| /* |
| * Copyright (c) 2003, 2016, 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 "classfile/stackMapTable.hpp" |
| #include "classfile/verifier.hpp" |
| #include "memory/resourceArea.hpp" |
| #include "oops/oop.inline.hpp" |
| #include "runtime/fieldType.hpp" |
| #include "runtime/handles.inline.hpp" |
| |
| StackMapTable::StackMapTable(StackMapReader* reader, StackMapFrame* init_frame, |
| u2 max_locals, u2 max_stack, |
| char* code_data, int code_len, TRAPS) { |
| _code_length = code_len; |
| _frame_count = reader->get_frame_count(); |
| if (_frame_count > 0) { |
| _frame_array = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, |
| StackMapFrame*, _frame_count); |
| StackMapFrame* pre_frame = init_frame; |
| for (int32_t i = 0; i < _frame_count; i++) { |
| StackMapFrame* frame = reader->next( |
| pre_frame, i == 0, max_locals, max_stack, |
| CHECK_VERIFY(pre_frame->verifier())); |
| _frame_array[i] = frame; |
| int offset = frame->offset(); |
| if (offset >= code_len || code_data[offset] == 0) { |
| frame->verifier()->verify_error( |
| ErrorContext::bad_stackmap(i, frame), |
| "StackMapTable error: bad offset"); |
| return; |
| } |
| pre_frame = frame; |
| } |
| } |
| reader->check_end(CHECK); |
| } |
| |
| // This method is only called by method in StackMapTable. |
| int StackMapTable::get_index_from_offset(int32_t offset) const { |
| int i = 0; |
| for (; i < _frame_count; i++) { |
| if (_frame_array[i]->offset() == offset) { |
| return i; |
| } |
| } |
| return i; // frame with offset doesn't exist in the array |
| } |
| |
| bool StackMapTable::match_stackmap( |
| StackMapFrame* frame, int32_t target, |
| bool match, bool update, ErrorContext* ctx, TRAPS) const { |
| int index = get_index_from_offset(target); |
| return match_stackmap(frame, target, index, match, update, ctx, THREAD); |
| } |
| |
| // Match and/or update current_frame to the frame in stackmap table with |
| // specified offset and frame index. Return true if the two frames match. |
| // |
| // The values of match and update are: _match__update |
| // |
| // checking a branch target: true false |
| // checking an exception handler: true false |
| // linear bytecode verification following an |
| // unconditional branch: false true |
| // linear bytecode verification not following an |
| // unconditional branch: true true |
| bool StackMapTable::match_stackmap( |
| StackMapFrame* frame, int32_t target, int32_t frame_index, |
| bool match, bool update, ErrorContext* ctx, TRAPS) const { |
| if (frame_index < 0 || frame_index >= _frame_count) { |
| *ctx = ErrorContext::missing_stackmap(frame->offset()); |
| frame->verifier()->verify_error( |
| *ctx, "Expecting a stackmap frame at branch target %d", target); |
| return false; |
| } |
| |
| StackMapFrame *stackmap_frame = _frame_array[frame_index]; |
| bool result = true; |
| if (match) { |
| // Has direct control flow from last instruction, need to match the two |
| // frames. |
| result = frame->is_assignable_to(stackmap_frame, |
| ctx, CHECK_VERIFY_(frame->verifier(), result)); |
| } |
| if (update) { |
| // Use the frame in stackmap table as current frame |
| int lsize = stackmap_frame->locals_size(); |
| int ssize = stackmap_frame->stack_size(); |
| if (frame->locals_size() > lsize || frame->stack_size() > ssize) { |
| // Make sure unused type array items are all _bogus_type. |
| frame->reset(); |
| } |
| frame->set_locals_size(lsize); |
| frame->copy_locals(stackmap_frame); |
| frame->set_stack_size(ssize); |
| frame->copy_stack(stackmap_frame); |
| frame->set_flags(stackmap_frame->flags()); |
| } |
| return result; |
| } |
| |
| void StackMapTable::check_jump_target( |
| StackMapFrame* frame, int32_t target, TRAPS) const { |
| ErrorContext ctx; |
| bool match = match_stackmap( |
| frame, target, true, false, &ctx, CHECK_VERIFY(frame->verifier())); |
| if (!match || (target < 0 || target >= _code_length)) { |
| frame->verifier()->verify_error(ctx, |
| "Inconsistent stackmap frames at branch target %d", target); |
| } |
| } |
| |
| void StackMapTable::print_on(outputStream* str) const { |
| str->indent().print_cr("StackMapTable: frame_count = %d", _frame_count); |
| str->indent().print_cr("table = { "); |
| { |
| streamIndentor si(str); |
| for (int32_t i = 0; i < _frame_count; ++i) { |
| _frame_array[i]->print_on(str); |
| } |
| } |
| str->print_cr(" }"); |
| } |
| |
| int32_t StackMapReader::chop( |
| VerificationType* locals, int32_t length, int32_t chops) { |
| if (locals == NULL) return -1; |
| int32_t pos = length - 1; |
| for (int32_t i=0; i<chops; i++) { |
| if (locals[pos].is_category2_2nd()) { |
| pos -= 2; |
| } else { |
| pos --; |
| } |
| if (pos<0 && i<(chops-1)) return -1; |
| } |
| return pos+1; |
| } |
| |
| VerificationType StackMapReader::parse_verification_type(u1* flags, TRAPS) { |
| u1 tag = _stream->get_u1(THREAD); |
| if (tag < (u1)ITEM_UninitializedThis) { |
| return VerificationType::from_tag(tag); |
| } |
| if (tag == ITEM_Object) { |
| u2 class_index = _stream->get_u2(THREAD); |
| int nconstants = _cp->length(); |
| if ((class_index <= 0 || class_index >= nconstants) || |
| (!_cp->tag_at(class_index).is_klass() && |
| !_cp->tag_at(class_index).is_unresolved_klass())) { |
| _stream->stackmap_format_error("bad class index", THREAD); |
| return VerificationType::bogus_type(); |
| } |
| return VerificationType::reference_type(_cp->klass_name_at(class_index)); |
| } |
| if (tag == ITEM_UninitializedThis) { |
| if (flags != NULL) { |
| *flags |= FLAG_THIS_UNINIT; |
| } |
| return VerificationType::uninitialized_this_type(); |
| } |
| if (tag == ITEM_Uninitialized) { |
| u2 offset = _stream->get_u2(THREAD); |
| if (offset >= _code_length || |
| _code_data[offset] != ClassVerifier::NEW_OFFSET) { |
| _verifier->class_format_error( |
| "StackMapTable format error: bad offset for Uninitialized"); |
| return VerificationType::bogus_type(); |
| } |
| return VerificationType::uninitialized_type(offset); |
| } |
| _stream->stackmap_format_error("bad verification type", THREAD); |
| return VerificationType::bogus_type(); |
| } |
| |
| StackMapFrame* StackMapReader::next( |
| StackMapFrame* pre_frame, bool first, u2 max_locals, u2 max_stack, TRAPS) { |
| StackMapFrame* frame; |
| int offset; |
| VerificationType* locals = NULL; |
| u1 frame_type = _stream->get_u1(THREAD); |
| if (frame_type < 64) { |
| // same_frame |
| if (first) { |
| offset = frame_type; |
| // Can't share the locals array since that is updated by the verifier. |
| if (pre_frame->locals_size() > 0) { |
| locals = NEW_RESOURCE_ARRAY_IN_THREAD( |
| THREAD, VerificationType, pre_frame->locals_size()); |
| } |
| } else { |
| offset = pre_frame->offset() + frame_type + 1; |
| locals = pre_frame->locals(); |
| } |
| frame = new StackMapFrame( |
| offset, pre_frame->flags(), pre_frame->locals_size(), 0, |
| max_locals, max_stack, locals, NULL, _verifier); |
| if (first && locals != NULL) { |
| frame->copy_locals(pre_frame); |
| } |
| return frame; |
| } |
| if (frame_type < 128) { |
| // same_locals_1_stack_item_frame |
| if (first) { |
| offset = frame_type - 64; |
| // Can't share the locals array since that is updated by the verifier. |
| if (pre_frame->locals_size() > 0) { |
| locals = NEW_RESOURCE_ARRAY_IN_THREAD( |
| THREAD, VerificationType, pre_frame->locals_size()); |
| } |
| } else { |
| offset = pre_frame->offset() + frame_type - 63; |
| locals = pre_frame->locals(); |
| } |
| VerificationType* stack = NEW_RESOURCE_ARRAY_IN_THREAD( |
| THREAD, VerificationType, 2); |
| u2 stack_size = 1; |
| stack[0] = parse_verification_type(NULL, CHECK_VERIFY_(_verifier, NULL)); |
| if (stack[0].is_category2()) { |
| stack[1] = stack[0].to_category2_2nd(); |
| stack_size = 2; |
| } |
| check_verification_type_array_size( |
| stack_size, max_stack, CHECK_VERIFY_(_verifier, NULL)); |
| frame = new StackMapFrame( |
| offset, pre_frame->flags(), pre_frame->locals_size(), stack_size, |
| max_locals, max_stack, locals, stack, _verifier); |
| if (first && locals != NULL) { |
| frame->copy_locals(pre_frame); |
| } |
| return frame; |
| } |
| |
| u2 offset_delta = _stream->get_u2(THREAD); |
| |
| if (frame_type < SAME_LOCALS_1_STACK_ITEM_EXTENDED) { |
| // reserved frame types |
| _stream->stackmap_format_error( |
| "reserved frame type", CHECK_VERIFY_(_verifier, NULL)); |
| } |
| |
| if (frame_type == SAME_LOCALS_1_STACK_ITEM_EXTENDED) { |
| // same_locals_1_stack_item_frame_extended |
| if (first) { |
| offset = offset_delta; |
| // Can't share the locals array since that is updated by the verifier. |
| if (pre_frame->locals_size() > 0) { |
| locals = NEW_RESOURCE_ARRAY_IN_THREAD( |
| THREAD, VerificationType, pre_frame->locals_size()); |
| } |
| } else { |
| offset = pre_frame->offset() + offset_delta + 1; |
| locals = pre_frame->locals(); |
| } |
| VerificationType* stack = NEW_RESOURCE_ARRAY_IN_THREAD( |
| THREAD, VerificationType, 2); |
| u2 stack_size = 1; |
| stack[0] = parse_verification_type(NULL, CHECK_VERIFY_(_verifier, NULL)); |
| if (stack[0].is_category2()) { |
| stack[1] = stack[0].to_category2_2nd(); |
| stack_size = 2; |
| } |
| check_verification_type_array_size( |
| stack_size, max_stack, CHECK_VERIFY_(_verifier, NULL)); |
| frame = new StackMapFrame( |
| offset, pre_frame->flags(), pre_frame->locals_size(), stack_size, |
| max_locals, max_stack, locals, stack, _verifier); |
| if (first && locals != NULL) { |
| frame->copy_locals(pre_frame); |
| } |
| return frame; |
| } |
| |
| if (frame_type <= SAME_EXTENDED) { |
| // chop_frame or same_frame_extended |
| locals = pre_frame->locals(); |
| int length = pre_frame->locals_size(); |
| int chops = SAME_EXTENDED - frame_type; |
| int new_length = length; |
| u1 flags = pre_frame->flags(); |
| if (chops != 0) { |
| new_length = chop(locals, length, chops); |
| check_verification_type_array_size( |
| new_length, max_locals, CHECK_VERIFY_(_verifier, NULL)); |
| // Recompute flags since uninitializedThis could have been chopped. |
| flags = 0; |
| for (int i=0; i<new_length; i++) { |
| if (locals[i].is_uninitialized_this()) { |
| flags |= FLAG_THIS_UNINIT; |
| break; |
| } |
| } |
| } |
| if (first) { |
| offset = offset_delta; |
| // Can't share the locals array since that is updated by the verifier. |
| if (new_length > 0) { |
| locals = NEW_RESOURCE_ARRAY_IN_THREAD( |
| THREAD, VerificationType, new_length); |
| } else { |
| locals = NULL; |
| } |
| } else { |
| offset = pre_frame->offset() + offset_delta + 1; |
| } |
| frame = new StackMapFrame( |
| offset, flags, new_length, 0, max_locals, max_stack, |
| locals, NULL, _verifier); |
| if (first && locals != NULL) { |
| frame->copy_locals(pre_frame); |
| } |
| return frame; |
| } else if (frame_type < SAME_EXTENDED + 4) { |
| // append_frame |
| int appends = frame_type - SAME_EXTENDED; |
| int real_length = pre_frame->locals_size(); |
| int new_length = real_length + appends*2; |
| locals = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, VerificationType, new_length); |
| VerificationType* pre_locals = pre_frame->locals(); |
| int i; |
| for (i=0; i<pre_frame->locals_size(); i++) { |
| locals[i] = pre_locals[i]; |
| } |
| u1 flags = pre_frame->flags(); |
| for (i=0; i<appends; i++) { |
| locals[real_length] = parse_verification_type(&flags, THREAD); |
| if (locals[real_length].is_category2()) { |
| locals[real_length + 1] = locals[real_length].to_category2_2nd(); |
| ++real_length; |
| } |
| ++real_length; |
| } |
| check_verification_type_array_size( |
| real_length, max_locals, CHECK_VERIFY_(_verifier, NULL)); |
| if (first) { |
| offset = offset_delta; |
| } else { |
| offset = pre_frame->offset() + offset_delta + 1; |
| } |
| frame = new StackMapFrame( |
| offset, flags, real_length, 0, max_locals, |
| max_stack, locals, NULL, _verifier); |
| return frame; |
| } |
| if (frame_type == FULL) { |
| // full_frame |
| u1 flags = 0; |
| u2 locals_size = _stream->get_u2(THREAD); |
| int real_locals_size = 0; |
| if (locals_size > 0) { |
| locals = NEW_RESOURCE_ARRAY_IN_THREAD( |
| THREAD, VerificationType, locals_size*2); |
| } |
| int i; |
| for (i=0; i<locals_size; i++) { |
| locals[real_locals_size] = parse_verification_type(&flags, THREAD); |
| if (locals[real_locals_size].is_category2()) { |
| locals[real_locals_size + 1] = |
| locals[real_locals_size].to_category2_2nd(); |
| ++real_locals_size; |
| } |
| ++real_locals_size; |
| } |
| check_verification_type_array_size( |
| real_locals_size, max_locals, CHECK_VERIFY_(_verifier, NULL)); |
| u2 stack_size = _stream->get_u2(THREAD); |
| int real_stack_size = 0; |
| VerificationType* stack = NULL; |
| if (stack_size > 0) { |
| stack = NEW_RESOURCE_ARRAY_IN_THREAD( |
| THREAD, VerificationType, stack_size*2); |
| } |
| for (i=0; i<stack_size; i++) { |
| stack[real_stack_size] = parse_verification_type(NULL, THREAD); |
| if (stack[real_stack_size].is_category2()) { |
| stack[real_stack_size + 1] = stack[real_stack_size].to_category2_2nd(); |
| ++real_stack_size; |
| } |
| ++real_stack_size; |
| } |
| check_verification_type_array_size( |
| real_stack_size, max_stack, CHECK_VERIFY_(_verifier, NULL)); |
| if (first) { |
| offset = offset_delta; |
| } else { |
| offset = pre_frame->offset() + offset_delta + 1; |
| } |
| frame = new StackMapFrame( |
| offset, flags, real_locals_size, real_stack_size, |
| max_locals, max_stack, locals, stack, _verifier); |
| return frame; |
| } |
| |
| _stream->stackmap_format_error( |
| "reserved frame type", CHECK_VERIFY_(pre_frame->verifier(), NULL)); |
| return NULL; |
| } |