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757bf1df | 1 | /* A state machine for detecting misuses of the malloc/free API. |
a945c346 | 2 | Copyright (C) 2019-2024 Free Software Foundation, Inc. |
757bf1df DM |
3 | Contributed by David Malcolm <dmalcolm@redhat.com>. |
4 | ||
5 | This file is part of GCC. | |
6 | ||
7 | GCC is free software; you can redistribute it and/or modify it | |
8 | under the terms of the GNU General Public License as published by | |
9 | the Free Software Foundation; either version 3, or (at your option) | |
10 | any later version. | |
11 | ||
12 | GCC is distributed in the hope that it will be useful, but | |
13 | WITHOUT ANY WARRANTY; without even the implied warranty of | |
14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
15 | General Public License for more details. | |
16 | ||
17 | You should have received a copy of the GNU General Public License | |
18 | along with GCC; see the file COPYING3. If not see | |
19 | <http://www.gnu.org/licenses/>. */ | |
20 | ||
21 | #include "config.h" | |
6341f14e | 22 | #define INCLUDE_MEMORY |
757bf1df DM |
23 | #include "system.h" |
24 | #include "coretypes.h" | |
6341f14e | 25 | #include "make-unique.h" |
757bf1df DM |
26 | #include "tree.h" |
27 | #include "function.h" | |
28 | #include "basic-block.h" | |
29 | #include "gimple.h" | |
30 | #include "options.h" | |
31 | #include "bitmap.h" | |
a242f696 | 32 | #include "diagnostic-core.h" |
757bf1df | 33 | #include "diagnostic-path.h" |
757bf1df DM |
34 | #include "analyzer/analyzer.h" |
35 | #include "diagnostic-event-id.h" | |
36 | #include "analyzer/analyzer-logging.h" | |
37 | #include "analyzer/sm.h" | |
38 | #include "analyzer/pending-diagnostic.h" | |
808f4dfe DM |
39 | #include "analyzer/call-string.h" |
40 | #include "analyzer/program-point.h" | |
41 | #include "analyzer/store.h" | |
42 | #include "analyzer/region-model.h" | |
861c917a | 43 | #include "analyzer/call-details.h" |
c7e276b8 DM |
44 | #include "stringpool.h" |
45 | #include "attribs.h" | |
cd323d97 | 46 | #include "analyzer/function-set.h" |
eafa9d96 | 47 | #include "analyzer/program-state.h" |
0d6f7b1d DM |
48 | #include "analyzer/checker-event.h" |
49 | #include "analyzer/exploded-graph.h" | |
5743e189 | 50 | #include "analyzer/inlining-iterator.h" |
757bf1df DM |
51 | |
52 | #if ENABLE_ANALYZER | |
53 | ||
75038aa6 DM |
54 | namespace ana { |
55 | ||
757bf1df DM |
56 | namespace { |
57 | ||
c7e276b8 DM |
58 | /* This state machine and its various support classes track allocations |
59 | and deallocations. | |
60 | ||
61 | It has a few standard allocation/deallocation pairs (e.g. new/delete), | |
62 | and also supports user-defined ones via | |
63 | __attribute__ ((malloc(DEALLOCATOR))). | |
64 | ||
65 | There can be more than one valid deallocator for a given allocator, | |
66 | for example: | |
67 | __attribute__ ((malloc (fclose))) | |
68 | __attribute__ ((malloc (freopen, 3))) | |
69 | FILE* fopen (const char*, const char*); | |
70 | A deallocator_set represents a particular set of valid deallocators. | |
71 | ||
72 | We track the expected deallocator_set for a value, but not the allocation | |
73 | function - there could be more than one allocator per deallocator_set. | |
74 | For example, there could be dozens of allocators for "free" beyond just | |
75 | malloc e.g. calloc, xstrdup, etc. We don't want to explode the number | |
76 | of states by tracking individual allocators in the exploded graph; | |
77 | we merely want to track "this value expects to have 'free' called on it". | |
78 | Perhaps we can reconstruct which allocator was used later, when emitting | |
79 | the path, if it's necessary for precision of wording of diagnostics. */ | |
80 | ||
81 | class deallocator; | |
82 | class deallocator_set; | |
1690a839 DM |
83 | class malloc_state_machine; |
84 | ||
85 | /* An enum for discriminating between different kinds of allocation_state. */ | |
86 | ||
87 | enum resource_state | |
88 | { | |
c7e276b8 | 89 | /* States that are independent of allocator/deallocator. */ |
1690a839 DM |
90 | |
91 | /* The start state. */ | |
92 | RS_START, | |
93 | ||
5c6546ca DM |
94 | /* State for a pointer that's been unconditionally dereferenced. */ |
95 | RS_ASSUMED_NON_NULL, | |
96 | ||
1690a839 DM |
97 | /* State for a pointer that's known to be NULL. */ |
98 | RS_NULL, | |
99 | ||
100 | /* State for a pointer that's known to not be on the heap (e.g. to a local | |
101 | or global). */ | |
102 | RS_NON_HEAP, | |
103 | ||
104 | /* Stop state, for pointers we don't want to track any more. */ | |
105 | RS_STOP, | |
106 | ||
c7e276b8 | 107 | /* States that relate to a specific deallocator_set. */ |
1690a839 | 108 | |
c7e276b8 | 109 | /* State for a pointer returned from an allocator that hasn't |
1690a839 DM |
110 | been checked for NULL. |
111 | It could be a pointer to heap-allocated memory, or could be NULL. */ | |
112 | RS_UNCHECKED, | |
113 | ||
c7e276b8 | 114 | /* State for a pointer returned from an allocator, |
1690a839 DM |
115 | known to be non-NULL. */ |
116 | RS_NONNULL, | |
117 | ||
c7e276b8 | 118 | /* State for a pointer passed to a deallocator. */ |
1690a839 DM |
119 | RS_FREED |
120 | }; | |
121 | ||
c7e276b8 DM |
122 | /* Custom state subclass, which can optionally refer to an a |
123 | deallocator_set. */ | |
1690a839 DM |
124 | |
125 | struct allocation_state : public state_machine::state | |
126 | { | |
127 | allocation_state (const char *name, unsigned id, | |
c7e276b8 DM |
128 | enum resource_state rs, |
129 | const deallocator_set *deallocators, | |
130 | const deallocator *deallocator) | |
131 | : state (name, id), m_rs (rs), | |
132 | m_deallocators (deallocators), | |
133 | m_deallocator (deallocator) | |
1690a839 DM |
134 | {} |
135 | ||
5c6546ca | 136 | void dump_to_pp (pretty_printer *pp) const override; |
1690a839 DM |
137 | |
138 | const allocation_state *get_nonnull () const; | |
139 | ||
140 | enum resource_state m_rs; | |
c7e276b8 DM |
141 | const deallocator_set *m_deallocators; |
142 | const deallocator *m_deallocator; | |
1690a839 DM |
143 | }; |
144 | ||
5c6546ca DM |
145 | /* Custom state subclass, for the "assumed-non-null" state |
146 | where the assumption happens in a particular frame. */ | |
147 | ||
148 | struct assumed_non_null_state : public allocation_state | |
149 | { | |
150 | assumed_non_null_state (const char *name, unsigned id, | |
151 | const frame_region *frame) | |
152 | : allocation_state (name, id, RS_ASSUMED_NON_NULL, | |
153 | NULL, NULL), | |
154 | m_frame (frame) | |
155 | { | |
156 | gcc_assert (m_frame); | |
157 | } | |
158 | ||
159 | void dump_to_pp (pretty_printer *pp) const final override; | |
160 | ||
161 | const frame_region *m_frame; | |
162 | }; | |
163 | ||
1690a839 DM |
164 | /* An enum for choosing which wording to use in various diagnostics |
165 | when describing deallocations. */ | |
166 | ||
167 | enum wording | |
168 | { | |
169 | WORDING_FREED, | |
c7e276b8 | 170 | WORDING_DELETED, |
a6baafca DM |
171 | WORDING_DEALLOCATED, |
172 | WORDING_REALLOCATED | |
1690a839 DM |
173 | }; |
174 | ||
c7e276b8 DM |
175 | /* Base class representing a deallocation function, |
176 | either a built-in one we know about, or one exposed via | |
177 | __attribute__((malloc(DEALLOCATOR))). */ | |
1690a839 | 178 | |
c7e276b8 | 179 | struct deallocator |
1690a839 | 180 | { |
c7e276b8 DM |
181 | hashval_t hash () const; |
182 | void dump_to_pp (pretty_printer *pp) const; | |
183 | static int cmp (const deallocator *a, const deallocator *b); | |
184 | static int cmp_ptr_ptr (const void *, const void *); | |
1690a839 | 185 | |
c7e276b8 | 186 | /* Name to use in diagnostics. */ |
1690a839 DM |
187 | const char *m_name; |
188 | ||
c7e276b8 DM |
189 | /* Which wording to use in diagnostics. */ |
190 | enum wording m_wording; | |
191 | ||
192 | /* State for a value passed to one of the deallocators. */ | |
193 | state_machine::state_t m_freed; | |
194 | ||
195 | protected: | |
196 | deallocator (malloc_state_machine *sm, | |
197 | const char *name, | |
198 | enum wording wording); | |
199 | }; | |
200 | ||
201 | /* Subclass representing a predefined deallocator. | |
202 | e.g. "delete []", without needing a specific FUNCTION_DECL | |
203 | ahead of time. */ | |
204 | ||
205 | struct standard_deallocator : public deallocator | |
206 | { | |
207 | standard_deallocator (malloc_state_machine *sm, | |
208 | const char *name, | |
209 | enum wording wording); | |
210 | }; | |
211 | ||
212 | /* Subclass representing a user-defined deallocator | |
213 | via __attribute__((malloc(DEALLOCATOR))) given | |
214 | a specific FUNCTION_DECL. */ | |
215 | ||
216 | struct custom_deallocator : public deallocator | |
217 | { | |
218 | custom_deallocator (malloc_state_machine *sm, | |
219 | tree deallocator_fndecl, | |
220 | enum wording wording) | |
221 | : deallocator (sm, IDENTIFIER_POINTER (DECL_NAME (deallocator_fndecl)), | |
222 | wording) | |
223 | { | |
224 | } | |
225 | }; | |
226 | ||
227 | /* Base class representing a set of possible deallocators. | |
228 | Often this will be just a single deallocator, but some | |
229 | allocators have multiple valid deallocators (e.g. the result of | |
230 | "fopen" can be closed by either "fclose" or "freopen"). */ | |
231 | ||
232 | struct deallocator_set | |
233 | { | |
234 | deallocator_set (malloc_state_machine *sm, | |
235 | enum wording wording); | |
236 | virtual ~deallocator_set () {} | |
237 | ||
238 | virtual bool contains_p (const deallocator *d) const = 0; | |
239 | virtual const deallocator *maybe_get_single () const = 0; | |
240 | virtual void dump_to_pp (pretty_printer *pp) const = 0; | |
241 | void dump () const; | |
1690a839 DM |
242 | |
243 | /* Which wording to use in diagnostics. */ | |
244 | enum wording m_wording; | |
245 | ||
c7e276b8 | 246 | /* Pointers to states. |
1690a839 DM |
247 | These states are owned by the state_machine base class. */ |
248 | ||
c7e276b8 | 249 | /* State for an unchecked result from an allocator using this set. */ |
1690a839 DM |
250 | state_machine::state_t m_unchecked; |
251 | ||
c7e276b8 | 252 | /* State for a known non-NULL result from such an allocator. */ |
1690a839 | 253 | state_machine::state_t m_nonnull; |
c7e276b8 | 254 | }; |
1690a839 | 255 | |
c7e276b8 DM |
256 | /* Subclass of deallocator_set representing a set of deallocators |
257 | defined by one or more __attribute__((malloc(DEALLOCATOR))). */ | |
258 | ||
259 | struct custom_deallocator_set : public deallocator_set | |
260 | { | |
261 | typedef const auto_vec <const deallocator *> *key_t; | |
262 | ||
263 | custom_deallocator_set (malloc_state_machine *sm, | |
264 | const auto_vec <const deallocator *> *vec, | |
265 | //const char *name, | |
266 | //const char *dealloc_funcname, | |
267 | //unsigned arg_idx, | |
268 | enum wording wording); | |
269 | ||
ff171cb1 DM |
270 | bool contains_p (const deallocator *d) const final override; |
271 | const deallocator *maybe_get_single () const final override; | |
272 | void dump_to_pp (pretty_printer *pp) const final override; | |
c7e276b8 DM |
273 | |
274 | auto_vec <const deallocator *> m_deallocator_vec; | |
275 | }; | |
276 | ||
277 | /* Subclass of deallocator_set representing a set of deallocators | |
278 | with a single standard_deallocator, e.g. "delete []". */ | |
279 | ||
280 | struct standard_deallocator_set : public deallocator_set | |
281 | { | |
282 | standard_deallocator_set (malloc_state_machine *sm, | |
283 | const char *name, | |
284 | enum wording wording); | |
285 | ||
ff171cb1 DM |
286 | bool contains_p (const deallocator *d) const final override; |
287 | const deallocator *maybe_get_single () const final override; | |
288 | void dump_to_pp (pretty_printer *pp) const final override; | |
c7e276b8 DM |
289 | |
290 | standard_deallocator m_deallocator; | |
291 | }; | |
292 | ||
293 | /* Traits class for ensuring uniqueness of deallocator_sets within | |
294 | malloc_state_machine. */ | |
295 | ||
296 | struct deallocator_set_map_traits | |
297 | { | |
298 | typedef custom_deallocator_set::key_t key_type; | |
299 | typedef custom_deallocator_set *value_type; | |
300 | typedef custom_deallocator_set *compare_type; | |
301 | ||
302 | static inline hashval_t hash (const key_type &k) | |
303 | { | |
304 | gcc_assert (k != NULL); | |
305 | gcc_assert (k != reinterpret_cast<key_type> (1)); | |
306 | ||
307 | hashval_t result = 0; | |
308 | unsigned i; | |
309 | const deallocator *d; | |
310 | FOR_EACH_VEC_ELT (*k, i, d) | |
311 | result ^= d->hash (); | |
312 | return result; | |
313 | } | |
314 | static inline bool equal_keys (const key_type &k1, const key_type &k2) | |
315 | { | |
316 | if (k1->length () != k2->length ()) | |
317 | return false; | |
318 | ||
319 | for (unsigned i = 0; i < k1->length (); i++) | |
320 | if ((*k1)[i] != (*k2)[i]) | |
321 | return false; | |
322 | ||
323 | return true; | |
324 | } | |
325 | template <typename T> | |
326 | static inline void remove (T &) | |
327 | { | |
328 | /* empty; the nodes are handled elsewhere. */ | |
329 | } | |
330 | template <typename T> | |
331 | static inline void mark_deleted (T &entry) | |
332 | { | |
333 | entry.m_key = reinterpret_cast<key_type> (1); | |
334 | } | |
335 | template <typename T> | |
336 | static inline void mark_empty (T &entry) | |
337 | { | |
338 | entry.m_key = NULL; | |
339 | } | |
340 | template <typename T> | |
341 | static inline bool is_deleted (const T &entry) | |
342 | { | |
343 | return entry.m_key == reinterpret_cast<key_type> (1); | |
344 | } | |
345 | template <typename T> | |
346 | static inline bool is_empty (const T &entry) | |
347 | { | |
348 | return entry.m_key == NULL; | |
349 | } | |
350 | static const bool empty_zero_p = false; | |
1690a839 DM |
351 | }; |
352 | ||
757bf1df DM |
353 | /* A state machine for detecting misuses of the malloc/free API. |
354 | ||
355 | See sm-malloc.dot for an overview (keep this in-sync with that file). */ | |
356 | ||
357 | class malloc_state_machine : public state_machine | |
358 | { | |
359 | public: | |
1690a839 DM |
360 | typedef allocation_state custom_data_t; |
361 | ||
757bf1df | 362 | malloc_state_machine (logger *logger); |
c7e276b8 | 363 | ~malloc_state_machine (); |
757bf1df | 364 | |
1690a839 | 365 | state_t |
c7e276b8 DM |
366 | add_state (const char *name, enum resource_state rs, |
367 | const deallocator_set *deallocators, | |
368 | const deallocator *deallocator); | |
1690a839 | 369 | |
ff171cb1 | 370 | bool inherited_state_p () const final override { return false; } |
757bf1df | 371 | |
808f4dfe | 372 | state_machine::state_t |
ff171cb1 | 373 | get_default_state (const svalue *sval) const final override |
808f4dfe DM |
374 | { |
375 | if (tree cst = sval->maybe_get_constant ()) | |
376 | { | |
377 | if (zerop (cst)) | |
378 | return m_null; | |
379 | } | |
380 | if (const region_svalue *ptr = sval->dyn_cast_region_svalue ()) | |
381 | { | |
382 | const region *reg = ptr->get_pointee (); | |
a61aaee6 DM |
383 | switch (reg->get_memory_space ()) |
384 | { | |
385 | default: | |
386 | break; | |
387 | case MEMSPACE_CODE: | |
388 | case MEMSPACE_GLOBALS: | |
389 | case MEMSPACE_STACK: | |
390 | case MEMSPACE_READONLY_DATA: | |
391 | return m_non_heap; | |
392 | } | |
808f4dfe DM |
393 | } |
394 | return m_start; | |
395 | } | |
396 | ||
757bf1df DM |
397 | bool on_stmt (sm_context *sm_ctxt, |
398 | const supernode *node, | |
ff171cb1 | 399 | const gimple *stmt) const final override; |
757bf1df | 400 | |
8525d1f5 DM |
401 | void on_phi (sm_context *sm_ctxt, |
402 | const supernode *node, | |
403 | const gphi *phi, | |
ff171cb1 | 404 | tree rhs) const final override; |
8525d1f5 | 405 | |
757bf1df DM |
406 | void on_condition (sm_context *sm_ctxt, |
407 | const supernode *node, | |
408 | const gimple *stmt, | |
48e8a7a6 | 409 | const svalue *lhs, |
757bf1df | 410 | enum tree_code op, |
ff171cb1 | 411 | const svalue *rhs) const final override; |
757bf1df | 412 | |
5c6546ca DM |
413 | void on_pop_frame (sm_state_map *smap, |
414 | const frame_region *) const final override; | |
415 | ||
ff171cb1 | 416 | bool can_purge_p (state_t s) const final override; |
6341f14e | 417 | std::unique_ptr<pending_diagnostic> on_leak (tree var) const final override; |
757bf1df | 418 | |
808f4dfe | 419 | bool reset_when_passed_to_unknown_fn_p (state_t s, |
ff171cb1 | 420 | bool is_mutable) const final override; |
808f4dfe | 421 | |
5c6546ca DM |
422 | state_t |
423 | maybe_get_merged_states_nonequal (state_t state_a, | |
424 | state_t state_b) const final override; | |
425 | ||
cd323d97 DM |
426 | static bool unaffected_by_call_p (tree fndecl); |
427 | ||
5c6546ca DM |
428 | void maybe_assume_non_null (sm_context *sm_ctxt, |
429 | tree ptr, | |
430 | const gimple *stmt) const; | |
431 | ||
eafa9d96 DM |
432 | void on_realloc_with_move (region_model *model, |
433 | sm_state_map *smap, | |
434 | const svalue *old_ptr_sval, | |
435 | const svalue *new_ptr_sval, | |
436 | const extrinsic_state &ext_state) const; | |
437 | ||
38c00edd EF |
438 | void transition_ptr_sval_non_null (region_model *model, |
439 | sm_state_map *smap, | |
440 | const svalue *new_ptr_sval, | |
441 | const extrinsic_state &ext_state) const; | |
442 | ||
c7e276b8 DM |
443 | standard_deallocator_set m_free; |
444 | standard_deallocator_set m_scalar_delete; | |
445 | standard_deallocator_set m_vector_delete; | |
1690a839 | 446 | |
a6baafca DM |
447 | standard_deallocator m_realloc; |
448 | ||
1690a839 | 449 | /* States that are independent of api. */ |
757bf1df | 450 | |
5c6546ca DM |
451 | /* States for a pointer that's been unconditionally dereferenced |
452 | in a particular stack frame. */ | |
453 | hash_map<const frame_region *, state_t> m_assumed_non_null; | |
454 | ||
757bf1df DM |
455 | /* State for a pointer that's known to be NULL. */ |
456 | state_t m_null; | |
457 | ||
757bf1df DM |
458 | /* State for a pointer that's known to not be on the heap (e.g. to a local |
459 | or global). */ | |
460 | state_t m_non_heap; // TODO: or should this be a different state machine? | |
461 | // or do we need child values etc? | |
462 | ||
463 | /* Stop state, for pointers we don't want to track any more. */ | |
464 | state_t m_stop; | |
8525d1f5 DM |
465 | |
466 | private: | |
c7e276b8 DM |
467 | const custom_deallocator_set * |
468 | get_or_create_custom_deallocator_set (tree allocator_fndecl); | |
469 | custom_deallocator_set * | |
470 | maybe_create_custom_deallocator_set (tree allocator_fndecl); | |
471 | const deallocator * | |
472 | get_or_create_deallocator (tree deallocator_fndecl); | |
473 | ||
5c6546ca DM |
474 | state_t |
475 | get_or_create_assumed_non_null_state_for_frame (const frame_region *frame); | |
476 | ||
477 | void | |
478 | maybe_complain_about_deref_before_check (sm_context *sm_ctxt, | |
479 | const supernode *node, | |
480 | const gimple *stmt, | |
481 | const assumed_non_null_state *, | |
482 | tree ptr) const; | |
483 | ||
1690a839 DM |
484 | void on_allocator_call (sm_context *sm_ctxt, |
485 | const gcall *call, | |
c7e276b8 DM |
486 | const deallocator_set *deallocators, |
487 | bool returns_nonnull = false) const; | |
a61aaee6 DM |
488 | void handle_free_of_non_heap (sm_context *sm_ctxt, |
489 | const supernode *node, | |
490 | const gcall *call, | |
491 | tree arg, | |
492 | const deallocator *d) const; | |
1690a839 DM |
493 | void on_deallocator_call (sm_context *sm_ctxt, |
494 | const supernode *node, | |
495 | const gcall *call, | |
c7e276b8 DM |
496 | const deallocator *d, |
497 | unsigned argno) const; | |
a6baafca DM |
498 | void on_realloc_call (sm_context *sm_ctxt, |
499 | const supernode *node, | |
500 | const gcall *call) const; | |
8525d1f5 | 501 | void on_zero_assignment (sm_context *sm_ctxt, |
8525d1f5 DM |
502 | const gimple *stmt, |
503 | tree lhs) const; | |
c7e276b8 DM |
504 | |
505 | /* A map for consolidating deallocators so that they are | |
506 | unique per deallocator FUNCTION_DECL. */ | |
507 | typedef hash_map<tree, deallocator *> deallocator_map_t; | |
508 | deallocator_map_t m_deallocator_map; | |
509 | ||
510 | /* Memoized lookups from FUNCTION_DECL to custom_deallocator_set *. */ | |
511 | typedef hash_map<tree, custom_deallocator_set *> deallocator_set_cache_t; | |
512 | deallocator_set_cache_t m_custom_deallocator_set_cache; | |
513 | ||
514 | /* A map for consolidating custom_deallocator_set instances. */ | |
515 | typedef hash_map<custom_deallocator_set::key_t, | |
516 | custom_deallocator_set *, | |
517 | deallocator_set_map_traits> custom_deallocator_set_map_t; | |
518 | custom_deallocator_set_map_t m_custom_deallocator_set_map; | |
519 | ||
520 | /* Record of dynamically-allocated objects, for cleanup. */ | |
521 | auto_vec <custom_deallocator_set *> m_dynamic_sets; | |
522 | auto_vec <custom_deallocator *> m_dynamic_deallocators; | |
757bf1df DM |
523 | }; |
524 | ||
c7e276b8 | 525 | /* struct deallocator. */ |
1690a839 | 526 | |
c7e276b8 DM |
527 | deallocator::deallocator (malloc_state_machine *sm, |
528 | const char *name, | |
529 | enum wording wording) | |
1690a839 | 530 | : m_name (name), |
1690a839 | 531 | m_wording (wording), |
c7e276b8 DM |
532 | m_freed (sm->add_state ("freed", RS_FREED, NULL, this)) |
533 | { | |
534 | } | |
535 | ||
536 | hashval_t | |
537 | deallocator::hash () const | |
538 | { | |
539 | return (hashval_t)m_freed->get_id (); | |
540 | } | |
541 | ||
542 | void | |
543 | deallocator::dump_to_pp (pretty_printer *pp) const | |
544 | { | |
545 | pp_printf (pp, "%qs", m_name); | |
546 | } | |
547 | ||
548 | int | |
549 | deallocator::cmp (const deallocator *a, const deallocator *b) | |
550 | { | |
551 | return (int)a->m_freed->get_id () - (int)b->m_freed->get_id (); | |
552 | } | |
553 | ||
554 | int | |
555 | deallocator::cmp_ptr_ptr (const void *a, const void *b) | |
556 | { | |
557 | return cmp (*(const deallocator * const *)a, | |
558 | *(const deallocator * const *)b); | |
559 | } | |
560 | ||
561 | ||
562 | /* struct standard_deallocator : public deallocator. */ | |
563 | ||
564 | standard_deallocator::standard_deallocator (malloc_state_machine *sm, | |
565 | const char *name, | |
566 | enum wording wording) | |
567 | : deallocator (sm, name, wording) | |
1690a839 DM |
568 | { |
569 | } | |
570 | ||
c7e276b8 DM |
571 | /* struct deallocator_set. */ |
572 | ||
573 | deallocator_set::deallocator_set (malloc_state_machine *sm, | |
574 | enum wording wording) | |
575 | : m_wording (wording), | |
576 | m_unchecked (sm->add_state ("unchecked", RS_UNCHECKED, this, NULL)), | |
577 | m_nonnull (sm->add_state ("nonnull", RS_NONNULL, this, NULL)) | |
578 | { | |
579 | } | |
580 | ||
581 | /* Dump a description of this deallocator_set to stderr. */ | |
582 | ||
583 | DEBUG_FUNCTION void | |
584 | deallocator_set::dump () const | |
585 | { | |
586 | pretty_printer pp; | |
587 | pp_show_color (&pp) = pp_show_color (global_dc->printer); | |
588 | pp.buffer->stream = stderr; | |
589 | dump_to_pp (&pp); | |
590 | pp_newline (&pp); | |
591 | pp_flush (&pp); | |
592 | } | |
593 | ||
594 | /* struct custom_deallocator_set : public deallocator_set. */ | |
595 | ||
596 | custom_deallocator_set:: | |
597 | custom_deallocator_set (malloc_state_machine *sm, | |
598 | const auto_vec <const deallocator *> *vec, | |
599 | enum wording wording) | |
600 | : deallocator_set (sm, wording), | |
601 | m_deallocator_vec (vec->length ()) | |
602 | { | |
603 | unsigned i; | |
604 | const deallocator *d; | |
605 | FOR_EACH_VEC_ELT (*vec, i, d) | |
606 | m_deallocator_vec.safe_push (d); | |
607 | } | |
608 | ||
609 | bool | |
610 | custom_deallocator_set::contains_p (const deallocator *d) const | |
611 | { | |
612 | unsigned i; | |
613 | const deallocator *cd; | |
614 | FOR_EACH_VEC_ELT (m_deallocator_vec, i, cd) | |
615 | if (cd == d) | |
616 | return true; | |
617 | return false; | |
618 | } | |
619 | ||
620 | const deallocator * | |
621 | custom_deallocator_set::maybe_get_single () const | |
622 | { | |
623 | if (m_deallocator_vec.length () == 1) | |
624 | return m_deallocator_vec[0]; | |
625 | return NULL; | |
626 | } | |
627 | ||
628 | void | |
629 | custom_deallocator_set::dump_to_pp (pretty_printer *pp) const | |
630 | { | |
631 | pp_character (pp, '{'); | |
632 | unsigned i; | |
633 | const deallocator *d; | |
634 | FOR_EACH_VEC_ELT (m_deallocator_vec, i, d) | |
635 | { | |
636 | if (i > 0) | |
637 | pp_string (pp, ", "); | |
638 | d->dump_to_pp (pp); | |
639 | } | |
640 | pp_character (pp, '}'); | |
641 | } | |
642 | ||
643 | /* struct standard_deallocator_set : public deallocator_set. */ | |
644 | ||
645 | standard_deallocator_set::standard_deallocator_set (malloc_state_machine *sm, | |
646 | const char *name, | |
647 | enum wording wording) | |
648 | : deallocator_set (sm, wording), | |
649 | m_deallocator (sm, name, wording) | |
650 | { | |
651 | } | |
652 | ||
653 | bool | |
654 | standard_deallocator_set::contains_p (const deallocator *d) const | |
655 | { | |
656 | return d == &m_deallocator; | |
657 | } | |
658 | ||
659 | const deallocator * | |
660 | standard_deallocator_set::maybe_get_single () const | |
661 | { | |
662 | return &m_deallocator; | |
663 | } | |
664 | ||
665 | void | |
666 | standard_deallocator_set::dump_to_pp (pretty_printer *pp) const | |
667 | { | |
668 | pp_character (pp, '{'); | |
669 | pp_string (pp, m_deallocator.m_name); | |
670 | pp_character (pp, '}'); | |
671 | } | |
672 | ||
1690a839 DM |
673 | /* Return STATE cast to the custom state subclass, or NULL for the start state. |
674 | Everything should be an allocation_state apart from the start state. */ | |
675 | ||
676 | static const allocation_state * | |
677 | dyn_cast_allocation_state (state_machine::state_t state) | |
678 | { | |
679 | if (state->get_id () == 0) | |
680 | return NULL; | |
681 | return static_cast <const allocation_state *> (state); | |
682 | } | |
683 | ||
684 | /* Return STATE cast to the custom state subclass, for a state that is | |
685 | already known to not be the start state . */ | |
686 | ||
687 | static const allocation_state * | |
688 | as_a_allocation_state (state_machine::state_t state) | |
689 | { | |
690 | gcc_assert (state->get_id () != 0); | |
691 | return static_cast <const allocation_state *> (state); | |
692 | } | |
693 | ||
694 | /* Get the resource_state for STATE. */ | |
695 | ||
696 | static enum resource_state | |
697 | get_rs (state_machine::state_t state) | |
698 | { | |
699 | if (const allocation_state *astate = dyn_cast_allocation_state (state)) | |
700 | return astate->m_rs; | |
701 | else | |
702 | return RS_START; | |
703 | } | |
704 | ||
c7e276b8 DM |
705 | /* Return true if STATE is the start state. */ |
706 | ||
707 | static bool | |
708 | start_p (state_machine::state_t state) | |
709 | { | |
710 | return get_rs (state) == RS_START; | |
711 | } | |
712 | ||
1690a839 DM |
713 | /* Return true if STATE is an unchecked result from an allocator. */ |
714 | ||
715 | static bool | |
716 | unchecked_p (state_machine::state_t state) | |
717 | { | |
718 | return get_rs (state) == RS_UNCHECKED; | |
719 | } | |
720 | ||
721 | /* Return true if STATE is a non-null result from an allocator. */ | |
722 | ||
723 | static bool | |
724 | nonnull_p (state_machine::state_t state) | |
725 | { | |
726 | return get_rs (state) == RS_NONNULL; | |
727 | } | |
728 | ||
729 | /* Return true if STATE is a value that has been passed to a deallocator. */ | |
730 | ||
731 | static bool | |
732 | freed_p (state_machine::state_t state) | |
733 | { | |
734 | return get_rs (state) == RS_FREED; | |
735 | } | |
736 | ||
5c6546ca DM |
737 | /* Return true if STATE is a value that has been assumed to be non-NULL. */ |
738 | ||
739 | static bool | |
740 | assumed_non_null_p (state_machine::state_t state) | |
741 | { | |
742 | return get_rs (state) == RS_ASSUMED_NON_NULL; | |
743 | } | |
744 | ||
757bf1df DM |
745 | /* Class for diagnostics relating to malloc_state_machine. */ |
746 | ||
747 | class malloc_diagnostic : public pending_diagnostic | |
748 | { | |
749 | public: | |
750 | malloc_diagnostic (const malloc_state_machine &sm, tree arg) | |
751 | : m_sm (sm), m_arg (arg) | |
752 | {} | |
753 | ||
ff171cb1 | 754 | bool subclass_equal_p (const pending_diagnostic &base_other) const override |
757bf1df | 755 | { |
14f9d7b9 | 756 | return same_tree_p (m_arg, ((const malloc_diagnostic &)base_other).m_arg); |
757bf1df DM |
757 | } |
758 | ||
759 | label_text describe_state_change (const evdesc::state_change &change) | |
ff171cb1 | 760 | override |
757bf1df | 761 | { |
10fc42a8 | 762 | if (change.m_old_state == m_sm.get_start_state () |
e7b26744 | 763 | && (unchecked_p (change.m_new_state) || nonnull_p (change.m_new_state))) |
757bf1df DM |
764 | // TODO: verify that it's the allocation stmt, not a copy |
765 | return label_text::borrow ("allocated here"); | |
1690a839 DM |
766 | if (unchecked_p (change.m_old_state) |
767 | && nonnull_p (change.m_new_state)) | |
808f4dfe DM |
768 | { |
769 | if (change.m_expr) | |
770 | return change.formatted_print ("assuming %qE is non-NULL", | |
771 | change.m_expr); | |
772 | else | |
773 | return change.formatted_print ("assuming %qs is non-NULL", | |
774 | "<unknown>"); | |
775 | } | |
757bf1df | 776 | if (change.m_new_state == m_sm.m_null) |
0993ad65 | 777 | { |
1690a839 | 778 | if (unchecked_p (change.m_old_state)) |
808f4dfe DM |
779 | { |
780 | if (change.m_expr) | |
781 | return change.formatted_print ("assuming %qE is NULL", | |
782 | change.m_expr); | |
783 | else | |
784 | return change.formatted_print ("assuming %qs is NULL", | |
785 | "<unknown>"); | |
786 | } | |
0993ad65 | 787 | else |
808f4dfe DM |
788 | { |
789 | if (change.m_expr) | |
790 | return change.formatted_print ("%qE is NULL", | |
791 | change.m_expr); | |
792 | else | |
793 | return change.formatted_print ("%qs is NULL", | |
794 | "<unknown>"); | |
795 | } | |
0993ad65 DM |
796 | } |
797 | ||
757bf1df DM |
798 | return label_text (); |
799 | } | |
800 | ||
6cf276dd DM |
801 | diagnostic_event::meaning |
802 | get_meaning_for_state_change (const evdesc::state_change &change) | |
803 | const final override | |
804 | { | |
805 | if (change.m_old_state == m_sm.get_start_state () | |
806 | && unchecked_p (change.m_new_state)) | |
807 | return diagnostic_event::meaning (diagnostic_event::VERB_acquire, | |
808 | diagnostic_event::NOUN_memory); | |
809 | if (freed_p (change.m_new_state)) | |
810 | return diagnostic_event::meaning (diagnostic_event::VERB_release, | |
811 | diagnostic_event::NOUN_memory); | |
812 | return diagnostic_event::meaning (); | |
813 | } | |
814 | ||
757bf1df DM |
815 | protected: |
816 | const malloc_state_machine &m_sm; | |
817 | tree m_arg; | |
818 | }; | |
819 | ||
1690a839 DM |
820 | /* Concrete subclass for reporting mismatching allocator/deallocator |
821 | diagnostics. */ | |
822 | ||
823 | class mismatching_deallocation : public malloc_diagnostic | |
824 | { | |
825 | public: | |
826 | mismatching_deallocation (const malloc_state_machine &sm, tree arg, | |
c7e276b8 DM |
827 | const deallocator_set *expected_deallocators, |
828 | const deallocator *actual_dealloc) | |
1690a839 | 829 | : malloc_diagnostic (sm, arg), |
c7e276b8 | 830 | m_expected_deallocators (expected_deallocators), |
1690a839 DM |
831 | m_actual_dealloc (actual_dealloc) |
832 | {} | |
833 | ||
ff171cb1 | 834 | const char *get_kind () const final override |
1690a839 DM |
835 | { |
836 | return "mismatching_deallocation"; | |
837 | } | |
838 | ||
ff171cb1 | 839 | int get_controlling_option () const final override |
7fd6e36e DM |
840 | { |
841 | return OPT_Wanalyzer_mismatching_deallocation; | |
842 | } | |
843 | ||
12b67d1e | 844 | bool emit (diagnostic_emission_context &ctxt) final override |
1690a839 DM |
845 | { |
846 | auto_diagnostic_group d; | |
12b67d1e | 847 | ctxt.add_cwe (762); /* CWE-762: Mismatched Memory Management Routines. */ |
c7e276b8 DM |
848 | if (const deallocator *expected_dealloc |
849 | = m_expected_deallocators->maybe_get_single ()) | |
12b67d1e DM |
850 | return ctxt.warn ("%qE should have been deallocated with %qs" |
851 | " but was deallocated with %qs", | |
852 | m_arg, expected_dealloc->m_name, | |
853 | m_actual_dealloc->m_name); | |
c7e276b8 | 854 | else |
12b67d1e DM |
855 | return ctxt.warn ("%qs called on %qE returned from a mismatched" |
856 | " allocation function", | |
857 | m_actual_dealloc->m_name, m_arg); | |
1690a839 DM |
858 | } |
859 | ||
860 | label_text describe_state_change (const evdesc::state_change &change) | |
ff171cb1 | 861 | final override |
1690a839 DM |
862 | { |
863 | if (unchecked_p (change.m_new_state)) | |
864 | { | |
865 | m_alloc_event = change.m_event_id; | |
c7e276b8 DM |
866 | if (const deallocator *expected_dealloc |
867 | = m_expected_deallocators->maybe_get_single ()) | |
868 | return change.formatted_print ("allocated here" | |
869 | " (expects deallocation with %qs)", | |
870 | expected_dealloc->m_name); | |
871 | else | |
872 | return change.formatted_print ("allocated here"); | |
1690a839 DM |
873 | } |
874 | return malloc_diagnostic::describe_state_change (change); | |
875 | } | |
876 | ||
ff171cb1 | 877 | label_text describe_final_event (const evdesc::final_event &ev) final override |
1690a839 DM |
878 | { |
879 | if (m_alloc_event.known_p ()) | |
c7e276b8 DM |
880 | { |
881 | if (const deallocator *expected_dealloc | |
882 | = m_expected_deallocators->maybe_get_single ()) | |
883 | return ev.formatted_print | |
884 | ("deallocated with %qs here;" | |
885 | " allocation at %@ expects deallocation with %qs", | |
886 | m_actual_dealloc->m_name, &m_alloc_event, | |
887 | expected_dealloc->m_name); | |
888 | else | |
889 | return ev.formatted_print | |
890 | ("deallocated with %qs here;" | |
891 | " allocated at %@", | |
892 | m_actual_dealloc->m_name, &m_alloc_event); | |
893 | } | |
1690a839 | 894 | return ev.formatted_print ("deallocated with %qs here", |
c7e276b8 | 895 | m_actual_dealloc->m_name); |
1690a839 DM |
896 | } |
897 | ||
898 | private: | |
899 | diagnostic_event_id_t m_alloc_event; | |
c7e276b8 DM |
900 | const deallocator_set *m_expected_deallocators; |
901 | const deallocator *m_actual_dealloc; | |
1690a839 DM |
902 | }; |
903 | ||
757bf1df DM |
904 | /* Concrete subclass for reporting double-free diagnostics. */ |
905 | ||
906 | class double_free : public malloc_diagnostic | |
907 | { | |
908 | public: | |
1690a839 DM |
909 | double_free (const malloc_state_machine &sm, tree arg, const char *funcname) |
910 | : malloc_diagnostic (sm, arg), m_funcname (funcname) | |
757bf1df DM |
911 | {} |
912 | ||
ff171cb1 | 913 | const char *get_kind () const final override { return "double_free"; } |
757bf1df | 914 | |
ff171cb1 | 915 | int get_controlling_option () const final override |
7fd6e36e DM |
916 | { |
917 | return OPT_Wanalyzer_double_free; | |
918 | } | |
919 | ||
12b67d1e | 920 | bool emit (diagnostic_emission_context &ctxt) final override |
757bf1df DM |
921 | { |
922 | auto_diagnostic_group d; | |
12b67d1e DM |
923 | ctxt.add_cwe (415); /* CWE-415: Double Free. */ |
924 | return ctxt.warn ("double-%qs of %qE", m_funcname, m_arg); | |
757bf1df DM |
925 | } |
926 | ||
927 | label_text describe_state_change (const evdesc::state_change &change) | |
ff171cb1 | 928 | final override |
757bf1df | 929 | { |
1690a839 | 930 | if (freed_p (change.m_new_state)) |
757bf1df DM |
931 | { |
932 | m_first_free_event = change.m_event_id; | |
1690a839 | 933 | return change.formatted_print ("first %qs here", m_funcname); |
757bf1df DM |
934 | } |
935 | return malloc_diagnostic::describe_state_change (change); | |
936 | } | |
937 | ||
938 | label_text describe_call_with_state (const evdesc::call_with_state &info) | |
ff171cb1 | 939 | final override |
757bf1df | 940 | { |
1690a839 | 941 | if (freed_p (info.m_state)) |
757bf1df DM |
942 | return info.formatted_print |
943 | ("passing freed pointer %qE in call to %qE from %qE", | |
944 | info.m_expr, info.m_callee_fndecl, info.m_caller_fndecl); | |
945 | return label_text (); | |
946 | } | |
947 | ||
ff171cb1 | 948 | label_text describe_final_event (const evdesc::final_event &ev) final override |
757bf1df DM |
949 | { |
950 | if (m_first_free_event.known_p ()) | |
951 | return ev.formatted_print ("second %qs here; first %qs was at %@", | |
1690a839 | 952 | m_funcname, m_funcname, |
757bf1df | 953 | &m_first_free_event); |
1690a839 | 954 | return ev.formatted_print ("second %qs here", m_funcname); |
757bf1df DM |
955 | } |
956 | ||
957 | private: | |
958 | diagnostic_event_id_t m_first_free_event; | |
1690a839 | 959 | const char *m_funcname; |
757bf1df DM |
960 | }; |
961 | ||
962 | /* Abstract subclass for describing possible bad uses of NULL. | |
963 | Responsible for describing the call that could return NULL. */ | |
964 | ||
965 | class possible_null : public malloc_diagnostic | |
966 | { | |
967 | public: | |
968 | possible_null (const malloc_state_machine &sm, tree arg) | |
969 | : malloc_diagnostic (sm, arg) | |
970 | {} | |
971 | ||
972 | label_text describe_state_change (const evdesc::state_change &change) | |
ff171cb1 | 973 | final override |
757bf1df | 974 | { |
10fc42a8 | 975 | if (change.m_old_state == m_sm.get_start_state () |
1690a839 | 976 | && unchecked_p (change.m_new_state)) |
757bf1df DM |
977 | { |
978 | m_origin_of_unchecked_event = change.m_event_id; | |
979 | return label_text::borrow ("this call could return NULL"); | |
980 | } | |
981 | return malloc_diagnostic::describe_state_change (change); | |
982 | } | |
983 | ||
984 | label_text describe_return_of_state (const evdesc::return_of_state &info) | |
ff171cb1 | 985 | final override |
757bf1df | 986 | { |
1690a839 | 987 | if (unchecked_p (info.m_state)) |
757bf1df DM |
988 | return info.formatted_print ("possible return of NULL to %qE from %qE", |
989 | info.m_caller_fndecl, info.m_callee_fndecl); | |
990 | return label_text (); | |
991 | } | |
992 | ||
993 | protected: | |
994 | diagnostic_event_id_t m_origin_of_unchecked_event; | |
995 | }; | |
996 | ||
997 | /* Concrete subclass for describing dereference of a possible NULL | |
998 | value. */ | |
999 | ||
1000 | class possible_null_deref : public possible_null | |
1001 | { | |
1002 | public: | |
1003 | possible_null_deref (const malloc_state_machine &sm, tree arg) | |
1004 | : possible_null (sm, arg) | |
1005 | {} | |
1006 | ||
ff171cb1 | 1007 | const char *get_kind () const final override { return "possible_null_deref"; } |
757bf1df | 1008 | |
ff171cb1 | 1009 | int get_controlling_option () const final override |
7fd6e36e DM |
1010 | { |
1011 | return OPT_Wanalyzer_possible_null_dereference; | |
1012 | } | |
1013 | ||
12b67d1e | 1014 | bool emit (diagnostic_emission_context &ctxt) final override |
757bf1df DM |
1015 | { |
1016 | /* CWE-690: Unchecked Return Value to NULL Pointer Dereference. */ | |
12b67d1e DM |
1017 | ctxt.add_cwe (690); |
1018 | return ctxt.warn ("dereference of possibly-NULL %qE", m_arg); | |
757bf1df DM |
1019 | } |
1020 | ||
ff171cb1 | 1021 | label_text describe_final_event (const evdesc::final_event &ev) final override |
757bf1df DM |
1022 | { |
1023 | if (m_origin_of_unchecked_event.known_p ()) | |
1024 | return ev.formatted_print ("%qE could be NULL: unchecked value from %@", | |
1025 | ev.m_expr, | |
1026 | &m_origin_of_unchecked_event); | |
1027 | else | |
1028 | return ev.formatted_print ("%qE could be NULL", ev.m_expr); | |
1029 | } | |
1030 | ||
1031 | }; | |
1032 | ||
2f7c50b7 DM |
1033 | /* Return true if FNDECL is a C++ method. */ |
1034 | ||
1035 | static bool | |
1036 | method_p (tree fndecl) | |
1037 | { | |
1038 | return TREE_CODE (TREE_TYPE (fndecl)) == METHOD_TYPE; | |
1039 | } | |
1040 | ||
1041 | /* Return a 1-based description of ARG_IDX (0-based) of FNDECL. | |
e53b6e56 | 1042 | Compare with %P in the C++ FE (implemented in cp/error.cc: parm_to_string |
2f7c50b7 DM |
1043 | as called from cp_printer). */ |
1044 | ||
1045 | static label_text | |
1046 | describe_argument_index (tree fndecl, int arg_idx) | |
1047 | { | |
1048 | if (method_p (fndecl)) | |
1049 | if (arg_idx == 0) | |
1050 | return label_text::borrow ("'this'"); | |
1051 | pretty_printer pp; | |
1052 | pp_printf (&pp, "%u", arg_idx + 1 - method_p (fndecl)); | |
1053 | return label_text::take (xstrdup (pp_formatted_text (&pp))); | |
1054 | } | |
1055 | ||
757bf1df DM |
1056 | /* Subroutine for use by possible_null_arg::emit and null_arg::emit. |
1057 | Issue a note informing that the pertinent argument must be non-NULL. */ | |
1058 | ||
1059 | static void | |
1060 | inform_nonnull_attribute (tree fndecl, int arg_idx) | |
1061 | { | |
2f7c50b7 | 1062 | label_text arg_desc = describe_argument_index (fndecl, arg_idx); |
757bf1df | 1063 | inform (DECL_SOURCE_LOCATION (fndecl), |
2f7c50b7 | 1064 | "argument %s of %qD must be non-null", |
f858fe7a | 1065 | arg_desc.get (), fndecl); |
757bf1df DM |
1066 | /* Ideally we would use the location of the parm and underline the |
1067 | attribute also - but we don't have the location_t values at this point | |
1068 | in the middle-end. | |
1069 | For reference, the C and C++ FEs have get_fndecl_argument_location. */ | |
1070 | } | |
1071 | ||
1072 | /* Concrete subclass for describing passing a possibly-NULL value to a | |
1073 | function marked with __attribute__((nonnull)). */ | |
1074 | ||
1075 | class possible_null_arg : public possible_null | |
1076 | { | |
1077 | public: | |
1078 | possible_null_arg (const malloc_state_machine &sm, tree arg, | |
1079 | tree fndecl, int arg_idx) | |
1080 | : possible_null (sm, arg), | |
1081 | m_fndecl (fndecl), m_arg_idx (arg_idx) | |
1082 | {} | |
1083 | ||
ff171cb1 | 1084 | const char *get_kind () const final override { return "possible_null_arg"; } |
757bf1df | 1085 | |
2ac1459f DM |
1086 | bool subclass_equal_p (const pending_diagnostic &base_other) |
1087 | const final override | |
757bf1df DM |
1088 | { |
1089 | const possible_null_arg &sub_other | |
1090 | = (const possible_null_arg &)base_other; | |
14f9d7b9 | 1091 | return (same_tree_p (m_arg, sub_other.m_arg) |
757bf1df DM |
1092 | && m_fndecl == sub_other.m_fndecl |
1093 | && m_arg_idx == sub_other.m_arg_idx); | |
1094 | } | |
1095 | ||
ff171cb1 | 1096 | int get_controlling_option () const final override |
7fd6e36e DM |
1097 | { |
1098 | return OPT_Wanalyzer_possible_null_argument; | |
1099 | } | |
757bf1df | 1100 | |
12b67d1e | 1101 | bool emit (diagnostic_emission_context &ctxt) final override |
757bf1df DM |
1102 | { |
1103 | /* CWE-690: Unchecked Return Value to NULL Pointer Dereference. */ | |
1104 | auto_diagnostic_group d; | |
12b67d1e | 1105 | ctxt.add_cwe (690); |
757bf1df | 1106 | bool warned |
12b67d1e DM |
1107 | = ctxt.warn ("use of possibly-NULL %qE where non-null expected", |
1108 | m_arg); | |
757bf1df DM |
1109 | if (warned) |
1110 | inform_nonnull_attribute (m_fndecl, m_arg_idx); | |
1111 | return warned; | |
1112 | } | |
1113 | ||
ff171cb1 | 1114 | label_text describe_final_event (const evdesc::final_event &ev) final override |
757bf1df | 1115 | { |
2f7c50b7 DM |
1116 | label_text arg_desc = describe_argument_index (m_fndecl, m_arg_idx); |
1117 | label_text result; | |
757bf1df | 1118 | if (m_origin_of_unchecked_event.known_p ()) |
2f7c50b7 DM |
1119 | result = ev.formatted_print ("argument %s (%qE) from %@ could be NULL" |
1120 | " where non-null expected", | |
f858fe7a | 1121 | arg_desc.get (), ev.m_expr, |
2f7c50b7 | 1122 | &m_origin_of_unchecked_event); |
757bf1df | 1123 | else |
2f7c50b7 DM |
1124 | result = ev.formatted_print ("argument %s (%qE) could be NULL" |
1125 | " where non-null expected", | |
f858fe7a | 1126 | arg_desc.get (), ev.m_expr); |
2f7c50b7 | 1127 | return result; |
757bf1df DM |
1128 | } |
1129 | ||
1130 | private: | |
1131 | tree m_fndecl; | |
1132 | int m_arg_idx; | |
1133 | }; | |
1134 | ||
1135 | /* Concrete subclass for describing a dereference of a NULL value. */ | |
1136 | ||
1137 | class null_deref : public malloc_diagnostic | |
1138 | { | |
1139 | public: | |
1140 | null_deref (const malloc_state_machine &sm, tree arg) | |
1141 | : malloc_diagnostic (sm, arg) {} | |
1142 | ||
ff171cb1 | 1143 | const char *get_kind () const final override { return "null_deref"; } |
757bf1df | 1144 | |
ff171cb1 | 1145 | int get_controlling_option () const final override |
7fd6e36e DM |
1146 | { |
1147 | return OPT_Wanalyzer_null_dereference; | |
1148 | } | |
1149 | ||
8f636915 DM |
1150 | bool terminate_path_p () const final override { return true; } |
1151 | ||
12b67d1e | 1152 | bool emit (diagnostic_emission_context &ctxt) final override |
757bf1df | 1153 | { |
f3f312b5 | 1154 | /* CWE-476: NULL Pointer Dereference. */ |
12b67d1e DM |
1155 | ctxt.add_cwe (476); |
1156 | return ctxt.warn ("dereference of NULL %qE", m_arg); | |
757bf1df DM |
1157 | } |
1158 | ||
1159 | label_text describe_return_of_state (const evdesc::return_of_state &info) | |
ff171cb1 | 1160 | final override |
757bf1df DM |
1161 | { |
1162 | if (info.m_state == m_sm.m_null) | |
1163 | return info.formatted_print ("return of NULL to %qE from %qE", | |
1164 | info.m_caller_fndecl, info.m_callee_fndecl); | |
1165 | return label_text (); | |
1166 | } | |
1167 | ||
ff171cb1 | 1168 | label_text describe_final_event (const evdesc::final_event &ev) final override |
757bf1df DM |
1169 | { |
1170 | return ev.formatted_print ("dereference of NULL %qE", ev.m_expr); | |
1171 | } | |
e7b26744 | 1172 | |
1173 | /* Implementation of pending_diagnostic::supercedes_p for | |
1174 | null-deref. | |
1175 | ||
1176 | We want null-deref to supercede use-of-unitialized-value, | |
1177 | so that if we have these at the same stmt, we don't emit | |
1178 | a use-of-uninitialized, just the null-deref. */ | |
1179 | ||
1180 | bool supercedes_p (const pending_diagnostic &other) const final override | |
1181 | { | |
1182 | if (other.use_of_uninit_p ()) | |
1183 | return true; | |
1184 | ||
1185 | return false; | |
1186 | } | |
757bf1df DM |
1187 | }; |
1188 | ||
1189 | /* Concrete subclass for describing passing a NULL value to a | |
1190 | function marked with __attribute__((nonnull)). */ | |
1191 | ||
1192 | class null_arg : public malloc_diagnostic | |
1193 | { | |
1194 | public: | |
1195 | null_arg (const malloc_state_machine &sm, tree arg, | |
1196 | tree fndecl, int arg_idx) | |
1197 | : malloc_diagnostic (sm, arg), | |
1198 | m_fndecl (fndecl), m_arg_idx (arg_idx) | |
1199 | {} | |
1200 | ||
ff171cb1 | 1201 | const char *get_kind () const final override { return "null_arg"; } |
757bf1df | 1202 | |
2ac1459f DM |
1203 | bool subclass_equal_p (const pending_diagnostic &base_other) |
1204 | const final override | |
757bf1df DM |
1205 | { |
1206 | const null_arg &sub_other | |
1207 | = (const null_arg &)base_other; | |
14f9d7b9 | 1208 | return (same_tree_p (m_arg, sub_other.m_arg) |
757bf1df DM |
1209 | && m_fndecl == sub_other.m_fndecl |
1210 | && m_arg_idx == sub_other.m_arg_idx); | |
1211 | } | |
1212 | ||
ff171cb1 | 1213 | int get_controlling_option () const final override |
7fd6e36e DM |
1214 | { |
1215 | return OPT_Wanalyzer_null_argument; | |
1216 | } | |
1217 | ||
8f636915 DM |
1218 | bool terminate_path_p () const final override { return true; } |
1219 | ||
12b67d1e | 1220 | bool emit (diagnostic_emission_context &ctxt) final override |
757bf1df | 1221 | { |
f3f312b5 | 1222 | /* CWE-476: NULL Pointer Dereference. */ |
757bf1df | 1223 | auto_diagnostic_group d; |
12b67d1e | 1224 | ctxt.add_cwe (476); |
808f4dfe DM |
1225 | |
1226 | bool warned; | |
1227 | if (zerop (m_arg)) | |
12b67d1e | 1228 | warned = ctxt.warn ("use of NULL where non-null expected"); |
808f4dfe | 1229 | else |
12b67d1e DM |
1230 | warned = ctxt.warn ("use of NULL %qE where non-null expected", |
1231 | m_arg); | |
757bf1df DM |
1232 | if (warned) |
1233 | inform_nonnull_attribute (m_fndecl, m_arg_idx); | |
1234 | return warned; | |
1235 | } | |
1236 | ||
ff171cb1 | 1237 | label_text describe_final_event (const evdesc::final_event &ev) final override |
757bf1df | 1238 | { |
2f7c50b7 DM |
1239 | label_text arg_desc = describe_argument_index (m_fndecl, m_arg_idx); |
1240 | label_text result; | |
808f4dfe | 1241 | if (zerop (ev.m_expr)) |
2f7c50b7 | 1242 | result = ev.formatted_print ("argument %s NULL where non-null expected", |
f858fe7a | 1243 | arg_desc.get ()); |
808f4dfe | 1244 | else |
2f7c50b7 DM |
1245 | result = ev.formatted_print ("argument %s (%qE) NULL" |
1246 | " where non-null expected", | |
f858fe7a | 1247 | arg_desc.get (), ev.m_expr); |
2f7c50b7 | 1248 | return result; |
757bf1df DM |
1249 | } |
1250 | ||
1251 | private: | |
1252 | tree m_fndecl; | |
1253 | int m_arg_idx; | |
1254 | }; | |
1255 | ||
1256 | class use_after_free : public malloc_diagnostic | |
1257 | { | |
1258 | public: | |
1690a839 | 1259 | use_after_free (const malloc_state_machine &sm, tree arg, |
c7e276b8 DM |
1260 | const deallocator *deallocator) |
1261 | : malloc_diagnostic (sm, arg), | |
1262 | m_deallocator (deallocator) | |
1263 | { | |
1264 | gcc_assert (deallocator); | |
1265 | } | |
757bf1df | 1266 | |
ff171cb1 | 1267 | const char *get_kind () const final override { return "use_after_free"; } |
757bf1df | 1268 | |
ff171cb1 | 1269 | int get_controlling_option () const final override |
7fd6e36e DM |
1270 | { |
1271 | return OPT_Wanalyzer_use_after_free; | |
1272 | } | |
1273 | ||
12b67d1e | 1274 | bool emit (diagnostic_emission_context &ctxt) final override |
757bf1df DM |
1275 | { |
1276 | /* CWE-416: Use After Free. */ | |
12b67d1e DM |
1277 | ctxt.add_cwe (416); |
1278 | return ctxt.warn ("use after %<%s%> of %qE", | |
1279 | m_deallocator->m_name, m_arg); | |
757bf1df DM |
1280 | } |
1281 | ||
1282 | label_text describe_state_change (const evdesc::state_change &change) | |
ff171cb1 | 1283 | final override |
757bf1df | 1284 | { |
1690a839 | 1285 | if (freed_p (change.m_new_state)) |
757bf1df DM |
1286 | { |
1287 | m_free_event = change.m_event_id; | |
c7e276b8 | 1288 | switch (m_deallocator->m_wording) |
1690a839 DM |
1289 | { |
1290 | default: | |
a6baafca | 1291 | case WORDING_REALLOCATED: |
1690a839 DM |
1292 | gcc_unreachable (); |
1293 | case WORDING_FREED: | |
1294 | return label_text::borrow ("freed here"); | |
1295 | case WORDING_DELETED: | |
1296 | return label_text::borrow ("deleted here"); | |
c7e276b8 DM |
1297 | case WORDING_DEALLOCATED: |
1298 | return label_text::borrow ("deallocated here"); | |
1690a839 | 1299 | } |
757bf1df DM |
1300 | } |
1301 | return malloc_diagnostic::describe_state_change (change); | |
1302 | } | |
1303 | ||
ff171cb1 | 1304 | label_text describe_final_event (const evdesc::final_event &ev) final override |
757bf1df | 1305 | { |
c7e276b8 | 1306 | const char *funcname = m_deallocator->m_name; |
757bf1df | 1307 | if (m_free_event.known_p ()) |
c7e276b8 | 1308 | switch (m_deallocator->m_wording) |
1690a839 DM |
1309 | { |
1310 | default: | |
a6baafca | 1311 | case WORDING_REALLOCATED: |
1690a839 DM |
1312 | gcc_unreachable (); |
1313 | case WORDING_FREED: | |
1314 | return ev.formatted_print ("use after %<%s%> of %qE; freed at %@", | |
1315 | funcname, ev.m_expr, &m_free_event); | |
1316 | case WORDING_DELETED: | |
1317 | return ev.formatted_print ("use after %<%s%> of %qE; deleted at %@", | |
1318 | funcname, ev.m_expr, &m_free_event); | |
c7e276b8 DM |
1319 | case WORDING_DEALLOCATED: |
1320 | return ev.formatted_print ("use after %<%s%> of %qE;" | |
1321 | " deallocated at %@", | |
1322 | funcname, ev.m_expr, &m_free_event); | |
1690a839 | 1323 | } |
757bf1df | 1324 | else |
1690a839 DM |
1325 | return ev.formatted_print ("use after %<%s%> of %qE", |
1326 | funcname, ev.m_expr); | |
757bf1df DM |
1327 | } |
1328 | ||
33255ad3 DM |
1329 | /* Implementation of pending_diagnostic::supercedes_p for |
1330 | use_after_free. | |
1331 | ||
1332 | We want use-after-free to supercede use-of-unitialized-value, | |
1333 | so that if we have these at the same stmt, we don't emit | |
1334 | a use-of-uninitialized, just the use-after-free. | |
1335 | (this is because we fully purge information about freed | |
1336 | buffers when we free them to avoid state explosions, so | |
1337 | that if they are accessed after the free, it looks like | |
1338 | they are uninitialized). */ | |
1339 | ||
ff171cb1 | 1340 | bool supercedes_p (const pending_diagnostic &other) const final override |
33255ad3 DM |
1341 | { |
1342 | if (other.use_of_uninit_p ()) | |
1343 | return true; | |
1344 | ||
1345 | return false; | |
1346 | } | |
1347 | ||
757bf1df DM |
1348 | private: |
1349 | diagnostic_event_id_t m_free_event; | |
c7e276b8 | 1350 | const deallocator *m_deallocator; |
757bf1df DM |
1351 | }; |
1352 | ||
1353 | class malloc_leak : public malloc_diagnostic | |
1354 | { | |
1355 | public: | |
1356 | malloc_leak (const malloc_state_machine &sm, tree arg) | |
1357 | : malloc_diagnostic (sm, arg) {} | |
1358 | ||
ff171cb1 | 1359 | const char *get_kind () const final override { return "malloc_leak"; } |
757bf1df | 1360 | |
ff171cb1 | 1361 | int get_controlling_option () const final override |
7fd6e36e DM |
1362 | { |
1363 | return OPT_Wanalyzer_malloc_leak; | |
1364 | } | |
1365 | ||
12b67d1e | 1366 | bool emit (diagnostic_emission_context &ctxt) final override |
757bf1df | 1367 | { |
9c603380 | 1368 | /* "CWE-401: Missing Release of Memory after Effective Lifetime". */ |
12b67d1e | 1369 | ctxt.add_cwe (401); |
808f4dfe | 1370 | if (m_arg) |
12b67d1e | 1371 | return ctxt.warn ("leak of %qE", m_arg); |
808f4dfe | 1372 | else |
12b67d1e | 1373 | return ctxt.warn ("leak of %qs", "<unknown>"); |
757bf1df DM |
1374 | } |
1375 | ||
1376 | label_text describe_state_change (const evdesc::state_change &change) | |
ff171cb1 | 1377 | final override |
757bf1df | 1378 | { |
c7e276b8 DM |
1379 | if (unchecked_p (change.m_new_state) |
1380 | || (start_p (change.m_old_state) && nonnull_p (change.m_new_state))) | |
757bf1df | 1381 | { |
1690a839 | 1382 | m_alloc_event = change.m_event_id; |
757bf1df DM |
1383 | return label_text::borrow ("allocated here"); |
1384 | } | |
1385 | return malloc_diagnostic::describe_state_change (change); | |
1386 | } | |
1387 | ||
ff171cb1 | 1388 | label_text describe_final_event (const evdesc::final_event &ev) final override |
757bf1df | 1389 | { |
808f4dfe DM |
1390 | if (ev.m_expr) |
1391 | { | |
1690a839 | 1392 | if (m_alloc_event.known_p ()) |
808f4dfe | 1393 | return ev.formatted_print ("%qE leaks here; was allocated at %@", |
1690a839 | 1394 | ev.m_expr, &m_alloc_event); |
808f4dfe DM |
1395 | else |
1396 | return ev.formatted_print ("%qE leaks here", ev.m_expr); | |
1397 | } | |
757bf1df | 1398 | else |
808f4dfe | 1399 | { |
1690a839 | 1400 | if (m_alloc_event.known_p ()) |
808f4dfe | 1401 | return ev.formatted_print ("%qs leaks here; was allocated at %@", |
1690a839 | 1402 | "<unknown>", &m_alloc_event); |
808f4dfe DM |
1403 | else |
1404 | return ev.formatted_print ("%qs leaks here", "<unknown>"); | |
1405 | } | |
757bf1df DM |
1406 | } |
1407 | ||
1408 | private: | |
1690a839 | 1409 | diagnostic_event_id_t m_alloc_event; |
757bf1df DM |
1410 | }; |
1411 | ||
1412 | class free_of_non_heap : public malloc_diagnostic | |
1413 | { | |
1414 | public: | |
1690a839 | 1415 | free_of_non_heap (const malloc_state_machine &sm, tree arg, |
a61aaee6 | 1416 | const region *freed_reg, |
1690a839 | 1417 | const char *funcname) |
a61aaee6 | 1418 | : malloc_diagnostic (sm, arg), m_freed_reg (freed_reg), m_funcname (funcname) |
757bf1df DM |
1419 | { |
1420 | } | |
1421 | ||
ff171cb1 | 1422 | const char *get_kind () const final override { return "free_of_non_heap"; } |
757bf1df DM |
1423 | |
1424 | bool subclass_equal_p (const pending_diagnostic &base_other) const | |
ff171cb1 | 1425 | final override |
757bf1df DM |
1426 | { |
1427 | const free_of_non_heap &other = (const free_of_non_heap &)base_other; | |
a61aaee6 DM |
1428 | return (same_tree_p (m_arg, other.m_arg) |
1429 | && m_freed_reg == other.m_freed_reg); | |
757bf1df DM |
1430 | } |
1431 | ||
ff171cb1 | 1432 | int get_controlling_option () const final override |
7fd6e36e DM |
1433 | { |
1434 | return OPT_Wanalyzer_free_of_non_heap; | |
1435 | } | |
1436 | ||
12b67d1e | 1437 | bool emit (diagnostic_emission_context &ctxt) final override |
757bf1df DM |
1438 | { |
1439 | auto_diagnostic_group d; | |
12b67d1e | 1440 | ctxt.add_cwe (590); /* CWE-590: Free of Memory not on the Heap. */ |
a61aaee6 | 1441 | switch (get_memory_space ()) |
757bf1df DM |
1442 | { |
1443 | default: | |
a61aaee6 | 1444 | case MEMSPACE_HEAP: |
757bf1df | 1445 | gcc_unreachable (); |
a61aaee6 DM |
1446 | case MEMSPACE_UNKNOWN: |
1447 | case MEMSPACE_CODE: | |
1448 | case MEMSPACE_GLOBALS: | |
1449 | case MEMSPACE_READONLY_DATA: | |
12b67d1e DM |
1450 | return ctxt.warn ("%<%s%> of %qE which points to memory" |
1451 | " not on the heap", | |
1452 | m_funcname, m_arg); | |
757bf1df | 1453 | break; |
a61aaee6 | 1454 | case MEMSPACE_STACK: |
12b67d1e DM |
1455 | return ctxt.warn ("%<%s%> of %qE which points to memory" |
1456 | " on the stack", | |
1457 | m_funcname, m_arg); | |
757bf1df DM |
1458 | break; |
1459 | } | |
1460 | } | |
1461 | ||
a61aaee6 | 1462 | label_text describe_state_change (const evdesc::state_change &) |
ff171cb1 | 1463 | final override |
757bf1df | 1464 | { |
757bf1df DM |
1465 | return label_text::borrow ("pointer is from here"); |
1466 | } | |
1467 | ||
ff171cb1 | 1468 | label_text describe_final_event (const evdesc::final_event &ev) final override |
757bf1df | 1469 | { |
1690a839 | 1470 | return ev.formatted_print ("call to %qs here", m_funcname); |
757bf1df DM |
1471 | } |
1472 | ||
ff171cb1 | 1473 | void mark_interesting_stuff (interesting_t *interest) final override |
a61aaee6 DM |
1474 | { |
1475 | if (m_freed_reg) | |
1476 | interest->add_region_creation (m_freed_reg); | |
1477 | } | |
1478 | ||
757bf1df | 1479 | private: |
a61aaee6 | 1480 | enum memory_space get_memory_space () const |
757bf1df | 1481 | { |
a61aaee6 DM |
1482 | if (m_freed_reg) |
1483 | return m_freed_reg->get_memory_space (); | |
1484 | else | |
1485 | return MEMSPACE_UNKNOWN; | |
1486 | } | |
1487 | ||
1488 | const region *m_freed_reg; | |
1690a839 | 1489 | const char *m_funcname; |
757bf1df DM |
1490 | }; |
1491 | ||
5c6546ca DM |
1492 | /* Concrete pending_diagnostic subclass for -Wanalyzer-deref-before-check. */ |
1493 | ||
1494 | class deref_before_check : public malloc_diagnostic | |
1495 | { | |
1496 | public: | |
1497 | deref_before_check (const malloc_state_machine &sm, tree arg) | |
0d6f7b1d DM |
1498 | : malloc_diagnostic (sm, arg), |
1499 | m_deref_enode (NULL), | |
c4fd232f | 1500 | m_deref_expr (NULL), |
0d6f7b1d | 1501 | m_check_enode (NULL) |
c4fd232f DM |
1502 | { |
1503 | gcc_assert (arg); | |
1504 | } | |
5c6546ca DM |
1505 | |
1506 | const char *get_kind () const final override { return "deref_before_check"; } | |
1507 | ||
1508 | int get_controlling_option () const final override | |
1509 | { | |
1510 | return OPT_Wanalyzer_deref_before_check; | |
1511 | } | |
1512 | ||
12b67d1e | 1513 | bool emit (diagnostic_emission_context &ctxt) final override |
5c6546ca | 1514 | { |
0d6f7b1d DM |
1515 | /* Don't emit the warning if we can't show where the deref |
1516 | and the check occur. */ | |
1517 | if (!m_deref_enode) | |
1518 | return false; | |
1519 | if (!m_check_enode) | |
1520 | return false; | |
1521 | /* Only emit the warning for intraprocedural cases. */ | |
0c652ebb DM |
1522 | const program_point &deref_point = m_deref_enode->get_point (); |
1523 | const program_point &check_point = m_check_enode->get_point (); | |
1524 | ||
1525 | if (!program_point::effectively_intraprocedural_p (deref_point, | |
1526 | check_point)) | |
0d6f7b1d DM |
1527 | return false; |
1528 | ||
aa601e30 DM |
1529 | /* Reject the warning if the check occurs within a macro defintion. |
1530 | This avoids false positives for such code as: | |
1531 | ||
1532 | #define throw_error \ | |
1533 | do { \ | |
1534 | if (p) \ | |
1535 | cleanup (p); \ | |
1536 | return; \ | |
1537 | } while (0) | |
1538 | ||
1539 | if (p->idx >= n) | |
1540 | throw_error (); | |
1541 | ||
1542 | where the usage of "throw_error" implicitly adds a check | |
1543 | on 'p'. | |
1544 | ||
1545 | We do warn when the check is in a macro expansion if we can get | |
1546 | at the location of the condition and it is't part of the | |
1547 | definition, so that we warn for checks such as: | |
1548 | if (words[0][0] == '@') | |
1549 | return; | |
1550 | g_assert(words[0] != NULL); <--- here | |
1551 | Unfortunately we don't have locations for individual gimple | |
1552 | arguments, so in: | |
1553 | g_assert (ptr); | |
1554 | we merely have a gimple_cond | |
1555 | if (p_2(D) == 0B) | |
1556 | with no way of getting at the location of the condition separately | |
1557 | from that of the gimple_cond (where the "if" is within the macro | |
1558 | definition). We reject the warning for such cases. | |
1559 | ||
1560 | We do warn when the *deref* occurs in a macro, since this can be | |
1561 | a source of real bugs; see e.g. PR 77425. */ | |
1562 | location_t check_loc = m_check_enode->get_point ().get_location (); | |
1563 | if (linemap_location_from_macro_definition_p (line_table, check_loc)) | |
1564 | return false; | |
1565 | ||
9093f275 DM |
1566 | /* Reject warning if the check is in a loop header within a |
1567 | macro expansion. This rejects cases like: | |
1568 | | deref of x; | |
1569 | | [...snip...] | |
1570 | | FOR_EACH(x) { | |
1571 | | [...snip...] | |
1572 | | } | |
1573 | where the FOR_EACH macro tests for non-nullness of x, since | |
1574 | the user is hoping to encapsulate the details of iteration | |
1575 | in the macro, and the extra check on the first iteration | |
1576 | would just be noise if we reported it. */ | |
1577 | if (loop_header_p (m_check_enode->get_point ()) | |
1578 | && linemap_location_from_macro_expansion_p (line_table, check_loc)) | |
1579 | return false; | |
1580 | ||
c4fd232f DM |
1581 | /* Reject if m_deref_expr is sufficiently different from m_arg |
1582 | for cases where the dereference is spelled differently from | |
1583 | the check, which is probably two different ways to get the | |
1584 | same svalue, and thus not worth reporting. */ | |
1585 | if (!m_deref_expr) | |
1586 | return false; | |
1587 | if (!sufficiently_similar_p (m_deref_expr, m_arg)) | |
1588 | return false; | |
1589 | ||
0d6f7b1d DM |
1590 | /* Reject the warning if the deref's BB doesn't dominate that |
1591 | of the check, so that we don't warn e.g. for shared cleanup | |
1592 | code that checks a pointer for NULL, when that code is sometimes | |
1593 | used before a deref and sometimes after. | |
1594 | Using the dominance code requires setting cfun. */ | |
1595 | auto_cfun sentinel (m_deref_enode->get_function ()); | |
1596 | calculate_dominance_info (CDI_DOMINATORS); | |
1597 | if (!dominated_by_p (CDI_DOMINATORS, | |
1598 | m_check_enode->get_supernode ()->m_bb, | |
1599 | m_deref_enode->get_supernode ()->m_bb)) | |
1600 | return false; | |
1601 | ||
12b67d1e DM |
1602 | return ctxt.warn ("check of %qE for NULL after already" |
1603 | " dereferencing it", | |
1604 | m_arg); | |
5c6546ca DM |
1605 | } |
1606 | ||
1607 | label_text describe_state_change (const evdesc::state_change &change) | |
1608 | final override | |
1609 | { | |
1610 | if (change.m_old_state == m_sm.get_start_state () | |
1611 | && assumed_non_null_p (change.m_new_state)) | |
1612 | { | |
1613 | m_first_deref_event = change.m_event_id; | |
0d6f7b1d | 1614 | m_deref_enode = change.m_event.get_exploded_node (); |
c4fd232f DM |
1615 | m_deref_expr = change.m_expr; |
1616 | return change.formatted_print ("pointer %qE is dereferenced here", | |
1617 | m_arg); | |
5c6546ca DM |
1618 | } |
1619 | return malloc_diagnostic::describe_state_change (change); | |
1620 | } | |
1621 | ||
1622 | label_text describe_final_event (const evdesc::final_event &ev) final override | |
1623 | { | |
0d6f7b1d | 1624 | m_check_enode = ev.m_event.get_exploded_node (); |
5c6546ca | 1625 | if (m_first_deref_event.known_p ()) |
c4fd232f DM |
1626 | return ev.formatted_print ("pointer %qE is checked for NULL here but" |
1627 | " it was already dereferenced at %@", | |
1628 | m_arg, &m_first_deref_event); | |
5c6546ca | 1629 | else |
c4fd232f DM |
1630 | return ev.formatted_print ("pointer %qE is checked for NULL here but" |
1631 | " it was already dereferenced", | |
1632 | m_arg); | |
5c6546ca DM |
1633 | } |
1634 | ||
1635 | private: | |
9093f275 DM |
1636 | static bool loop_header_p (const program_point &point) |
1637 | { | |
1638 | const supernode *snode = point.get_supernode (); | |
1639 | if (!snode) | |
1640 | return false; | |
1641 | for (auto &in_edge : snode->m_preds) | |
1642 | { | |
1643 | if (const cfg_superedge *cfg_in_edge | |
1644 | = in_edge->dyn_cast_cfg_superedge ()) | |
1645 | if (cfg_in_edge->back_edge_p ()) | |
1646 | return true; | |
1647 | } | |
1648 | return false; | |
1649 | } | |
1650 | ||
c4fd232f DM |
1651 | static bool sufficiently_similar_p (tree expr_a, tree expr_b) |
1652 | { | |
1653 | pretty_printer *pp_a = global_dc->printer->clone (); | |
1654 | pretty_printer *pp_b = global_dc->printer->clone (); | |
1655 | pp_printf (pp_a, "%qE", expr_a); | |
1656 | pp_printf (pp_b, "%qE", expr_b); | |
1657 | bool result = (strcmp (pp_formatted_text (pp_a), pp_formatted_text (pp_b)) | |
1658 | == 0); | |
1659 | delete pp_a; | |
1660 | delete pp_b; | |
1661 | return result; | |
1662 | } | |
1663 | ||
5c6546ca | 1664 | diagnostic_event_id_t m_first_deref_event; |
0d6f7b1d | 1665 | const exploded_node *m_deref_enode; |
c4fd232f | 1666 | tree m_deref_expr; |
0d6f7b1d | 1667 | const exploded_node *m_check_enode; |
5c6546ca DM |
1668 | }; |
1669 | ||
1690a839 DM |
1670 | /* struct allocation_state : public state_machine::state. */ |
1671 | ||
1672 | /* Implementation of state_machine::state::dump_to_pp vfunc | |
1673 | for allocation_state: append the API that this allocation is | |
1674 | associated with. */ | |
1675 | ||
1676 | void | |
1677 | allocation_state::dump_to_pp (pretty_printer *pp) const | |
1678 | { | |
1679 | state_machine::state::dump_to_pp (pp); | |
c7e276b8 DM |
1680 | if (m_deallocators) |
1681 | { | |
1682 | pp_string (pp, " ("); | |
1683 | m_deallocators->dump_to_pp (pp); | |
1684 | pp_character (pp, ')'); | |
1685 | } | |
1690a839 DM |
1686 | } |
1687 | ||
c7e276b8 DM |
1688 | /* Given a allocation_state for a deallocator_set, get the "nonnull" state |
1689 | for the corresponding allocator(s). */ | |
1690a839 DM |
1690 | |
1691 | const allocation_state * | |
1692 | allocation_state::get_nonnull () const | |
1693 | { | |
c7e276b8 DM |
1694 | gcc_assert (m_deallocators); |
1695 | return as_a_allocation_state (m_deallocators->m_nonnull); | |
1690a839 DM |
1696 | } |
1697 | ||
5c6546ca DM |
1698 | /* struct assumed_non_null_state : public allocation_state. */ |
1699 | ||
1700 | void | |
1701 | assumed_non_null_state::dump_to_pp (pretty_printer *pp) const | |
1702 | { | |
1703 | allocation_state::dump_to_pp (pp); | |
1704 | pp_string (pp, " (in "); | |
1705 | m_frame->dump_to_pp (pp, true); | |
1706 | pp_character (pp, ')'); | |
1707 | } | |
1708 | ||
757bf1df DM |
1709 | /* malloc_state_machine's ctor. */ |
1710 | ||
1711 | malloc_state_machine::malloc_state_machine (logger *logger) | |
1690a839 | 1712 | : state_machine ("malloc", logger), |
c7e276b8 DM |
1713 | m_free (this, "free", WORDING_FREED), |
1714 | m_scalar_delete (this, "delete", WORDING_DELETED), | |
a6baafca DM |
1715 | m_vector_delete (this, "delete[]", WORDING_DELETED), |
1716 | m_realloc (this, "realloc", WORDING_REALLOCATED) | |
1690a839 DM |
1717 | { |
1718 | gcc_assert (m_start->get_id () == 0); | |
c7e276b8 DM |
1719 | m_null = add_state ("null", RS_FREED, NULL, NULL); |
1720 | m_non_heap = add_state ("non-heap", RS_NON_HEAP, NULL, NULL); | |
1721 | m_stop = add_state ("stop", RS_STOP, NULL, NULL); | |
1722 | } | |
1723 | ||
1724 | malloc_state_machine::~malloc_state_machine () | |
1725 | { | |
1726 | unsigned i; | |
1727 | custom_deallocator_set *set; | |
1728 | FOR_EACH_VEC_ELT (m_dynamic_sets, i, set) | |
1729 | delete set; | |
1730 | custom_deallocator *d; | |
1731 | FOR_EACH_VEC_ELT (m_dynamic_deallocators, i, d) | |
1732 | delete d; | |
1690a839 DM |
1733 | } |
1734 | ||
1735 | state_machine::state_t | |
1736 | malloc_state_machine::add_state (const char *name, enum resource_state rs, | |
c7e276b8 DM |
1737 | const deallocator_set *deallocators, |
1738 | const deallocator *deallocator) | |
1690a839 DM |
1739 | { |
1740 | return add_custom_state (new allocation_state (name, alloc_state_id (), | |
c7e276b8 DM |
1741 | rs, deallocators, |
1742 | deallocator)); | |
1743 | } | |
1744 | ||
1745 | /* If ALLOCATOR_FNDECL has any "__attribute__((malloc(FOO)))", | |
1746 | return a custom_deallocator_set for them, consolidating them | |
1747 | to ensure uniqueness of the sets. | |
1748 | ||
1749 | Return NULL if it has no such attributes. */ | |
1750 | ||
1751 | const custom_deallocator_set * | |
1752 | malloc_state_machine:: | |
1753 | get_or_create_custom_deallocator_set (tree allocator_fndecl) | |
1754 | { | |
1755 | /* Early rejection of decls without attributes. */ | |
1756 | tree attrs = DECL_ATTRIBUTES (allocator_fndecl); | |
1757 | if (!attrs) | |
1758 | return NULL; | |
1759 | ||
1760 | /* Otherwise, call maybe_create_custom_deallocator_set, | |
1761 | memoizing the result. */ | |
1762 | if (custom_deallocator_set **slot | |
1763 | = m_custom_deallocator_set_cache.get (allocator_fndecl)) | |
1764 | return *slot; | |
1765 | custom_deallocator_set *set | |
1766 | = maybe_create_custom_deallocator_set (allocator_fndecl); | |
1767 | m_custom_deallocator_set_cache.put (allocator_fndecl, set); | |
1768 | return set; | |
1769 | } | |
1770 | ||
1771 | /* Given ALLOCATOR_FNDECL, a FUNCTION_DECL with attributes, | |
1772 | look for any "__attribute__((malloc(FOO)))" and return a | |
1773 | custom_deallocator_set for them, consolidating them | |
1774 | to ensure uniqueness of the sets. | |
1775 | ||
1776 | Return NULL if it has no such attributes. | |
1777 | ||
1778 | Subroutine of get_or_create_custom_deallocator_set which | |
1779 | memoizes the result. */ | |
1780 | ||
1781 | custom_deallocator_set * | |
1782 | malloc_state_machine:: | |
1783 | maybe_create_custom_deallocator_set (tree allocator_fndecl) | |
1784 | { | |
1785 | tree attrs = DECL_ATTRIBUTES (allocator_fndecl); | |
1786 | gcc_assert (attrs); | |
1787 | ||
1788 | /* Look for instances of __attribute__((malloc(FOO))). */ | |
1789 | auto_vec<const deallocator *> deallocator_vec; | |
1790 | for (tree allocs = attrs; | |
1791 | (allocs = lookup_attribute ("malloc", allocs)); | |
1792 | allocs = TREE_CHAIN (allocs)) | |
1793 | { | |
1794 | tree args = TREE_VALUE (allocs); | |
1795 | if (!args) | |
1796 | continue; | |
1797 | if (TREE_VALUE (args)) | |
1798 | { | |
1799 | const deallocator *d | |
1800 | = get_or_create_deallocator (TREE_VALUE (args)); | |
1801 | deallocator_vec.safe_push (d); | |
1802 | } | |
1803 | } | |
1804 | ||
1805 | /* If there weren't any deallocators, bail. */ | |
1806 | if (deallocator_vec.length () == 0) | |
1807 | return NULL; | |
1808 | ||
1809 | /* Consolidate, so that we reuse existing deallocator_set | |
1810 | instances. */ | |
1811 | deallocator_vec.qsort (deallocator::cmp_ptr_ptr); | |
1812 | custom_deallocator_set **slot | |
1813 | = m_custom_deallocator_set_map.get (&deallocator_vec); | |
1814 | if (slot) | |
1815 | return *slot; | |
1816 | custom_deallocator_set *set | |
1817 | = new custom_deallocator_set (this, &deallocator_vec, WORDING_DEALLOCATED); | |
1818 | m_custom_deallocator_set_map.put (&set->m_deallocator_vec, set); | |
1819 | m_dynamic_sets.safe_push (set); | |
1820 | return set; | |
1821 | } | |
1822 | ||
1823 | /* Get the deallocator for DEALLOCATOR_FNDECL, creating it if necessary. */ | |
1824 | ||
1825 | const deallocator * | |
1826 | malloc_state_machine::get_or_create_deallocator (tree deallocator_fndecl) | |
1827 | { | |
1828 | deallocator **slot = m_deallocator_map.get (deallocator_fndecl); | |
1829 | if (slot) | |
1830 | return *slot; | |
1831 | ||
1832 | /* Reuse "free". */ | |
1833 | deallocator *d; | |
1834 | if (is_named_call_p (deallocator_fndecl, "free") | |
84606efb SP |
1835 | || is_std_named_call_p (deallocator_fndecl, "free") |
1836 | || is_named_call_p (deallocator_fndecl, "__builtin_free")) | |
c7e276b8 DM |
1837 | d = &m_free.m_deallocator; |
1838 | else | |
1839 | { | |
1840 | custom_deallocator *cd | |
1841 | = new custom_deallocator (this, deallocator_fndecl, | |
1842 | WORDING_DEALLOCATED); | |
1843 | m_dynamic_deallocators.safe_push (cd); | |
1844 | d = cd; | |
1845 | } | |
1846 | m_deallocator_map.put (deallocator_fndecl, d); | |
1847 | return d; | |
757bf1df DM |
1848 | } |
1849 | ||
5c6546ca DM |
1850 | /* Get the "assumed-non-null" state for assumptions made within FRAME, |
1851 | creating it if necessary. */ | |
1852 | ||
1853 | state_machine::state_t | |
1854 | malloc_state_machine:: | |
1855 | get_or_create_assumed_non_null_state_for_frame (const frame_region *frame) | |
1856 | { | |
1857 | if (state_t *slot = m_assumed_non_null.get (frame)) | |
1858 | return *slot; | |
1859 | state_machine::state *new_state | |
1860 | = new assumed_non_null_state ("assumed-non-null", alloc_state_id (), frame); | |
1861 | add_custom_state (new_state); | |
1862 | m_assumed_non_null.put (frame, new_state); | |
1863 | return new_state; | |
1864 | } | |
1865 | ||
31534ac2 SP |
1866 | /* Try to identify the function declaration either by name or as a known malloc |
1867 | builtin. */ | |
1868 | ||
1869 | static bool | |
1870 | known_allocator_p (const_tree fndecl, const gcall *call) | |
1871 | { | |
1872 | /* Either it is a function we know by name and number of arguments... */ | |
1873 | if (is_named_call_p (fndecl, "malloc", call, 1) | |
1874 | || is_named_call_p (fndecl, "calloc", call, 2) | |
1875 | || is_std_named_call_p (fndecl, "malloc", call, 1) | |
1876 | || is_std_named_call_p (fndecl, "calloc", call, 2) | |
1877 | || is_named_call_p (fndecl, "strdup", call, 1) | |
1878 | || is_named_call_p (fndecl, "strndup", call, 2)) | |
1879 | return true; | |
1880 | ||
1881 | /* ... or it is a builtin allocator that allocates objects freed with | |
1882 | __builtin_free. */ | |
1a830c06 | 1883 | if (fndecl_built_in_p (fndecl, BUILT_IN_NORMAL)) |
31534ac2 SP |
1884 | switch (DECL_FUNCTION_CODE (fndecl)) |
1885 | { | |
1886 | case BUILT_IN_MALLOC: | |
1887 | case BUILT_IN_CALLOC: | |
1888 | case BUILT_IN_STRDUP: | |
1889 | case BUILT_IN_STRNDUP: | |
1890 | return true; | |
1891 | default: | |
1892 | break; | |
1893 | } | |
1894 | ||
1895 | return false; | |
1896 | } | |
1897 | ||
5c6546ca DM |
1898 | /* If PTR's nullness is not known, transition it to the "assumed-non-null" |
1899 | state for the current frame. */ | |
1900 | ||
1901 | void | |
1902 | malloc_state_machine::maybe_assume_non_null (sm_context *sm_ctxt, | |
1903 | tree ptr, | |
1904 | const gimple *stmt) const | |
1905 | { | |
1906 | const region_model *old_model = sm_ctxt->get_old_region_model (); | |
1907 | if (!old_model) | |
1908 | return; | |
1909 | ||
1910 | tree null_ptr_cst = build_int_cst (TREE_TYPE (ptr), 0); | |
1911 | tristate known_non_null | |
1912 | = old_model->eval_condition (ptr, NE_EXPR, null_ptr_cst, NULL); | |
1913 | if (known_non_null.is_unknown ()) | |
1914 | { | |
1915 | /* Cast away const-ness for cache-like operations. */ | |
1916 | malloc_state_machine *mut_this | |
1917 | = const_cast <malloc_state_machine *> (this); | |
1918 | state_t next_state | |
1919 | = mut_this->get_or_create_assumed_non_null_state_for_frame | |
1920 | (old_model->get_current_frame ()); | |
1921 | sm_ctxt->set_next_state (stmt, ptr, next_state); | |
1922 | } | |
1923 | } | |
1924 | ||
757bf1df DM |
1925 | /* Implementation of state_machine::on_stmt vfunc for malloc_state_machine. */ |
1926 | ||
1927 | bool | |
1928 | malloc_state_machine::on_stmt (sm_context *sm_ctxt, | |
1929 | const supernode *node, | |
1930 | const gimple *stmt) const | |
1931 | { | |
1932 | if (const gcall *call = dyn_cast <const gcall *> (stmt)) | |
1933 | if (tree callee_fndecl = sm_ctxt->get_fndecl_for_call (call)) | |
1934 | { | |
31534ac2 | 1935 | if (known_allocator_p (callee_fndecl, call)) |
757bf1df | 1936 | { |
c7e276b8 | 1937 | on_allocator_call (sm_ctxt, call, &m_free); |
1690a839 DM |
1938 | return true; |
1939 | } | |
1940 | ||
e7b26744 | 1941 | if (!is_placement_new_p (call)) |
1942 | { | |
1943 | bool returns_nonnull = !TREE_NOTHROW (callee_fndecl) | |
1944 | && flag_exceptions; | |
1945 | if (is_named_call_p (callee_fndecl, "operator new")) | |
1946 | on_allocator_call (sm_ctxt, call, | |
1947 | &m_scalar_delete, returns_nonnull); | |
1948 | else if (is_named_call_p (callee_fndecl, "operator new []")) | |
1949 | on_allocator_call (sm_ctxt, call, | |
1950 | &m_vector_delete, returns_nonnull); | |
1951 | } | |
1952 | ||
1953 | if (is_named_call_p (callee_fndecl, "operator delete", call, 1) | |
1954 | || is_named_call_p (callee_fndecl, "operator delete", call, 2)) | |
1690a839 | 1955 | { |
c7e276b8 DM |
1956 | on_deallocator_call (sm_ctxt, node, call, |
1957 | &m_scalar_delete.m_deallocator, 0); | |
1690a839 DM |
1958 | return true; |
1959 | } | |
1960 | else if (is_named_call_p (callee_fndecl, "operator delete []", call, 1)) | |
1961 | { | |
c7e276b8 DM |
1962 | on_deallocator_call (sm_ctxt, node, call, |
1963 | &m_vector_delete.m_deallocator, 0); | |
757bf1df DM |
1964 | return true; |
1965 | } | |
1966 | ||
1967 | if (is_named_call_p (callee_fndecl, "alloca", call, 1) | |
1968 | || is_named_call_p (callee_fndecl, "__builtin_alloca", call, 1)) | |
1969 | { | |
1970 | tree lhs = gimple_call_lhs (call); | |
1971 | if (lhs) | |
808f4dfe | 1972 | sm_ctxt->on_transition (node, stmt, lhs, m_start, m_non_heap); |
757bf1df DM |
1973 | return true; |
1974 | } | |
1975 | ||
1976 | if (is_named_call_p (callee_fndecl, "free", call, 1) | |
9f00b22f | 1977 | || is_std_named_call_p (callee_fndecl, "free", call, 1) |
757bf1df DM |
1978 | || is_named_call_p (callee_fndecl, "__builtin_free", call, 1)) |
1979 | { | |
c7e276b8 DM |
1980 | on_deallocator_call (sm_ctxt, node, call, |
1981 | &m_free.m_deallocator, 0); | |
757bf1df DM |
1982 | return true; |
1983 | } | |
1984 | ||
a6baafca | 1985 | if (is_named_call_p (callee_fndecl, "realloc", call, 2) |
5219414f | 1986 | || is_std_named_call_p (callee_fndecl, "realloc", call, 2) |
a6baafca DM |
1987 | || is_named_call_p (callee_fndecl, "__builtin_realloc", call, 2)) |
1988 | { | |
1989 | on_realloc_call (sm_ctxt, node, call); | |
1990 | return true; | |
1991 | } | |
1992 | ||
cd323d97 DM |
1993 | if (unaffected_by_call_p (callee_fndecl)) |
1994 | return true; | |
1995 | ||
c7e276b8 DM |
1996 | /* Cast away const-ness for cache-like operations. */ |
1997 | malloc_state_machine *mutable_this | |
1998 | = const_cast <malloc_state_machine *> (this); | |
1999 | ||
55f6a7d9 | 2000 | /* Handle interesting attributes of the callee_fndecl, |
2001 | or prioritize those of the builtin that callee_fndecl is expected | |
2002 | to be. | |
2003 | Might want this to be controlled by a flag. */ | |
2004 | { | |
2005 | tree fndecl = callee_fndecl; | |
2006 | /* If call is recognized as a builtin known_function, use that | |
2007 | builtin's function_decl. */ | |
2008 | if (const region_model *old_model = sm_ctxt->get_old_region_model ()) | |
2009 | if (const builtin_known_function *builtin_kf | |
2010 | = old_model->get_builtin_kf (call)) | |
2011 | fndecl = builtin_kf->builtin_decl (); | |
2012 | ||
2013 | /* Handle "__attribute__((malloc(FOO)))". */ | |
2014 | if (const deallocator_set *deallocators | |
c7e276b8 | 2015 | = mutable_this->get_or_create_custom_deallocator_set |
55f6a7d9 | 2016 | (fndecl)) |
2017 | { | |
2018 | tree attrs = TYPE_ATTRIBUTES (TREE_TYPE (fndecl)); | |
2019 | bool returns_nonnull | |
2020 | = lookup_attribute ("returns_nonnull", attrs); | |
2021 | on_allocator_call (sm_ctxt, call, deallocators, returns_nonnull); | |
2022 | } | |
2023 | ||
c7e276b8 | 2024 | { |
55f6a7d9 | 2025 | /* Handle "__attribute__((nonnull))". */ |
2026 | tree fntype = TREE_TYPE (fndecl); | |
2027 | bitmap nonnull_args = get_nonnull_args (fntype); | |
2028 | if (nonnull_args) | |
2029 | { | |
2030 | for (unsigned i = 0; i < gimple_call_num_args (stmt); i++) | |
2031 | { | |
2032 | tree arg = gimple_call_arg (stmt, i); | |
2033 | if (TREE_CODE (TREE_TYPE (arg)) != POINTER_TYPE) | |
2034 | continue; | |
2035 | /* If we have a nonnull-args, and either all pointers, or | |
2036 | just the specified pointers. */ | |
2037 | if (bitmap_empty_p (nonnull_args) | |
2038 | || bitmap_bit_p (nonnull_args, i)) | |
2039 | { | |
2040 | state_t state = sm_ctxt->get_state (stmt, arg); | |
2041 | /* Can't use a switch as the states are non-const. */ | |
2042 | /* Do use the fndecl that caused the warning so that the | |
2043 | misused attributes are printed and the user not | |
2044 | confused. */ | |
2045 | if (unchecked_p (state)) | |
2046 | { | |
2047 | tree diag_arg = sm_ctxt->get_diagnostic_tree (arg); | |
2048 | sm_ctxt->warn (node, stmt, arg, | |
2049 | make_unique<possible_null_arg> | |
2050 | (*this, diag_arg, fndecl, i)); | |
2051 | const allocation_state *astate | |
2052 | = as_a_allocation_state (state); | |
2053 | sm_ctxt->set_next_state (stmt, arg, | |
2054 | astate->get_nonnull ()); | |
2055 | } | |
2056 | else if (state == m_null) | |
2057 | { | |
2058 | tree diag_arg = sm_ctxt->get_diagnostic_tree (arg); | |
2059 | sm_ctxt->warn (node, stmt, arg, | |
2060 | make_unique<null_arg> | |
2061 | (*this, diag_arg, fndecl, i)); | |
2062 | sm_ctxt->set_next_state (stmt, arg, m_stop); | |
2063 | } | |
2064 | else if (state == m_start) | |
2065 | maybe_assume_non_null (sm_ctxt, arg, stmt); | |
2066 | } | |
2067 | } | |
2068 | BITMAP_FREE (nonnull_args); | |
2069 | } | |
c7e276b8 DM |
2070 | } |
2071 | ||
55f6a7d9 | 2072 | /* Check for this after nonnull, so that if we have both |
2073 | then we transition to "freed", rather than "checked". */ | |
2074 | unsigned dealloc_argno = fndecl_dealloc_argno (fndecl); | |
2075 | if (dealloc_argno != UINT_MAX) | |
757bf1df | 2076 | { |
55f6a7d9 | 2077 | const deallocator *d |
2078 | = mutable_this->get_or_create_deallocator (fndecl); | |
2079 | on_deallocator_call (sm_ctxt, node, call, d, dealloc_argno); | |
757bf1df DM |
2080 | } |
2081 | } | |
2082 | } | |
2083 | ||
5c6546ca DM |
2084 | /* Look for pointers explicitly being compared against zero |
2085 | that are in state assumed_non_null i.e. we already defererenced | |
2086 | them. | |
2087 | We have to do this check here, rather than in on_condition | |
2088 | because we add a constraint that the pointer is non-null when | |
2089 | dereferencing it, and this makes the apply_constraints_for_gcond | |
2090 | find known-true and known-false conditions; on_condition is only | |
2091 | called when adding new constraints. */ | |
2092 | if (const gcond *cond_stmt = dyn_cast <const gcond *> (stmt)) | |
2093 | { | |
2094 | enum tree_code op = gimple_cond_code (cond_stmt); | |
2095 | if (op == EQ_EXPR || op == NE_EXPR) | |
2096 | { | |
2097 | tree lhs = gimple_cond_lhs (cond_stmt); | |
2098 | tree rhs = gimple_cond_rhs (cond_stmt); | |
2099 | if (any_pointer_p (lhs) | |
2100 | && any_pointer_p (rhs) | |
2101 | && zerop (rhs)) | |
2102 | { | |
2103 | state_t state = sm_ctxt->get_state (stmt, lhs); | |
2104 | if (assumed_non_null_p (state)) | |
2105 | maybe_complain_about_deref_before_check | |
2106 | (sm_ctxt, node, | |
2107 | stmt, | |
2108 | (const assumed_non_null_state *)state, | |
2109 | lhs); | |
2110 | } | |
2111 | } | |
2112 | } | |
2113 | ||
808f4dfe | 2114 | if (tree lhs = sm_ctxt->is_zero_assignment (stmt)) |
8525d1f5 | 2115 | if (any_pointer_p (lhs)) |
1690a839 | 2116 | on_zero_assignment (sm_ctxt, stmt,lhs); |
757bf1df | 2117 | |
757bf1df DM |
2118 | /* Handle dereferences. */ |
2119 | for (unsigned i = 0; i < gimple_num_ops (stmt); i++) | |
2120 | { | |
2121 | tree op = gimple_op (stmt, i); | |
2122 | if (!op) | |
2123 | continue; | |
2124 | if (TREE_CODE (op) == COMPONENT_REF) | |
2125 | op = TREE_OPERAND (op, 0); | |
2126 | ||
2127 | if (TREE_CODE (op) == MEM_REF) | |
2128 | { | |
2129 | tree arg = TREE_OPERAND (op, 0); | |
757bf1df | 2130 | |
25ef215a | 2131 | state_t state = sm_ctxt->get_state (stmt, arg); |
5c6546ca DM |
2132 | if (state == m_start) |
2133 | maybe_assume_non_null (sm_ctxt, arg, stmt); | |
2134 | else if (unchecked_p (state)) | |
25ef215a | 2135 | { |
0f9aa35c | 2136 | tree diag_arg = sm_ctxt->get_diagnostic_tree (arg); |
25ef215a | 2137 | sm_ctxt->warn (node, stmt, arg, |
6341f14e DM |
2138 | make_unique<possible_null_deref> (*this, |
2139 | diag_arg)); | |
1690a839 DM |
2140 | const allocation_state *astate = as_a_allocation_state (state); |
2141 | sm_ctxt->set_next_state (stmt, arg, astate->get_nonnull ()); | |
25ef215a DM |
2142 | } |
2143 | else if (state == m_null) | |
2144 | { | |
0f9aa35c | 2145 | tree diag_arg = sm_ctxt->get_diagnostic_tree (arg); |
25ef215a | 2146 | sm_ctxt->warn (node, stmt, arg, |
6341f14e | 2147 | make_unique<null_deref> (*this, diag_arg)); |
25ef215a DM |
2148 | sm_ctxt->set_next_state (stmt, arg, m_stop); |
2149 | } | |
1690a839 | 2150 | else if (freed_p (state)) |
25ef215a | 2151 | { |
0f9aa35c | 2152 | tree diag_arg = sm_ctxt->get_diagnostic_tree (arg); |
1690a839 | 2153 | const allocation_state *astate = as_a_allocation_state (state); |
25ef215a | 2154 | sm_ctxt->warn (node, stmt, arg, |
6341f14e DM |
2155 | make_unique<use_after_free> |
2156 | (*this, diag_arg, astate->m_deallocator)); | |
25ef215a DM |
2157 | sm_ctxt->set_next_state (stmt, arg, m_stop); |
2158 | } | |
757bf1df DM |
2159 | } |
2160 | } | |
2161 | return false; | |
2162 | } | |
2163 | ||
5c6546ca DM |
2164 | /* Given a check against null of PTR in assumed-non-null state STATE, |
2165 | potentially add a deref_before_check warning to SM_CTXT. */ | |
2166 | ||
2167 | void | |
2168 | malloc_state_machine:: | |
2169 | maybe_complain_about_deref_before_check (sm_context *sm_ctxt, | |
2170 | const supernode *node, | |
2171 | const gimple *stmt, | |
2172 | const assumed_non_null_state *state, | |
2173 | tree ptr) const | |
2174 | { | |
2175 | const region_model *model = sm_ctxt->get_old_region_model (); | |
2176 | if (!model) | |
2177 | return; | |
2178 | ||
2179 | /* Don't complain if the current frame (where the check is occurring) is | |
2180 | deeper than the frame in which the "not null" assumption was made. | |
2181 | This suppress false positives for cases like: | |
2182 | ||
2183 | void foo (struct s *p) | |
2184 | { | |
2185 | int val = s->some_field; // deref here | |
2186 | shared_helper (p); | |
2187 | } | |
2188 | ||
2189 | where "shared_helper" has: | |
2190 | ||
2191 | void shared_helper (struct s *p) | |
2192 | { | |
2193 | if (!p) // check here | |
2194 | return; | |
2195 | // etc | |
2196 | } | |
2197 | ||
2198 | since the check in "shared_helper" is OK. */ | |
2199 | const frame_region *checked_in_frame = model->get_current_frame (); | |
2200 | const frame_region *assumed_nonnull_in_frame = state->m_frame; | |
2201 | if (checked_in_frame->get_index () > assumed_nonnull_in_frame->get_index ()) | |
2202 | return; | |
2203 | ||
5743e189 DM |
2204 | /* Don't complain if STMT was inlined from another function, to avoid |
2205 | similar false positives involving shared helper functions. */ | |
2206 | if (stmt->location) | |
2207 | { | |
2208 | inlining_info info (stmt->location); | |
2209 | if (info.get_extra_frames () > 0) | |
2210 | return; | |
2211 | } | |
2212 | ||
5c6546ca | 2213 | tree diag_ptr = sm_ctxt->get_diagnostic_tree (ptr); |
c4fd232f DM |
2214 | if (diag_ptr) |
2215 | sm_ctxt->warn | |
2216 | (node, stmt, ptr, | |
2217 | make_unique<deref_before_check> (*this, diag_ptr)); | |
5c6546ca DM |
2218 | sm_ctxt->set_next_state (stmt, ptr, m_stop); |
2219 | } | |
2220 | ||
c7e276b8 DM |
2221 | /* Handle a call to an allocator. |
2222 | RETURNS_NONNULL is true if CALL is to a fndecl known to have | |
2223 | __attribute__((returns_nonnull)). */ | |
1690a839 DM |
2224 | |
2225 | void | |
2226 | malloc_state_machine::on_allocator_call (sm_context *sm_ctxt, | |
2227 | const gcall *call, | |
c7e276b8 DM |
2228 | const deallocator_set *deallocators, |
2229 | bool returns_nonnull) const | |
1690a839 DM |
2230 | { |
2231 | tree lhs = gimple_call_lhs (call); | |
2232 | if (lhs) | |
2233 | { | |
2234 | if (sm_ctxt->get_state (call, lhs) == m_start) | |
c7e276b8 DM |
2235 | sm_ctxt->set_next_state (call, lhs, |
2236 | (returns_nonnull | |
2237 | ? deallocators->m_nonnull | |
2238 | : deallocators->m_unchecked)); | |
1690a839 DM |
2239 | } |
2240 | else | |
2241 | { | |
2242 | /* TODO: report leak. */ | |
2243 | } | |
2244 | } | |
2245 | ||
a61aaee6 DM |
2246 | /* Handle deallocations of non-heap pointers. |
2247 | non-heap -> stop, with warning. */ | |
2248 | ||
2249 | void | |
2250 | malloc_state_machine::handle_free_of_non_heap (sm_context *sm_ctxt, | |
2251 | const supernode *node, | |
2252 | const gcall *call, | |
2253 | tree arg, | |
2254 | const deallocator *d) const | |
2255 | { | |
2256 | tree diag_arg = sm_ctxt->get_diagnostic_tree (arg); | |
2257 | const region *freed_reg = NULL; | |
2258 | if (const program_state *old_state = sm_ctxt->get_old_program_state ()) | |
2259 | { | |
2260 | const region_model *old_model = old_state->m_region_model; | |
2261 | const svalue *ptr_sval = old_model->get_rvalue (arg, NULL); | |
2262 | freed_reg = old_model->deref_rvalue (ptr_sval, arg, NULL); | |
2263 | } | |
2264 | sm_ctxt->warn (node, call, arg, | |
6341f14e DM |
2265 | make_unique<free_of_non_heap> |
2266 | (*this, diag_arg, freed_reg, d->m_name)); | |
a61aaee6 DM |
2267 | sm_ctxt->set_next_state (call, arg, m_stop); |
2268 | } | |
2269 | ||
1690a839 DM |
2270 | void |
2271 | malloc_state_machine::on_deallocator_call (sm_context *sm_ctxt, | |
2272 | const supernode *node, | |
2273 | const gcall *call, | |
c7e276b8 DM |
2274 | const deallocator *d, |
2275 | unsigned argno) const | |
1690a839 | 2276 | { |
c7e276b8 DM |
2277 | if (argno >= gimple_call_num_args (call)) |
2278 | return; | |
2279 | tree arg = gimple_call_arg (call, argno); | |
1690a839 DM |
2280 | |
2281 | state_t state = sm_ctxt->get_state (call, arg); | |
2282 | ||
5c6546ca DM |
2283 | /* start/assumed_non_null/unchecked/nonnull -> freed. */ |
2284 | if (state == m_start || assumed_non_null_p (state)) | |
c7e276b8 | 2285 | sm_ctxt->set_next_state (call, arg, d->m_freed); |
1690a839 DM |
2286 | else if (unchecked_p (state) || nonnull_p (state)) |
2287 | { | |
2288 | const allocation_state *astate = as_a_allocation_state (state); | |
c7e276b8 DM |
2289 | gcc_assert (astate->m_deallocators); |
2290 | if (!astate->m_deallocators->contains_p (d)) | |
1690a839 DM |
2291 | { |
2292 | /* Wrong allocator. */ | |
0f9aa35c | 2293 | tree diag_arg = sm_ctxt->get_diagnostic_tree (arg); |
6341f14e DM |
2294 | sm_ctxt->warn (node, call, arg, |
2295 | make_unique<mismatching_deallocation> | |
2296 | (*this, diag_arg, | |
2297 | astate->m_deallocators, | |
2298 | d)); | |
1690a839 | 2299 | } |
c7e276b8 | 2300 | sm_ctxt->set_next_state (call, arg, d->m_freed); |
1690a839 DM |
2301 | } |
2302 | ||
2303 | /* Keep state "null" as-is, rather than transitioning to "freed"; | |
2304 | we don't want to complain about double-free of NULL. */ | |
c7e276b8 | 2305 | else if (state == d->m_freed) |
1690a839 DM |
2306 | { |
2307 | /* freed -> stop, with warning. */ | |
0f9aa35c | 2308 | tree diag_arg = sm_ctxt->get_diagnostic_tree (arg); |
1690a839 | 2309 | sm_ctxt->warn (node, call, arg, |
6341f14e | 2310 | make_unique<double_free> (*this, diag_arg, d->m_name)); |
1690a839 DM |
2311 | sm_ctxt->set_next_state (call, arg, m_stop); |
2312 | } | |
2313 | else if (state == m_non_heap) | |
2314 | { | |
2315 | /* non-heap -> stop, with warning. */ | |
a61aaee6 | 2316 | handle_free_of_non_heap (sm_ctxt, node, call, arg, d); |
1690a839 DM |
2317 | } |
2318 | } | |
2319 | ||
eafa9d96 DM |
2320 | /* Handle a call to "realloc". |
2321 | Check for free of non-heap or mismatching allocators, | |
2322 | transitioning to the "stop" state for such cases. | |
a6baafca | 2323 | |
6bd31b33 | 2324 | Otherwise, kf_realloc::impl_call_post will later |
eafa9d96 DM |
2325 | get called (which will handle other sm-state transitions |
2326 | when the state is bifurcated). */ | |
a6baafca DM |
2327 | |
2328 | void | |
2329 | malloc_state_machine::on_realloc_call (sm_context *sm_ctxt, | |
eafa9d96 | 2330 | const supernode *node, |
a6baafca DM |
2331 | const gcall *call) const |
2332 | { | |
eafa9d96 DM |
2333 | const unsigned argno = 0; |
2334 | const deallocator *d = &m_realloc; | |
2335 | ||
2336 | tree arg = gimple_call_arg (call, argno); | |
a6baafca | 2337 | |
eafa9d96 | 2338 | state_t state = sm_ctxt->get_state (call, arg); |
a6baafca | 2339 | |
a6baafca DM |
2340 | if (unchecked_p (state) || nonnull_p (state)) |
2341 | { | |
2342 | const allocation_state *astate = as_a_allocation_state (state); | |
2343 | gcc_assert (astate->m_deallocators); | |
eafa9d96 | 2344 | if (!astate->m_deallocators->contains_p (&m_free.m_deallocator)) |
a6baafca DM |
2345 | { |
2346 | /* Wrong allocator. */ | |
eafa9d96 | 2347 | tree diag_arg = sm_ctxt->get_diagnostic_tree (arg); |
6341f14e DM |
2348 | sm_ctxt->warn (node, call, arg, |
2349 | make_unique<mismatching_deallocation> | |
2350 | (*this, diag_arg, | |
2351 | astate->m_deallocators, d)); | |
eafa9d96 DM |
2352 | sm_ctxt->set_next_state (call, arg, m_stop); |
2353 | if (path_context *path_ctxt = sm_ctxt->get_path_context ()) | |
2354 | path_ctxt->terminate_path (); | |
a6baafca DM |
2355 | } |
2356 | } | |
eafa9d96 DM |
2357 | else if (state == m_free.m_deallocator.m_freed) |
2358 | { | |
2359 | /* freed -> stop, with warning. */ | |
2360 | tree diag_arg = sm_ctxt->get_diagnostic_tree (arg); | |
2361 | sm_ctxt->warn (node, call, arg, | |
6341f14e | 2362 | make_unique<double_free> (*this, diag_arg, "free")); |
eafa9d96 DM |
2363 | sm_ctxt->set_next_state (call, arg, m_stop); |
2364 | if (path_context *path_ctxt = sm_ctxt->get_path_context ()) | |
2365 | path_ctxt->terminate_path (); | |
2366 | } | |
2367 | else if (state == m_non_heap) | |
2368 | { | |
2369 | /* non-heap -> stop, with warning. */ | |
a61aaee6 | 2370 | handle_free_of_non_heap (sm_ctxt, node, call, arg, d); |
eafa9d96 DM |
2371 | if (path_context *path_ctxt = sm_ctxt->get_path_context ()) |
2372 | path_ctxt->terminate_path (); | |
2373 | } | |
a6baafca DM |
2374 | } |
2375 | ||
8525d1f5 DM |
2376 | /* Implementation of state_machine::on_phi vfunc for malloc_state_machine. */ |
2377 | ||
2378 | void | |
2379 | malloc_state_machine::on_phi (sm_context *sm_ctxt, | |
1690a839 | 2380 | const supernode *node ATTRIBUTE_UNUSED, |
8525d1f5 DM |
2381 | const gphi *phi, |
2382 | tree rhs) const | |
2383 | { | |
2384 | if (zerop (rhs)) | |
2385 | { | |
2386 | tree lhs = gimple_phi_result (phi); | |
1690a839 | 2387 | on_zero_assignment (sm_ctxt, phi, lhs); |
8525d1f5 DM |
2388 | } |
2389 | } | |
2390 | ||
757bf1df DM |
2391 | /* Implementation of state_machine::on_condition vfunc for malloc_state_machine. |
2392 | Potentially transition state 'unchecked' to 'nonnull' or to 'null'. */ | |
2393 | ||
2394 | void | |
2395 | malloc_state_machine::on_condition (sm_context *sm_ctxt, | |
1690a839 | 2396 | const supernode *node ATTRIBUTE_UNUSED, |
757bf1df | 2397 | const gimple *stmt, |
48e8a7a6 | 2398 | const svalue *lhs, |
757bf1df | 2399 | enum tree_code op, |
48e8a7a6 | 2400 | const svalue *rhs) const |
757bf1df | 2401 | { |
48e8a7a6 | 2402 | if (!rhs->all_zeroes_p ()) |
757bf1df DM |
2403 | return; |
2404 | ||
2405 | if (!any_pointer_p (lhs)) | |
2406 | return; | |
2407 | if (!any_pointer_p (rhs)) | |
2408 | return; | |
2409 | ||
2410 | if (op == NE_EXPR) | |
2411 | { | |
2412 | log ("got 'ARG != 0' match"); | |
1690a839 DM |
2413 | state_t s = sm_ctxt->get_state (stmt, lhs); |
2414 | if (unchecked_p (s)) | |
2415 | { | |
2416 | const allocation_state *astate = as_a_allocation_state (s); | |
2417 | sm_ctxt->set_next_state (stmt, lhs, astate->get_nonnull ()); | |
2418 | } | |
757bf1df DM |
2419 | } |
2420 | else if (op == EQ_EXPR) | |
2421 | { | |
2422 | log ("got 'ARG == 0' match"); | |
1690a839 DM |
2423 | state_t s = sm_ctxt->get_state (stmt, lhs); |
2424 | if (unchecked_p (s)) | |
2425 | sm_ctxt->set_next_state (stmt, lhs, m_null); | |
757bf1df DM |
2426 | } |
2427 | } | |
2428 | ||
5c6546ca DM |
2429 | /* Implementation of state_machine::on_pop_frame vfunc for malloc_state_machine. |
2430 | Clear any "assumed-non-null" state where the assumption happened in | |
2431 | FRAME_REG. */ | |
2432 | ||
2433 | void | |
2434 | malloc_state_machine::on_pop_frame (sm_state_map *smap, | |
2435 | const frame_region *frame_reg) const | |
2436 | { | |
2437 | hash_set<const svalue *> svals_to_clear; | |
2438 | for (auto kv : *smap) | |
2439 | { | |
2440 | const svalue *sval = kv.first; | |
2441 | state_t state = kv.second.m_state; | |
2442 | if (assumed_non_null_p (state)) | |
2443 | { | |
2444 | const assumed_non_null_state *assumed_state | |
2445 | = (const assumed_non_null_state *)state; | |
2446 | if (frame_reg == assumed_state->m_frame) | |
2447 | svals_to_clear.add (sval); | |
2448 | } | |
2449 | } | |
2450 | for (auto sval : svals_to_clear) | |
2451 | smap->clear_any_state (sval); | |
2452 | } | |
2453 | ||
757bf1df DM |
2454 | /* Implementation of state_machine::can_purge_p vfunc for malloc_state_machine. |
2455 | Don't allow purging of pointers in state 'unchecked' or 'nonnull' | |
2456 | (to avoid false leak reports). */ | |
2457 | ||
2458 | bool | |
2459 | malloc_state_machine::can_purge_p (state_t s) const | |
2460 | { | |
1690a839 DM |
2461 | enum resource_state rs = get_rs (s); |
2462 | return rs != RS_UNCHECKED && rs != RS_NONNULL; | |
757bf1df DM |
2463 | } |
2464 | ||
2465 | /* Implementation of state_machine::on_leak vfunc for malloc_state_machine | |
2466 | (for complaining about leaks of pointers in state 'unchecked' and | |
2467 | 'nonnull'). */ | |
2468 | ||
6341f14e | 2469 | std::unique_ptr<pending_diagnostic> |
757bf1df DM |
2470 | malloc_state_machine::on_leak (tree var) const |
2471 | { | |
6341f14e | 2472 | return make_unique<malloc_leak> (*this, var); |
757bf1df DM |
2473 | } |
2474 | ||
808f4dfe DM |
2475 | /* Implementation of state_machine::reset_when_passed_to_unknown_fn_p vfunc |
2476 | for malloc_state_machine. */ | |
2477 | ||
2478 | bool | |
2479 | malloc_state_machine::reset_when_passed_to_unknown_fn_p (state_t s, | |
2480 | bool is_mutable) const | |
2481 | { | |
2482 | /* An on-stack ptr doesn't stop being stack-allocated when passed to an | |
2483 | unknown fn. */ | |
2484 | if (s == m_non_heap) | |
2485 | return false; | |
2486 | ||
2487 | /* Otherwise, pointers passed as non-const can be freed. */ | |
2488 | return is_mutable; | |
2489 | } | |
2490 | ||
5c6546ca DM |
2491 | /* Implementation of state_machine::maybe_get_merged_states_nonequal vfunc |
2492 | for malloc_state_machine. | |
2493 | ||
2494 | Support discarding "assumed-non-null" states when merging with | |
2495 | start state. */ | |
2496 | ||
2497 | state_machine::state_t | |
2498 | malloc_state_machine::maybe_get_merged_states_nonequal (state_t state_a, | |
2499 | state_t state_b) const | |
2500 | { | |
2501 | if (assumed_non_null_p (state_a) && state_b == m_start) | |
2502 | return m_start; | |
2503 | if (state_a == m_start && assumed_non_null_p (state_b)) | |
2504 | return m_start; | |
2505 | return NULL; | |
2506 | } | |
2507 | ||
cd323d97 DM |
2508 | /* Return true if calls to FNDECL are known to not affect this sm-state. */ |
2509 | ||
2510 | bool | |
2511 | malloc_state_machine::unaffected_by_call_p (tree fndecl) | |
2512 | { | |
2513 | /* A set of functions that are known to not affect allocation | |
2514 | status, even if we haven't fully modelled the rest of their | |
2515 | behavior yet. */ | |
2516 | static const char * const funcnames[] = { | |
2517 | /* This array must be kept sorted. */ | |
2518 | "strsep", | |
2519 | }; | |
ca32b29e | 2520 | const size_t count = ARRAY_SIZE (funcnames); |
cd323d97 DM |
2521 | function_set fs (funcnames, count); |
2522 | ||
2523 | if (fs.contains_decl_p (fndecl)) | |
2524 | return true; | |
2525 | ||
2526 | return false; | |
2527 | } | |
2528 | ||
8525d1f5 DM |
2529 | /* Shared logic for handling GIMPLE_ASSIGNs and GIMPLE_PHIs that |
2530 | assign zero to LHS. */ | |
2531 | ||
2532 | void | |
2533 | malloc_state_machine::on_zero_assignment (sm_context *sm_ctxt, | |
8525d1f5 DM |
2534 | const gimple *stmt, |
2535 | tree lhs) const | |
2536 | { | |
1690a839 DM |
2537 | state_t s = sm_ctxt->get_state (stmt, lhs); |
2538 | enum resource_state rs = get_rs (s); | |
2539 | if (rs == RS_START | |
2540 | || rs == RS_UNCHECKED | |
2541 | || rs == RS_NONNULL | |
2542 | || rs == RS_FREED) | |
2543 | sm_ctxt->set_next_state (stmt, lhs, m_null); | |
8525d1f5 DM |
2544 | } |
2545 | ||
eafa9d96 DM |
2546 | /* Special-case hook for handling realloc, for the "success with move to |
2547 | a new buffer" case, marking OLD_PTR_SVAL as freed and NEW_PTR_SVAL as | |
2548 | non-null. | |
2549 | ||
2550 | This is similar to on_deallocator_call and on_allocator_call, | |
2551 | but the checks happen in on_realloc_call, and by splitting the states. */ | |
2552 | ||
2553 | void | |
2554 | malloc_state_machine:: | |
2555 | on_realloc_with_move (region_model *model, | |
2556 | sm_state_map *smap, | |
2557 | const svalue *old_ptr_sval, | |
2558 | const svalue *new_ptr_sval, | |
2559 | const extrinsic_state &ext_state) const | |
2560 | { | |
2561 | smap->set_state (model, old_ptr_sval, | |
2562 | m_free.m_deallocator.m_freed, | |
2563 | NULL, ext_state); | |
2564 | ||
2565 | smap->set_state (model, new_ptr_sval, | |
2566 | m_free.m_nonnull, | |
2567 | NULL, ext_state); | |
2568 | } | |
2569 | ||
38c00edd EF |
2570 | /* Hook for get_or_create_region_for_heap_alloc for the case when we want |
2571 | ptr_sval to mark a newly created region as assumed non null on malloc SM. */ | |
2572 | void | |
2573 | malloc_state_machine::transition_ptr_sval_non_null (region_model *model, | |
2574 | sm_state_map *smap, | |
2575 | const svalue *new_ptr_sval, | |
2576 | const extrinsic_state &ext_state) const | |
2577 | { | |
2578 | smap->set_state (model, new_ptr_sval, m_free.m_nonnull, NULL, ext_state); | |
2579 | } | |
2580 | ||
757bf1df DM |
2581 | } // anonymous namespace |
2582 | ||
2583 | /* Internal interface to this file. */ | |
2584 | ||
2585 | state_machine * | |
2586 | make_malloc_state_machine (logger *logger) | |
2587 | { | |
2588 | return new malloc_state_machine (logger); | |
2589 | } | |
2590 | ||
eafa9d96 | 2591 | /* Specialcase hook for handling realloc, for use by |
6bd31b33 | 2592 | kf_realloc::impl_call_post::success_with_move::update_model. */ |
eafa9d96 DM |
2593 | |
2594 | void | |
2595 | region_model::on_realloc_with_move (const call_details &cd, | |
2596 | const svalue *old_ptr_sval, | |
2597 | const svalue *new_ptr_sval) | |
2598 | { | |
2599 | region_model_context *ctxt = cd.get_ctxt (); | |
2600 | if (!ctxt) | |
2601 | return; | |
2602 | const extrinsic_state *ext_state = ctxt->get_ext_state (); | |
2603 | if (!ext_state) | |
2604 | return; | |
2605 | ||
2606 | sm_state_map *smap; | |
2607 | const state_machine *sm; | |
2608 | unsigned sm_idx; | |
2609 | if (!ctxt->get_malloc_map (&smap, &sm, &sm_idx)) | |
2610 | return; | |
2611 | ||
2612 | gcc_assert (smap); | |
2613 | gcc_assert (sm); | |
2614 | ||
2615 | const malloc_state_machine &malloc_sm | |
2616 | = (const malloc_state_machine &)*sm; | |
2617 | ||
2618 | malloc_sm.on_realloc_with_move (this, | |
2619 | smap, | |
2620 | old_ptr_sval, | |
2621 | new_ptr_sval, | |
2622 | *ext_state); | |
2623 | } | |
2624 | ||
38c00edd EF |
2625 | /* Moves ptr_sval from start to assumed non-null, for use by |
2626 | region_model::get_or_create_region_for_heap_alloc. */ | |
2627 | void | |
2628 | region_model::transition_ptr_sval_non_null (region_model_context *ctxt, | |
2629 | const svalue *ptr_sval) | |
2630 | { | |
2631 | if (!ctxt) | |
2632 | return; | |
2633 | const extrinsic_state *ext_state = ctxt->get_ext_state (); | |
2634 | if (!ext_state) | |
2635 | return; | |
2636 | ||
2637 | sm_state_map *smap; | |
2638 | const state_machine *sm; | |
2639 | unsigned sm_idx; | |
2640 | if (!ctxt->get_malloc_map (&smap, &sm, &sm_idx)) | |
2641 | return; | |
2642 | ||
2643 | gcc_assert (smap); | |
2644 | gcc_assert (sm); | |
2645 | ||
2646 | const malloc_state_machine &malloc_sm = (const malloc_state_machine &)*sm; | |
2647 | ||
2648 | malloc_sm.transition_ptr_sval_non_null (this, smap, ptr_sval, *ext_state); | |
2649 | } | |
2650 | ||
75038aa6 DM |
2651 | } // namespace ana |
2652 | ||
757bf1df | 2653 | #endif /* #if ENABLE_ANALYZER */ |