags, bool can_load_classes, bool allow_soft_failures) 212 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 213 214 ~MethodVerifier(); 215 216 // Run verification on the method. Returns true if verification completes and false if the input 217 // has an irrecoverable corruption. 218 bool Verify() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 219 220 // Describe VRegs at the given dex pc. 221 std::vector<int32_t> DescribeVRegs(uint32_t dex_pc); 222 223 void VisitRoots(RootCallback* callback, void* arg) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 224 225 // Accessors used by the compiler via CompilerCallback 226 const DexFile::CodeItem* CodeItem() const; 227 RegisterLine* GetRegLine(uint32_t dex_pc); 228 const InstructionFlags& GetInstructionFlags(size_t index) const; 229 mirror::ClassLoader* GetClassLoader() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 230 mirror::DexCache* GetDexCache() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 231 MethodReference GetMethodReference() const; 232 uint32_t GetAccessFlags() const; 233 bool HasCheckCasts() const; 234 bool HasVirtualOrInterfaceInvokes() const; 235 bool HasFailures() const; 236 const RegType& ResolveCheckedClass(uint32_t class_idx) 237 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 238 239 private: 240 // Adds the given string to the beginning of the last failure message. 241 void PrependToLastFailMessage(std::string); 242 243 // Adds the given string to the end of the last failure message. 244 void AppendToLastFailMessage(std::string); 245 246 /* 247 * Perform verification on a single method. 248 * 249 * We do this in three passes: 250 * (1) Walk through all code units, determining instruction locations, 251 * widths, and other characteristics. 252 * (2) Walk through all code units, performing static checks on 253 * operands. 254 * (3) Iterate through the method, checking type safety and looking 255 * for code flow problems. 256 */ 257 static FailureKind VerifyMethod(uint32_t method_idx, const DexFile* dex_file, 258 Handle<mirror::DexCache>& dex_cache, 259 Handle<mirror::ClassLoader>& class_loader, 260 const DexFile::ClassDef* class_def_idx, 261 const DexFile::CodeItem* code_item, 262 mirror::ArtMethod* method, uint32_t method_access_flags, 263 bool allow_soft_failures) 264 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 265 266 void FindLocksAtDexPc() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 267 268 mirror::ArtField* FindAccessedFieldAtDexPc(uint32_t dex_pc) 269 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 270 271 mirror::ArtMethod* FindInvokedMethodAtDexPc(uint32_t dex_pc) 272 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 273 274 /* 275 * Compute the width of the instruction at each address in the instruction stream, and store it in 276 * insn_flags_. Addresses that are in the middle of an instruction, or that are part of switch 277 * table data, are not touched (so the caller should probably initialize "insn_flags" to zero). 278 * 279 * The "new_instance_count_" and "monitor_enter_count_" fields in vdata are also set. 280 * 281 * Performs some static checks, notably: 282 * - opcode of first instruction begins at index 0 283 * - only documented instructions may appear 284 * - each instruction follows the last 285 * - last byte of last instruction is at (code_length-1) 286 * 287 * Logs an error and returns "false" on failure. 288 */ 289 bool ComputeWidthsAndCountOps(); 290 291 /* 292 * Set the "in try" flags for all instructions protected by "try" statements. Also sets the 293 * "branch target" flags for exception handlers. 294 * 295 * Call this after widths have been set in "insn_flags". 296 * 297 * Returns "false" if something in the exception table looks fishy, but we're expecting the 298 * exception table to be somewhat sane. 299 */ 300 bool ScanTryCatchBlocks() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 301 302 /* 303 * Perform static verification on all instructions in a method. 304 * 305 * Walks through instructions in a method calling VerifyInstruction on each. 306 */ 307 bool VerifyInstructions(); 308 309 /* 310 * Perform static verification on an instruction. 311 * 312 * As a side effect, this sets the "branch target" flags in InsnFlags. 313 * 314 * "(CF)" items are handled during code-flow analysis. 315 * 316 * v3 4.10.1 317 * - target of each jump and branch instruction must be valid 318 * - targets of switch statements must be valid 319 * - operands referencing constant pool entries must be valid 320 * - (CF) operands of getfield, putfield, getstatic, putstatic must be valid 321 * - (CF) operands of method invocation instructions must be valid 322 * - (CF) only invoke-direct can call a method starting with '<' 323 * - (CF) <clinit> must never be called explicitly 324 * - operands of instanceof, checkcast, new (and variants) must be valid 325 * - new-array[-type] limited to 255 dimensions 326 * - can't use "new" on an array class 327 * - (?) limit dimensions in multi-array creation 328 * - local variable load/store register values must be in valid range 329 * 330 * v3 4.11.1.2 331 * - branches must be within the bounds of the code array 332 * - targets of all control-flow instructions are the start of an instruction 333 * - register accesses fall within range of allocated registers 334 * - (N/A) access to constant pool must be of appropriate type 335 * - code does not end in the middle of an instruction 336 * - execution cannot fall off the end of the code 337 * - (earlier) for each exception handler, the "try" area must begin and 338 * end at the start of an instruction (end can be at the end of the code) 339 * - (earlier) for each exception handler, the handler must start at a valid 340 * instruction 341 */ 342 bool VerifyInstruction(const Instruction* inst, uint32_t code_offset); 343 344 /* Ensure that the register index is valid for this code item. */ 345 bool CheckRegisterIndex(uint32_t idx); 346 347 /* Ensure that the wide register index is valid for this code item. */ 348 bool CheckWideRegisterIndex(uint32_t idx); 349 350 // Perform static checks on a field Get or set instruction. All we do here is ensure that the 351 // field index is in the valid range. 352 bool CheckFieldIndex(uint32_t idx); 353 354 // Perform static checks on a method invocation instruction. All we do here is ensure that the 355 // method index is in the valid range. 356 bool CheckMethodIndex(uint32_t idx); 357 358 // Perform static checks on a "new-instance" instruction. Specifically, make sure the class 359 // reference isn't for an array class. 360 bool CheckNewInstance(uint32_t idx); 361 362 /* Ensure that the string index is in the valid range. */ 363 bool CheckStringIndex(uint32_t idx); 364 365 // Perform static checks on an instruction that takes a class constant. Ensure that the class 366 // index is in the valid range. 367 bool CheckTypeIndex(uint32_t idx); 368 369 // Perform static checks on a "new-array" instruction. Specifically, make sure they aren't 370 // creating an array of arrays that causes the number of dimensions to exceed 255. 371 bool CheckNewArray(uint32_t idx); 372 373 // Verify an array data table. "cur_offset" is the offset of the fill-array-data instruction. 374 bool CheckArrayData(uint32_t cur_offset); 375 376 // Verify that the target of a branch instruction is valid. We don't expect code to jump directly 377 // into an exception handler, but it's valid to do so as long as the target isn't a 378 // "move-exception" instruction. We verify that in a later stage. 379 // The dex format forbids certain instructions from branching to themselves. 380 // Updates "insn_flags_", setting the "branch target" flag. 381 bool CheckBranchTarget(uint32_t cur_offset); 382 383 // Verify a switch table. "cur_offset" is the offset of the switch instruction. 384 // Updates "insn_flags_", setting the "branch target" flag. 385 bool CheckSwitchTargets(uint32_t cur_offset); 386 387 // Check the register indices used in a "vararg" instruction, such as invoke-virtual or 388 // filled-new-array. 389 // - vA holds word count (0-5), args[] have values. 390 // There are some tests we don't do here, e.g. we don't try to verify that invoking a method that 391 // takes a double is done with consecutive registers. This requires parsing the target method 392 // signature, which we will be doing later on during the code flow analysis. 393 bool CheckVarArgRegs(uint32_t vA, uint32_t arg[]); 394 395 // Check the register indices used in a "vararg/range" instruction, such as invoke-virtual/range 396 // or filled-new-array/range. 397 // - vA holds word count, vC holds index of first reg. 398 bool CheckVarArgRangeRegs(uint32_t vA, uint32_t vC); 399 400 // Extract the relative offset from a branch instruction. 401 // Returns "false" on failure (e.g. this isn't a branch instruction). 402 bool GetBranchOffset(uint32_t cur_offset, int32_t* pOffset, bool* pConditional, 403 bool* selfOkay); 404 405 /* Perform detailed code-flow analysis on a single method. */ 406 bool VerifyCodeFlow() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 407 408 // Set the register types for the first instruction in the method based on the method signature. 409 // This has the side-effect of validating the signature. 410 bool SetTypesFromSignature() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 411 412 /* 413 * Perform code flow on a method. 414 * 415 * The basic strategy is as outlined in v3 4.11.1.2: set the "changed" bit on the first 416 * instruction, process it (setting additional "changed" bits), and repeat until there are no 417 * more. 418 * 419 * v3 4.11.1.1 420 * - (N/A) operand stack is always the same size 421 * - operand stack [registers] contain the correct types of values 422 * - local variables [registers] contain the correct types of values 423 * - methods are invoked with the appropriate arguments 424 * - fields are assigned using values of appropriate types 425 * - opcodes have the correct type values in operand registers 426 * - there is never an uninitialized class instance in a local variable in code protected by an 427 * exception handler (operand stack is okay, because the operand stack is discarded when an 428 * exception is thrown) [can't know what's a local var w/o the debug info -- should fall out of 429 * register typing] 430 * 431 * v3 4.11.1.2 432 * - execution cannot fall off the end of the code 433 * 434 * (We also do many of the items described in the "static checks" sections, because it's easier to 435 * do them here.) 436 * 437 * We need an array of RegType values, one per register, for every instruction. If the method uses 438 * monitor-enter, we need extra data for every register, and a stack for every "interesting" 439 * instruction. In theory this could become quite large -- up to several megabytes for a monster 440 * function. 441 * 442 * NOTE: 443 * The spec forbids backward branches when there's an uninitialized reference in a register. The 444 * idea is to prevent something like this: 445 * loop: 446 * move r1, r0 447 * new-instance r0, MyClass 448 * ... 449 * if-eq rN, loop // once 450 * initialize r0 451 * 452 * This leaves us with two different instances, both allocated by the same instruction, but only 453 * one is initialized. The scheme outlined in v3 4.11.1.4 wouldn't catch this, so they work around 454 * it by preventing backward branches. We achieve identical results without restricting code 455 * reordering by specifying that you can't execute the new-instance instruction if a register 456 * contains an uninitialized instance created by that same instruction. 457 */ 458 bool CodeFlowVerifyMethod() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 459 460 /* 461 * Perform verification for a single instruction. 462 * 463 * This requires fully decoding the instruction to determine the effect it has on registers. 464 * 465 * Finds zero or more following instructions and sets the "changed" flag if execution at that 466 * point needs to be (re-)evaluated. Register changes are merged into "reg_types_" at the target 467 * addresses. Does not set or clear any other flags in "insn_flags_". 468 */ 469 bool CodeFlowVerifyInstruction(uint32_t* start_guess) 470 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 471 472 // Perform verification of a new array instruction 473 void VerifyNewArray(const Instruction* inst, bool is_filled, bool is_range) 474 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 475 476 // Helper to perform verification on puts of primitive type. 477 void VerifyPrimitivePut(const RegType& target_type, const RegType& insn_type, 478 const uint32_t vregA) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 479 480 // Perform verification of an aget instruction. The destination register's type will be set to 481 // be that of component type of the array unless the array type is unknown, in which case a 482 // bottom type inferred from the type of instruction is used. is_primitive is false for an 483 // aget-object. 484 void VerifyAGet(const Instruction* inst, const RegType& insn_type, 485 bool is_primitive) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 486 487 // Perform verification of an aput instruction. 488 void VerifyAPut(const Instruction* inst, const RegType& insn_type, 489 bool is_primitive) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 490 491 // Lookup instance field and fail for resolution violations 492 mirror::ArtField* GetInstanceField(const RegType& obj_type, int field_idx) 493 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 494 495 // Lookup static field and fail for resolution violations 496 mirror::ArtField* GetStaticField(int field_idx) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 497 498 // Perform verification of an iget or sget instruction. 499 void VerifyISGet(const Instruction* inst, const RegType& insn_type, 500 bool is_primitive, bool is_static) 501 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 502 503 // Perform verification of an iput or sput instruction. 504 void VerifyISPut(const Instruction* inst, const RegType& insn_type, 505 bool is_primitive, bool is_static) 506 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 507 508 // Returns the access field of a quick field access (iget/iput-quick) or NULL 509 // if it cannot be found. 510 mirror::ArtField* GetQuickFieldAccess(const Instruction* inst, RegisterLine* reg_line) 511 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 512 513 // Perform verification of an iget-quick instruction. 514 void VerifyIGetQuick(const Instruction* inst, const RegType& insn_type, 515 bool is_primitive) 516 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 517 518 // Perform verification of an iput-quick instruction. 519 void VerifyIPutQuick(const Instruction* inst, const RegType& insn_type, 520 bool is_primitive) 521 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 522 523 // Resolves a class based on an index and performs access checks to ensure the referrer can 524 // access the resolved class. 525 const RegType& ResolveClassAndCheckAccess(uint32_t class_idx) 526 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 527 528 /* 529 * For the "move-exception" instruction at "work_insn_idx_", which must be at an exception handler 530 * address, determine the Join of all exceptions that can land here. Fails if no matching 531 * exception handler can be found or if the Join of exception types fails. 532 */ 533 const RegType& GetCaughtExceptionType() 534 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 535 536 /* 537 * Resolves a method based on an index and performs access checks to ensure 538 * the referrer can access the resolved method. 539 * Does not throw exceptions. 540 */ 541 mirror::ArtMethod* ResolveMethodAndCheckAccess(uint32_t method_idx, MethodType method_type) 542 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 543 544 /* 545 * Verify the arguments to a method. We're executing in "method", making 546 * a call to the method reference in vB. 547 * 548 * If this is a "direct" invoke, we allow calls to <init>. For calls to 549 * <init>, the first argument may be an uninitialized reference. Otherwise, 550 * calls to anything starting with '<' will be rejected, as will any 551 * uninitialized reference arguments. 552 * 553 * For non-static method calls, this will verify that the method call is 554 * appropriate for the "this" argument. 555 * 556 * The method reference is in vBBBB. The "is_range" parameter determines 557 * whether we use 0-4 "args" values or a range of registers defined by 558 * vAA and vCCCC. 559 * 560 * Widening conversions on integers and references are allowed, but 561 * narrowing conversions are not. 562 * 563 * Returns the resolved method on success, NULL on failure (with *failure 564 * set appropriately). 565 */ 566 mirror::ArtMethod* VerifyInvocationArgs(const Instruction* inst, 567 MethodType method_type, 568 bool is_range, bool is_super) 569 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 570 571 mirror::ArtMethod* GetQuickInvokedMethod(const Instruction* inst, 572 RegisterLine* reg_line, 573 bool is_range) 574 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 575 576 mirror::ArtMethod* VerifyInvokeVirtualQuickArgs(const Instruction* inst, bool is_range) 577 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 578 579 /* 580 * Verify that the target instruction is not "move-exception". It's important that the only way 581 * to execute a move-exception is as the first instruction of an exception handler. 582 * Returns "true" if all is well, "false" if the target instruction is move-exception. 583 */ 584 bool CheckNotMoveException(const uint16_t* insns, int insn_idx); 585 586 /* 587 * Control can transfer to "next_insn". Merge the registers from merge_line into the table at 588 * next_insn, and set the changed flag on the target address if any of the registers were changed. 589 * Returns "false" if an error is encountered. 590 */ 591 bool UpdateRegisters(uint32_t next_insn, const RegisterLine* merge_line) 592 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 593 594 // Is the method being verified a constructor? 595 bool IsConstructor() const { 596 return (method_access_flags_ & kAccConstructor) != 0; 597 } 598 599 // Is the method verified static? 600 bool IsStatic() const { 601 return (method_access_flags_ & kAccStatic) != 0; 602 } 603 604 // Return the register type for the method. 605 const RegType& GetMethodReturnType() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 606 607 // Get a type representing the declaring class of the method. 608 const RegType& GetDeclaringClass() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 609 610 InstructionFlags* CurrentInsnFlags(); 611 612 const RegType& DetermineCat1Constant(int32_t value, bool precise) 613 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 614 615 RegTypeCache reg_types_; 616 617 PcToRegisterLineTable reg_table_; 618 619 // Storage for the register status we're currently working on. 620 UniquePtr<RegisterLine> work_line_; 621 622 // The address of the instruction we're currently working on, note that this is in 2 byte 623 // quantities 624 uint32_t work_insn_idx_; 625 626 // Storage for the register status we're saving for later. 627 UniquePtr<RegisterLine> saved_line_; 628 629 const uint32_t dex_method_idx_; // The method we're working on. 630 // Its object representation if known. 631 mirror::ArtMethod* mirror_method_ GUARDED_BY(Locks::mutator_lock_); 632 const uint32_t method_access_flags_; // Method's access flags. 633 const RegType* return_type_; // Lazily computed return type of the method. 634 const DexFile* const dex_file_; // The dex file containing the method. 635 // The dex_cache for the declaring class of the method. 636 Handle<mirror::DexCache>* dex_cache_ GUARDED_BY(Locks::mutator_lock_); 637 // The class loader for the declaring class of the method. 638 Handle<mirror::ClassLoader>* class_loader_ GUARDED_BY(Locks::mutator_lock_); 639 const DexFile::ClassDef* const class_def_; // The class def of the declaring class of the method. 640 const DexFile::CodeItem* const code_item_; // The code item containing the code for the method. 641 const RegType* declaring_class_; // Lazily computed reg type of the method's declaring class. 642 // Instruction widths and flags, one entry per code unit. 643 UniquePtr<InstructionFlags[]> insn_flags_; 644 // The dex PC of a FindLocksAtDexPc request, -1 otherwise. 645 uint32_t interesting_dex_pc_; 646 // The container into which FindLocksAtDexPc should write the registers containing held locks, 647 // NULL if we're not doing FindLocksAtDexPc. 648 std::vector<uint32_t>* monitor_enter_dex_pcs_; 649 650 // The types of any error that occurs. 651 std::vector<VerifyError> failures_; 652 // Error messages associated with failures. 653 std::vector<std::ostringstream*> failure_messages_; 654 // Is there a pending hard failure? 655 bool have_pending_hard_failure_; 656 // Is there a pending runtime throw failure? A runtime throw failure is when an instruction 657 // would fail at runtime throwing an exception. Such an instruction causes the following code 658 // to be unreachable. This is set by Fail and used to ensure we don't process unreachable 659 // instructions that would hard fail the verification. 660 bool have_pending_runtime_throw_failure_; 661 662 // Info message log use primarily for verifier diagnostics. 663 std::ostringstream info_messages_; 664 665 // The number of occurrences of specific opcodes. 666 size_t new_instance_count_; 667 size_t monitor_enter_count_; 668 669 const bool can_load_classes_; 670 671 // Converts soft failures to hard failures when false. Only false when the compiler isn't 672 // running and the verifier is called from the class linker. 673 const bool allow_soft_failures_; 674 675 // Indicates the method being verified contains at least one check-cast or aput-object 676 // instruction. Aput-object operations implicitly check for array-store exceptions, similar to 677 // check-cast. 678 bool has_check_casts_; 679 680 // Indicates the method being verified contains at least one invoke-virtual/range 681 // or invoke-interface/range. 682 bool has_virtual_or_interface_invokes_; 683}; 684std::ostream& operator<<(std::ostream& os, const MethodVerifier::FailureKind& rhs); 685 686} // namespace verifier 687} // namespace art 688 689#endif // ART_RUNTIME_VERIFIER_METHOD_VERIFIER_H_ 690