1 /*
2 * Copyright (c) 2003, 2025, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "classfile/stackMapFrame.hpp"
26 #include "classfile/verifier.hpp"
27 #include "classfile/vmSymbols.hpp"
28 #include "memory/resourceArea.hpp"
29 #include "oops/oop.inline.hpp"
30 #include "oops/symbol.hpp"
31 #include "runtime/handles.inline.hpp"
32 #include "utilities/globalDefinitions.hpp"
33
34 StackMapFrame::StackMapFrame(u2 max_locals, u2 max_stack, AssertUnsetFieldTable* initial_strict_fields, ClassVerifier* v) :
35 _offset(0), _locals_size(0), _stack_size(0),
36 _stack_mark(0), _max_locals(max_locals),
37 _max_stack(max_stack), _flags(0), _assert_unset_fields(initial_strict_fields), _verifier(v) {
38 Thread* thr = v->thread();
39 _locals = NEW_RESOURCE_ARRAY_IN_THREAD(thr, VerificationType, max_locals);
40 _stack = NEW_RESOURCE_ARRAY_IN_THREAD(thr, VerificationType, max_stack);
41 int32_t i;
42 for(i = 0; i < max_locals; i++) {
43 _locals[i] = VerificationType::bogus_type();
44 }
45 for(i = 0; i < max_stack; i++) {
46 _stack[i] = VerificationType::bogus_type();
47 }
48 }
49
50 void StackMapFrame::unsatisfied_strict_fields_error(InstanceKlass* klass, int bci) {
51 Symbol* name;
52 Symbol* sig;
53 int num_uninit_fields = 0;
54
55 auto find_unset = [&] (const NameAndSig& key, const bool& value) {
56 if (!value) {
57 name = key._name;
58 sig = key._signature;
59 num_uninit_fields++;
60 }
61 };
62 assert_unset_fields()->iterate_all(find_unset);
63
64 verifier()->verify_error(
65 ErrorContext::bad_strict_fields(bci, this),
66 "All strict final fields must be initialized before super(): %d field(s), %s:%s in %s",
67 num_uninit_fields,
68 name->as_C_string(),
69 sig->as_C_string(),
70 klass->name()->as_C_string()
71 );
72 }
73
74 void StackMapFrame::print_strict_fields(AssertUnsetFieldTable* table) {
75 ResourceMark rm;
76 auto printfields = [&] (const NameAndSig& key, const bool& value) {
77 log_info(verification)("Strict field: %s%s (Satisfied: %s)",
78 key._name->as_C_string(),
79 key._signature->as_C_string(),
80 value ? "true" : "false");
81 };
82 table->iterate_all(printfields);
83 }
84
85 StackMapFrame* StackMapFrame::frame_in_exception_handler(u1 flags) {
86 Thread* thr = _verifier->thread();
87 VerificationType* stack = NEW_RESOURCE_ARRAY_IN_THREAD(thr, VerificationType, 1);
88 StackMapFrame* frame = new StackMapFrame(_offset, flags, _locals_size, 0,
89 _max_locals, _max_stack, _locals, stack,
90 _assert_unset_fields, _verifier);
91 return frame;
92 }
93
94 void StackMapFrame::initialize_object(
95 VerificationType old_object, VerificationType new_object) {
96 int32_t i;
97 for (i = 0; i < _max_locals; i++) {
98 if (_locals[i].equals(old_object)) {
99 _locals[i] = new_object;
100 }
101 }
102 for (i = 0; i < _stack_size; i++) {
103 if (_stack[i].equals(old_object)) {
104 _stack[i] = new_object;
105 }
106 }
107 if (old_object == VerificationType::uninitialized_this_type()) {
108 // "this" has been initialized - reset flags
109 _flags = 0;
110 }
111 }
112
113 VerificationType StackMapFrame::set_locals_from_arg(
114 const methodHandle& m, VerificationType thisKlass) {
115 SignatureStream ss(m->signature());
116 int init_local_num = 0;
117 if (!m->is_static()) {
118 init_local_num++;
119 // add one extra argument for instance method
120 if (m->is_object_constructor() &&
121 thisKlass.name() != vmSymbols::java_lang_Object()) {
122 _locals[0] = VerificationType::uninitialized_this_type();
123 _flags |= FLAG_THIS_UNINIT;
124 } else {
125 _locals[0] = thisKlass;
126 }
127 }
128
129 // local num may be greater than size of parameters because long/double occupies two slots
130 while(!ss.at_return_type()) {
131 init_local_num += _verifier->change_sig_to_verificationType(
132 &ss, &_locals[init_local_num]);
133 ss.next();
134 }
135 _locals_size = init_local_num;
136
137 switch (ss.type()) {
138 case T_OBJECT:
139 case T_ARRAY:
140 {
141 Symbol* sig = ss.as_symbol();
142 if (!sig->is_permanent()) {
143 // Create another symbol to save as signature stream unreferences
144 // this symbol.
145 Symbol *sig_copy =
146 verifier()->create_temporary_symbol(sig);
147 assert(sig_copy == sig, "symbols don't match");
148 sig = sig_copy;
149 }
150 return VerificationType::reference_type(sig);
151 }
152 case T_INT: return VerificationType::integer_type();
153 case T_BYTE: return VerificationType::byte_type();
154 case T_CHAR: return VerificationType::char_type();
155 case T_SHORT: return VerificationType::short_type();
156 case T_BOOLEAN: return VerificationType::boolean_type();
157 case T_FLOAT: return VerificationType::float_type();
158 case T_DOUBLE: return VerificationType::double_type();
159 case T_LONG: return VerificationType::long_type();
160 case T_VOID: return VerificationType::bogus_type();
161 default:
162 ShouldNotReachHere();
163 }
164 return VerificationType::bogus_type();
165 }
166
167 void StackMapFrame::copy_locals(const StackMapFrame* src) {
168 int32_t len = src->locals_size() < _locals_size ?
169 src->locals_size() : _locals_size;
170 for (int32_t i = 0; i < len; i++) {
171 _locals[i] = src->locals()[i];
172 }
173 }
174
175 void StackMapFrame::copy_stack(const StackMapFrame* src) {
176 int32_t len = src->stack_size() < _stack_size ?
177 src->stack_size() : _stack_size;
178 for (int32_t i = 0; i < len; i++) {
179 _stack[i] = src->stack()[i];
180 }
181 }
182
183 // Returns the location of the first mismatch, or 'len' if there are no
184 // mismatches
185 int StackMapFrame::is_assignable_to(
186 VerificationType* from, VerificationType* to, int32_t len, TRAPS) const {
187 int32_t i = 0;
188 for (i = 0; i < len; i++) {
189 if (!to[i].is_assignable_from(from[i], verifier(), false, THREAD)) {
190 break;
191 }
192 }
193 return i;
194 }
195
196 bool StackMapFrame::is_assignable_to(
197 const StackMapFrame* target, ErrorContext* ctx, TRAPS) const {
198 if (_max_locals != target->max_locals()) {
199 *ctx = ErrorContext::locals_size_mismatch(
200 _offset, (StackMapFrame*)this, (StackMapFrame*)target);
201 return false;
202 }
203 if (_stack_size != target->stack_size()) {
204 *ctx = ErrorContext::stack_size_mismatch(
205 _offset, (StackMapFrame*)this, (StackMapFrame*)target);
206 return false;
207 }
208 // Only need to compare type elements up to target->locals() or target->stack().
209 // The remaining type elements in this state can be ignored because they are
210 // assignable to bogus type.
211 int mismatch_loc;
212 mismatch_loc = is_assignable_to(
213 _locals, target->locals(), target->locals_size(), THREAD);
214 if (mismatch_loc != target->locals_size()) {
215 *ctx = ErrorContext::bad_type(target->offset(),
216 TypeOrigin::local(mismatch_loc, (StackMapFrame*)this),
217 TypeOrigin::sm_local(mismatch_loc, (StackMapFrame*)target));
218 return false;
219 }
220 mismatch_loc = is_assignable_to(_stack, target->stack(), _stack_size, THREAD);
221 if (mismatch_loc != _stack_size) {
222 *ctx = ErrorContext::bad_type(target->offset(),
223 TypeOrigin::stack(mismatch_loc, (StackMapFrame*)this),
224 TypeOrigin::sm_stack(mismatch_loc, (StackMapFrame*)target));
225 return false;
226 }
227
228 // Check that assert unset fields are compatible
229 bool compatible = verify_unset_fields_compatibility(target->assert_unset_fields());
230 if (!compatible) {
231 print_strict_fields(assert_unset_fields());
232 print_strict_fields(target->assert_unset_fields());
233 *ctx = ErrorContext::strict_fields_mismatch(target->offset(),
234 (StackMapFrame*)this, (StackMapFrame*)target);
235 return false;
236 }
237
238 if ((_flags | target->flags()) == target->flags()) {
239 return true;
240 } else {
241 *ctx = ErrorContext::bad_flags(target->offset(),
242 (StackMapFrame*)this, (StackMapFrame*)target);
243 return false;
244 }
245 }
246
247 VerificationType StackMapFrame::pop_stack_ex(VerificationType type, TRAPS) {
248 if (_stack_size <= 0) {
249 verifier()->verify_error(
250 ErrorContext::stack_underflow(_offset, this),
251 "Operand stack underflow");
252 return VerificationType::bogus_type();
253 }
254 VerificationType top = _stack[--_stack_size];
255 bool subtype = type.is_assignable_from(
256 top, verifier(), false, CHECK_(VerificationType::bogus_type()));
257 if (!subtype) {
258 verifier()->verify_error(
259 ErrorContext::bad_type(_offset, stack_top_ctx(),
260 TypeOrigin::implicit(type)),
261 "Bad type on operand stack");
262 return VerificationType::bogus_type();
263 }
264 return top;
265 }
266
267 VerificationType StackMapFrame::get_local(
268 int32_t index, VerificationType type, TRAPS) {
269 if (index >= _max_locals) {
270 verifier()->verify_error(
271 ErrorContext::bad_local_index(_offset, index),
272 "Local variable table overflow");
273 return VerificationType::bogus_type();
274 }
275 bool subtype = type.is_assignable_from(_locals[index],
276 verifier(), false, CHECK_(VerificationType::bogus_type()));
277 if (!subtype) {
278 verifier()->verify_error(
279 ErrorContext::bad_type(_offset,
280 TypeOrigin::local(index, this),
281 TypeOrigin::implicit(type)),
282 "Bad local variable type");
283 return VerificationType::bogus_type();
284 }
285 if(index >= _locals_size) { _locals_size = index + 1; }
286 return _locals[index];
287 }
288
289 void StackMapFrame::get_local_2(
290 int32_t index, VerificationType type1, VerificationType type2, TRAPS) {
291 assert(type1.is_long() || type1.is_double(), "must be long/double");
292 assert(type2.is_long2() || type2.is_double2(), "must be long/double_2");
293 if (index >= _locals_size - 1) {
294 verifier()->verify_error(
295 ErrorContext::bad_local_index(_offset, index),
296 "get long/double overflows locals");
297 return;
298 }
299 bool subtype = type1.is_assignable_from(_locals[index], verifier(), false, CHECK);
300 if (!subtype) {
301 verifier()->verify_error(
302 ErrorContext::bad_type(_offset,
303 TypeOrigin::local(index, this), TypeOrigin::implicit(type1)),
304 "Bad local variable type");
305 } else {
306 subtype = type2.is_assignable_from(_locals[index + 1], verifier(), false, CHECK);
307 if (!subtype) {
308 /* Unreachable? All local store routines convert a split long or double
309 * into a TOP during the store. So we should never end up seeing an
310 * orphaned half. */
311 verifier()->verify_error(
312 ErrorContext::bad_type(_offset,
313 TypeOrigin::local(index + 1, this), TypeOrigin::implicit(type2)),
314 "Bad local variable type");
315 }
316 }
317 }
318
319 void StackMapFrame::set_local(int32_t index, VerificationType type, TRAPS) {
320 assert(!type.is_check(), "Must be a real type");
321 if (index >= _max_locals) {
322 verifier()->verify_error(
323 ErrorContext::bad_local_index(_offset, index),
324 "Local variable table overflow");
325 return;
326 }
327 // If type at index is double or long, set the next location to be unusable
328 if (_locals[index].is_double() || _locals[index].is_long()) {
329 assert((index + 1) < _locals_size, "Local variable table overflow");
330 _locals[index + 1] = VerificationType::bogus_type();
331 }
332 // If type at index is double_2 or long_2, set the previous location to be unusable
333 if (_locals[index].is_double2() || _locals[index].is_long2()) {
334 assert(index >= 1, "Local variable table underflow");
335 _locals[index - 1] = VerificationType::bogus_type();
336 }
337 _locals[index] = type;
338 if (index >= _locals_size) {
339 #ifdef ASSERT
340 for (int i=_locals_size; i<index; i++) {
341 assert(_locals[i] == VerificationType::bogus_type(),
342 "holes must be bogus type");
343 }
344 #endif
345 _locals_size = index + 1;
346 }
347 }
348
349 void StackMapFrame::set_local_2(
350 int32_t index, VerificationType type1, VerificationType type2, TRAPS) {
351 assert(type1.is_long() || type1.is_double(), "must be long/double");
352 assert(type2.is_long2() || type2.is_double2(), "must be long/double_2");
353 if (index >= _max_locals - 1) {
354 verifier()->verify_error(
355 ErrorContext::bad_local_index(_offset, index),
356 "Local variable table overflow");
357 return;
358 }
359 // If type at index+1 is double or long, set the next location to be unusable
360 if (_locals[index+1].is_double() || _locals[index+1].is_long()) {
361 assert((index + 2) < _locals_size, "Local variable table overflow");
362 _locals[index + 2] = VerificationType::bogus_type();
363 }
364 // If type at index is double_2 or long_2, set the previous location to be unusable
365 if (_locals[index].is_double2() || _locals[index].is_long2()) {
366 assert(index >= 1, "Local variable table underflow");
367 _locals[index - 1] = VerificationType::bogus_type();
368 }
369 _locals[index] = type1;
370 _locals[index+1] = type2;
371 if (index >= _locals_size - 1) {
372 #ifdef ASSERT
373 for (int i=_locals_size; i<index; i++) {
374 assert(_locals[i] == VerificationType::bogus_type(),
375 "holes must be bogus type");
376 }
377 #endif
378 _locals_size = index + 2;
379 }
380 }
381
382 TypeOrigin StackMapFrame::stack_top_ctx() {
383 return TypeOrigin::stack(_stack_size, this);
384 }
385
386 void StackMapFrame::print_on(outputStream* str) const {
387 str->indent().print_cr("bci: @%d", _offset);
388 str->indent().print_cr("flags: {%s }",
389 flag_this_uninit() ? " flagThisUninit" : "");
390 str->indent().print("locals: {");
391 for (int32_t i = 0; i < _locals_size; ++i) {
392 str->print(" ");
393 _locals[i].print_on(str);
394 if (i != _locals_size - 1) {
395 str->print(",");
396 }
397 }
398 str->print_cr(" }");
399 str->indent().print("stack: {");
400 for (int32_t j = 0; j < _stack_size; ++j) {
401 str->print(" ");
402 _stack[j].print_on(str);
403 if (j != _stack_size - 1) {
404 str->print(",");
405 }
406 }
407 str->print_cr(" }");
408 }