1 /*
2 * Copyright (C) 2010 Dan Carpenter.
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License
6 * as published by the Free Software Foundation; either version 2
7 * of the License, or (at your option) any later version.
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, see http://www.gnu.org/copyleft/gpl.txt
16 */
17
18 #include <stdlib.h>
19 #include <errno.h>
20 #include "parse.h"
21 #include "smatch.h"
22 #include "smatch_slist.h"
23 #include "smatch_extra.h"
24 #include "smatch_function_hashtable.h"
25
26 #define UNKNOWN_SIZE -1
27
28 static int my_size_id;
29
30 static DEFINE_HASHTABLE_INSERT(insert_func, char, int);
31 static DEFINE_HASHTABLE_SEARCH(search_func, char, int);
32 static struct hashtable *allocation_funcs;
33
get_fn_name(struct expression * expr)34 static char *get_fn_name(struct expression *expr)
35 {
36 if (expr->type != EXPR_CALL)
37 return NULL;
38 if (expr->fn->type != EXPR_SYMBOL)
39 return NULL;
40 return expr_to_var(expr->fn);
41 }
42
is_allocation_function(struct expression * expr)43 static int is_allocation_function(struct expression *expr)
44 {
45 char *func;
46 int ret = 0;
47
48 func = get_fn_name(expr);
49 if (!func)
50 return 0;
51 if (search_func(allocation_funcs, func))
52 ret = 1;
53 free_string(func);
54 return ret;
55 }
56
add_allocation_function(const char * func,void * call_back,int param)57 static void add_allocation_function(const char *func, void *call_back, int param)
58 {
59 insert_func(allocation_funcs, (char *)func, (int *)1);
60 add_function_assign_hook(func, call_back, INT_PTR(param));
61 }
62
estate_to_size(struct smatch_state * state)63 static int estate_to_size(struct smatch_state *state)
64 {
65 sval_t sval;
66
67 if (!state || !estate_rl(state))
68 return 0;
69 sval = estate_max(state);
70 return sval.value;
71 }
72
size_to_estate(int size)73 static struct smatch_state *size_to_estate(int size)
74 {
75 sval_t sval;
76
77 sval.type = &int_ctype;
78 sval.value = size;
79
80 return alloc_estate_sval(sval);
81 }
82
size_to_rl(int size)83 static struct range_list *size_to_rl(int size)
84 {
85 sval_t sval;
86
87 sval.type = &int_ctype;
88 sval.value = size;
89
90 return alloc_rl(sval, sval);
91 }
92
unmatched_size_state(struct sm_state * sm)93 static struct smatch_state *unmatched_size_state(struct sm_state *sm)
94 {
95 return size_to_estate(UNKNOWN_SIZE);
96 }
97
set_size_undefined(struct sm_state * sm,struct expression * mod_expr)98 static void set_size_undefined(struct sm_state *sm, struct expression *mod_expr)
99 {
100 set_state(sm->owner, sm->name, sm->sym, size_to_estate(UNKNOWN_SIZE));
101 }
102
merge_size_func(struct smatch_state * s1,struct smatch_state * s2)103 static struct smatch_state *merge_size_func(struct smatch_state *s1, struct smatch_state *s2)
104 {
105 return merge_estates(s1, s2);
106 }
107
set_param_buf_size(const char * name,struct symbol * sym,char * key,char * value)108 void set_param_buf_size(const char *name, struct symbol *sym, char *key, char *value)
109 {
110 struct range_list *rl = NULL;
111 struct smatch_state *state;
112 char fullname[256];
113
114 if (strncmp(key, "$", 1) != 0)
115 return;
116
117 snprintf(fullname, 256, "%s%s", name, key + 1);
118
119 str_to_rl(&int_ctype, value, &rl);
120 if (!rl || is_whole_rl(rl))
121 return;
122 state = alloc_estate_rl(rl);
123 set_state(my_size_id, fullname, sym, state);
124 }
125
bytes_per_element(struct expression * expr)126 static int bytes_per_element(struct expression *expr)
127 {
128 struct symbol *type;
129
130 if (!expr)
131 return 0;
132 if (expr->type == EXPR_STRING)
133 return 1;
134 if (expr->type == EXPR_PREOP && expr->op == '&') {
135 type = get_type(expr->unop);
136 if (type && type->type == SYM_ARRAY)
137 expr = expr->unop;
138 }
139 type = get_type(expr);
140 if (!type)
141 return 0;
142
143 if (type->type != SYM_PTR && type->type != SYM_ARRAY)
144 return 0;
145
146 type = get_base_type(type);
147 return type_bytes(type);
148 }
149
bytes_to_elements(struct expression * expr,int bytes)150 static int bytes_to_elements(struct expression *expr, int bytes)
151 {
152 int bpe;
153
154 bpe = bytes_per_element(expr);
155 if (bpe == 0)
156 return 0;
157 return bytes / bpe;
158 }
159
elements_to_bytes(struct expression * expr,int elements)160 static int elements_to_bytes(struct expression *expr, int elements)
161 {
162 int bpe;
163
164 bpe = bytes_per_element(expr);
165 return elements * bpe;
166 }
167
get_initializer_size(struct expression * expr)168 static int get_initializer_size(struct expression *expr)
169 {
170 switch (expr->type) {
171 case EXPR_STRING:
172 return expr->string->length;
173 case EXPR_INITIALIZER: {
174 struct expression *tmp;
175 int i = 0;
176
177 FOR_EACH_PTR(expr->expr_list, tmp) {
178 if (tmp->type == EXPR_INDEX) {
179 if (tmp->idx_to >= i)
180 i = tmp->idx_to;
181 else
182 continue;
183 }
184
185 i++;
186 } END_FOR_EACH_PTR(tmp);
187 return i;
188 }
189 case EXPR_SYMBOL:
190 return get_array_size(expr);
191 }
192 return 0;
193 }
194
195 static struct range_list *db_size_rl;
db_size_callback(void * unused,int argc,char ** argv,char ** azColName)196 static int db_size_callback(void *unused, int argc, char **argv, char **azColName)
197 {
198 struct range_list *tmp = NULL;
199
200 if (!db_size_rl) {
201 str_to_rl(&int_ctype, argv[0], &db_size_rl);
202 } else {
203 str_to_rl(&int_ctype, argv[0], &tmp);
204 db_size_rl = rl_union(db_size_rl, tmp);
205 }
206 return 0;
207 }
208
size_from_db_type(struct expression * expr)209 static struct range_list *size_from_db_type(struct expression *expr)
210 {
211 int this_file_only = 0;
212 char *name;
213
214 name = get_member_name(expr);
215 if (!name && is_static(expr)) {
216 name = expr_to_var(expr);
217 this_file_only = 1;
218 }
219 if (!name)
220 return NULL;
221
222 if (this_file_only) {
223 db_size_rl = NULL;
224 run_sql(db_size_callback, NULL,
225 "select size from function_type_size where type = '%s' and file = '%s';",
226 name, get_filename());
227 if (db_size_rl)
228 return db_size_rl;
229 return NULL;
230 }
231
232 db_size_rl = NULL;
233 run_sql(db_size_callback, NULL,
234 "select size from type_size where type = '%s';",
235 name);
236 return db_size_rl;
237 }
238
size_from_db_symbol(struct expression * expr)239 static struct range_list *size_from_db_symbol(struct expression *expr)
240 {
241 struct symbol *sym;
242
243 if (expr->type != EXPR_SYMBOL)
244 return NULL;
245 sym = expr->symbol;
246 if (!sym || !sym->ident ||
247 !(sym->ctype.modifiers & MOD_TOPLEVEL) ||
248 sym->ctype.modifiers & MOD_STATIC)
249 return NULL;
250
251 db_size_rl = NULL;
252 run_sql(db_size_callback, NULL,
253 "select value from data_info where file = 'extern' and data = '%s' and type = %d;",
254 sym->ident->name, BUF_SIZE);
255 return db_size_rl;
256 }
257
size_from_db(struct expression * expr)258 static struct range_list *size_from_db(struct expression *expr)
259 {
260 struct range_list *rl;
261
262 rl = size_from_db_symbol(expr);
263 if (rl)
264 return rl;
265 return size_from_db_type(expr);
266 }
267
db_returns_buf_size(struct expression * expr,int param,char * unused,char * math)268 static void db_returns_buf_size(struct expression *expr, int param, char *unused, char *math)
269 {
270 struct expression *call;
271 struct range_list *rl;
272 sval_t sval;
273
274 if (expr->type != EXPR_ASSIGNMENT)
275 return;
276 call = strip_expr(expr->right);
277
278 call_results_to_rl(call, &int_ctype, math, &rl);
279 rl = cast_rl(&int_ctype, rl);
280 if (rl_to_sval(rl, &sval) && sval.value == 0)
281 return;
282 set_state_expr(my_size_id, expr->left, alloc_estate_rl(rl));
283 }
284
get_real_array_size_from_type(struct symbol * type)285 static int get_real_array_size_from_type(struct symbol *type)
286 {
287 sval_t sval;
288
289 if (!type)
290 return 0;
291 if (!type || type->type != SYM_ARRAY)
292 return 0;
293
294 if (!get_implied_value(type->array_size, &sval))
295 return 0;
296
297 return sval.value;
298 }
299
get_real_array_size(struct expression * expr)300 int get_real_array_size(struct expression *expr)
301 {
302 if (!expr)
303 return 0;
304 if (expr->type == EXPR_PREOP && expr->op == '&')
305 expr = expr->unop;
306 if (expr->type == EXPR_BINOP) /* array elements foo[5] */
307 return 0;
308 return get_real_array_size_from_type(get_type(expr));
309 }
310
get_size_from_initializer(struct expression * expr)311 static int get_size_from_initializer(struct expression *expr)
312 {
313 if (expr->type != EXPR_SYMBOL || !expr->symbol || !expr->symbol->initializer)
314 return 0;
315 if (expr->symbol->initializer == expr) /* int a = a; */
316 return 0;
317 return get_initializer_size(expr->symbol->initializer);
318 }
319
get_stored_size_bytes(struct expression * expr)320 static struct range_list *get_stored_size_bytes(struct expression *expr)
321 {
322 struct smatch_state *state;
323
324 state = get_state_expr(my_size_id, expr);
325 if (!state)
326 return NULL;
327 return estate_rl(state);
328 }
329
get_bytes_from_address(struct expression * expr)330 static int get_bytes_from_address(struct expression *expr)
331 {
332 struct symbol *type;
333 int ret;
334
335 if (expr->type != EXPR_PREOP || expr->op != '&')
336 return 0;
337 type = get_type(expr);
338 if (!type)
339 return 0;
340
341 if (type->type == SYM_PTR)
342 type = get_base_type(type);
343
344 ret = type_bytes(type);
345 if (ret == 1)
346 return 0; /* ignore char pointers */
347
348 return ret;
349 }
350
remove_addr_fluff(struct expression * expr)351 static struct expression *remove_addr_fluff(struct expression *expr)
352 {
353 struct expression *tmp;
354 sval_t sval;
355
356 expr = strip_expr(expr);
357
358 /* remove '&' and '*' operations that cancel */
359 while (expr && expr->type == EXPR_PREOP && expr->op == '&') {
360 tmp = strip_expr(expr->unop);
361 if (tmp->type != EXPR_PREOP)
362 break;
363 if (tmp->op != '*')
364 break;
365 expr = strip_expr(tmp->unop);
366 }
367
368 if (!expr)
369 return NULL;
370
371 /* "foo + 0" is just "foo" */
372 if (expr->type == EXPR_BINOP && expr->op == '+' &&
373 get_value(expr->right, &sval) && sval.value == 0)
374 return expr->left;
375
376 return expr;
377 }
378
is_last_member_of_struct(struct symbol * sym,struct ident * member)379 static int is_last_member_of_struct(struct symbol *sym, struct ident *member)
380 {
381 struct symbol *tmp;
382 int i;
383
384 i = 0;
385 FOR_EACH_PTR_REVERSE(sym->symbol_list, tmp) {
386 if (i++ || !tmp->ident)
387 return 0;
388 if (tmp->ident == member)
389 return 1;
390 return 0;
391 } END_FOR_EACH_PTR_REVERSE(tmp);
392
393 return 0;
394 }
395
last_member_is_resizable(struct symbol * sym)396 int last_member_is_resizable(struct symbol *sym)
397 {
398 struct symbol *last_member;
399 struct symbol *type;
400 sval_t sval;
401
402 if (!sym || sym->type != SYM_STRUCT)
403 return 0;
404
405 last_member = last_ptr_list((struct ptr_list *)sym->symbol_list);
406 if (!last_member || !last_member->ident)
407 return 0;
408
409 type = get_real_base_type(last_member);
410 if (type->type == SYM_STRUCT)
411 return last_member_is_resizable(type);
412 if (type->type != SYM_ARRAY)
413 return 0;
414
415 if (!get_implied_value(type->array_size, &sval))
416 return 0;
417
418 if (sval.value != 0 && sval.value != 1)
419 return 0;
420
421 return 1;
422 }
423
get_stored_size_end_struct_bytes(struct expression * expr)424 static int get_stored_size_end_struct_bytes(struct expression *expr)
425 {
426 struct symbol *sym;
427 struct symbol *base_sym;
428 struct smatch_state *state;
429
430 if (expr->type == EXPR_BINOP) /* array elements foo[5] */
431 return 0;
432
433 if (expr->type == EXPR_PREOP && expr->op == '&')
434 expr = strip_parens(expr->unop);
435
436 sym = expr_to_sym(expr);
437 if (!sym || !sym->ident)
438 return 0;
439 if (!type_bytes(sym))
440 return 0;
441 if (sym->type != SYM_NODE)
442 return 0;
443
444 base_sym = get_real_base_type(sym);
445 if (!base_sym || base_sym->type != SYM_PTR)
446 return 0;
447 base_sym = get_real_base_type(base_sym);
448 if (!base_sym || base_sym->type != SYM_STRUCT)
449 return 0;
450
451 if (!is_last_member_of_struct(base_sym, expr->member))
452 return 0;
453 if (!last_member_is_resizable(base_sym))
454 return 0;
455
456 state = get_state(my_size_id, sym->ident->name, sym);
457 if (!estate_to_size(state) || estate_to_size(state) == -1)
458 return 0;
459
460 return estate_to_size(state) - type_bytes(base_sym) + type_bytes(get_type(expr));
461 }
462
alloc_int_rl(int value)463 static struct range_list *alloc_int_rl(int value)
464 {
465 sval_t sval = {
466 .type = &int_ctype,
467 {.value = value},
468 };
469
470 return alloc_rl(sval, sval);
471 }
472
get_array_size_bytes_rl(struct expression * expr)473 struct range_list *get_array_size_bytes_rl(struct expression *expr)
474 {
475 struct range_list *ret = NULL;
476 sval_t sval;
477 int size;
478
479 expr = remove_addr_fluff(expr);
480 if (!expr)
481 return NULL;
482
483 /* "BAR" */
484 if (expr->type == EXPR_STRING)
485 return alloc_int_rl(expr->string->length);
486
487 if (expr->type == EXPR_BINOP && expr->op == '+') {
488 sval_t offset;
489 struct symbol *type;
490 int bytes;
491
492 if (!get_implied_value(expr->right, &offset))
493 return NULL;
494 type = get_type(expr->left);
495 if (!type)
496 return NULL;
497 if (type->type != SYM_ARRAY && type->type != SYM_PTR)
498 return NULL;
499 type = get_real_base_type(type);
500 bytes = type_bytes(type);
501 if (bytes == 0)
502 return NULL;
503 offset.value *= bytes;
504 size = get_array_size_bytes(expr->left);
505 if (size <= 0)
506 return NULL;
507 return alloc_int_rl(size - offset.value);
508 }
509
510 /* buf = malloc(1024); */
511 ret = get_stored_size_bytes(expr);
512 if (ret)
513 return ret;
514
515 size = get_stored_size_end_struct_bytes(expr);
516 if (size)
517 return alloc_int_rl(size);
518
519 /* buf[4] */
520 size = get_real_array_size(expr);
521 if (size)
522 return alloc_int_rl(elements_to_bytes(expr, size));
523
524 /* char *foo = "BAR" */
525 size = get_size_from_initializer(expr);
526 if (size)
527 return alloc_int_rl(elements_to_bytes(expr, size));
528
529 size = get_bytes_from_address(expr);
530 if (size)
531 return alloc_int_rl(size);
532
533 ret = size_from_db(expr);
534 if (rl_to_sval(ret, &sval) && sval.value == -1)
535 return NULL;
536 if (ret)
537 return ret;
538
539 return NULL;
540 }
541
get_array_size_bytes(struct expression * expr)542 int get_array_size_bytes(struct expression *expr)
543 {
544 struct range_list *rl;
545 sval_t sval;
546
547 rl = get_array_size_bytes_rl(expr);
548 if (!rl_to_sval(rl, &sval))
549 return 0;
550 if (sval.uvalue >= INT_MAX)
551 return 0;
552 return sval.value;
553 }
554
get_array_size_bytes_max(struct expression * expr)555 int get_array_size_bytes_max(struct expression *expr)
556 {
557 struct range_list *rl;
558 sval_t bytes;
559
560 rl = get_array_size_bytes_rl(expr);
561 if (!rl)
562 return 0;
563 bytes = rl_min(rl);
564 if (bytes.value < 0)
565 return 0;
566 bytes = rl_max(rl);
567 if (bytes.uvalue >= INT_MAX)
568 return 0;
569 return bytes.value;
570 }
571
get_array_size_bytes_min(struct expression * expr)572 int get_array_size_bytes_min(struct expression *expr)
573 {
574 struct range_list *rl;
575 struct data_range *range;
576
577 rl = get_array_size_bytes_rl(expr);
578 if (!rl)
579 return 0;
580
581 FOR_EACH_PTR(rl, range) {
582 if (range->min.value <= 0)
583 return 0;
584 if (range->max.value <= 0)
585 return 0;
586 if (range->min.uvalue >= INT_MAX)
587 return 0;
588 return range->min.value;
589 } END_FOR_EACH_PTR(range);
590
591 return 0;
592 }
593
get_array_size(struct expression * expr)594 int get_array_size(struct expression *expr)
595 {
596 if (!expr)
597 return 0;
598 return bytes_to_elements(expr, get_array_size_bytes_max(expr));
599 }
600
strip_ampersands(struct expression * expr)601 static struct expression *strip_ampersands(struct expression *expr)
602 {
603 struct symbol *type;
604
605 if (expr->type != EXPR_PREOP)
606 return expr;
607 if (expr->op != '&')
608 return expr;
609 type = get_type(expr->unop);
610 if (!type || type->type != SYM_ARRAY)
611 return expr;
612 return expr->unop;
613 }
614
info_record_alloction(struct expression * buffer,struct range_list * rl)615 static void info_record_alloction(struct expression *buffer, struct range_list *rl)
616 {
617 char *name;
618
619 if (!option_info)
620 return;
621
622 name = get_member_name(buffer);
623 if (!name && is_static(buffer))
624 name = expr_to_var(buffer);
625 if (!name)
626 return;
627 if (rl && !is_whole_rl(rl))
628 sql_insert_function_type_size(name, show_rl(rl));
629 else
630 sql_insert_function_type_size(name, "(-1)");
631
632 free_string(name);
633 }
634
store_alloc(struct expression * expr,struct range_list * rl)635 static void store_alloc(struct expression *expr, struct range_list *rl)
636 {
637 struct symbol *type;
638
639 rl = clone_rl(rl); // FIXME!!!
640 if (!rl)
641 rl = size_to_rl(UNKNOWN_SIZE);
642
643 if (rl_min(rl).value != UNKNOWN_SIZE ||
644 rl_max(rl).value != UNKNOWN_SIZE ||
645 get_state_expr(my_size_id, expr))
646 set_state_expr(my_size_id, expr, alloc_estate_rl(rl));
647
648 type = get_type(expr);
649 if (!type)
650 return;
651 if (type->type != SYM_PTR)
652 return;
653 type = get_real_base_type(type);
654 if (!type)
655 return;
656 if (type == &void_ctype)
657 return;
658 if (type->type != SYM_BASETYPE && type->type != SYM_PTR)
659 return;
660
661 info_record_alloction(expr, rl);
662 }
663
is_array_base(struct expression * expr)664 static bool is_array_base(struct expression *expr)
665 {
666 struct symbol *type;
667
668 type = get_type(expr);
669 if (type && type->type == SYM_ARRAY)
670 return true;
671 return false;
672 }
673
match_array_assignment(struct expression * expr)674 static void match_array_assignment(struct expression *expr)
675 {
676 struct expression *left;
677 struct expression *right;
678 char *left_member, *right_member;
679 struct range_list *rl;
680 sval_t sval;
681
682 if (expr->op != '=')
683 return;
684
685 left = strip_expr(expr->left);
686 right = strip_expr(expr->right);
687 right = strip_ampersands(right);
688
689 if (!is_pointer(left))
690 return;
691 /* char buf[24] = "str"; */
692 if (is_array_base(left))
693 return;
694 if (is_allocation_function(right))
695 return;
696
697 left_member = get_member_name(left);
698 right_member = get_member_name(right);
699 if (left_member && right_member && strcmp(left_member, right_member) == 0) {
700 free_string(left_member);
701 free_string(right_member);
702 return;
703 }
704 free_string(left_member);
705 free_string(right_member);
706
707 if (get_implied_value(right, &sval) && sval.value == 0) {
708 rl = alloc_int_rl(0);
709 goto store;
710 }
711
712 rl = get_array_size_bytes_rl(right);
713 if (!rl && __in_fake_assign)
714 return;
715
716 store:
717 store_alloc(left, rl);
718 }
719
match_alloc(const char * fn,struct expression * expr,void * _size_arg)720 static void match_alloc(const char *fn, struct expression *expr, void *_size_arg)
721 {
722 int size_arg = PTR_INT(_size_arg);
723 struct expression *right;
724 struct expression *arg;
725 struct range_list *rl;
726
727 right = strip_expr(expr->right);
728 arg = get_argument_from_call_expr(right->args, size_arg);
729 get_absolute_rl(arg, &rl);
730 rl = cast_rl(&int_ctype, rl);
731 store_alloc(expr->left, rl);
732 }
733
match_calloc(const char * fn,struct expression * expr,void * _param)734 static void match_calloc(const char *fn, struct expression *expr, void *_param)
735 {
736 struct expression *right;
737 struct expression *size, *nr, *mult;
738 struct range_list *rl;
739 int param = PTR_INT(_param);
740
741 right = strip_expr(expr->right);
742 nr = get_argument_from_call_expr(right->args, param);
743 size = get_argument_from_call_expr(right->args, param + 1);
744 mult = binop_expression(nr, '*', size);
745 if (get_implied_rl(mult, &rl))
746 store_alloc(expr->left, rl);
747 else
748 store_alloc(expr->left, size_to_rl(UNKNOWN_SIZE));
749 }
750
match_page(const char * fn,struct expression * expr,void * _unused)751 static void match_page(const char *fn, struct expression *expr, void *_unused)
752 {
753 sval_t page_size = {
754 .type = &int_ctype,
755 {.value = 4096},
756 };
757
758 store_alloc(expr->left, alloc_rl(page_size, page_size));
759 }
760
match_strndup(const char * fn,struct expression * expr,void * unused)761 static void match_strndup(const char *fn, struct expression *expr, void *unused)
762 {
763 struct expression *fn_expr;
764 struct expression *size_expr;
765 sval_t size;
766
767 fn_expr = strip_expr(expr->right);
768 size_expr = get_argument_from_call_expr(fn_expr->args, 1);
769 if (get_implied_max(size_expr, &size)) {
770 size.value++;
771 store_alloc(expr->left, size_to_rl(size.value));
772 } else {
773 store_alloc(expr->left, size_to_rl(UNKNOWN_SIZE));
774 }
775
776 }
777
match_alloc_pages(const char * fn,struct expression * expr,void * _order_arg)778 static void match_alloc_pages(const char *fn, struct expression *expr, void *_order_arg)
779 {
780 int order_arg = PTR_INT(_order_arg);
781 struct expression *right;
782 struct expression *arg;
783 sval_t sval;
784
785 right = strip_expr(expr->right);
786 arg = get_argument_from_call_expr(right->args, order_arg);
787 if (!get_implied_value(arg, &sval))
788 return;
789 if (sval.value < 0 || sval.value > 10)
790 return;
791
792 sval.type = &int_ctype;
793 sval.value = 1 << sval.value;
794 sval.value *= 4096;
795
796 store_alloc(expr->left, alloc_rl(sval, sval));
797 }
798
is_type_bytes(struct range_list * rl,struct expression * arg)799 static int is_type_bytes(struct range_list *rl, struct expression *arg)
800 {
801 struct symbol *type;
802 sval_t sval;
803
804 if (!rl_to_sval(rl, &sval))
805 return 0;
806
807 type = get_type(arg);
808 if (!type)
809 return 0;
810 if (type->type != SYM_PTR)
811 return 0;
812 type = get_real_base_type(type);
813 if (type->type != SYM_STRUCT &&
814 type->type != SYM_UNION)
815 return 0;
816 if (sval.value != type_bytes(type))
817 return 0;
818 return 1;
819 }
820
match_call(struct expression * expr)821 static void match_call(struct expression *expr)
822 {
823 struct expression *arg;
824 struct symbol *type;
825 struct range_list *rl;
826 int i;
827
828 i = -1;
829 FOR_EACH_PTR(expr->args, arg) {
830 i++;
831 type = get_type(arg);
832 if (!type || (type->type != SYM_PTR && type->type != SYM_ARRAY))
833 continue;
834 rl = get_array_size_bytes_rl(arg);
835 if (!rl)
836 continue;
837 if (rl_min(rl).value == UNKNOWN_SIZE &&
838 rl_max(rl).value == UNKNOWN_SIZE)
839 continue;
840 if (is_whole_rl(rl))
841 continue;
842 if (is_type_bytes(rl, arg))
843 continue;
844 sql_insert_caller_info(expr, BUF_SIZE, i, "$", show_rl(rl));
845 } END_FOR_EACH_PTR(arg);
846 }
847
struct_member_callback(struct expression * call,int param,char * printed_name,struct sm_state * sm)848 static void struct_member_callback(struct expression *call, int param, char *printed_name, struct sm_state *sm)
849 {
850 sval_t sval;
851
852 if (!estate_rl(sm->state) ||
853 (estate_get_single_value(sm->state, &sval) &&
854 (sval.value == -1 || sval.value == 0)))
855 return;
856
857 sql_insert_caller_info(call, BUF_SIZE, param, printed_name, sm->state->name);
858 }
859
860 /*
861 * This is slightly (very) weird because half of this stuff is handled in
862 * smatch_parse_call_math.c which is poorly named. But anyway, add some buf
863 * sizes here.
864 *
865 */
print_returned_allocations(int return_id,char * return_ranges,struct expression * expr)866 static void print_returned_allocations(int return_id, char *return_ranges, struct expression *expr)
867 {
868 const char *param_math;
869 struct range_list *rl;
870 char buf[64];
871 sval_t sval;
872
873 rl = get_array_size_bytes_rl(expr);
874 param_math = get_allocation_math(expr);
875 if (!rl && !param_math)
876 return;
877
878 if (!param_math &&
879 rl_to_sval(rl, &sval) &&
880 (sval.value == -1 || sval.value == 0))
881 return;
882
883 if (param_math)
884 snprintf(buf, sizeof(buf), "%s[%s]", show_rl(rl), param_math);
885 else
886 snprintf(buf, sizeof(buf), "%s", show_rl(rl));
887
888 // FIXME: don't store if you can guess the size from the type
889 // FIXME: return if we allocate a parameter $0->bar
890 sql_insert_return_states(return_id, return_ranges, BUF_SIZE, -1, "", buf);
891 }
892
record_global_size(struct symbol * sym)893 static void record_global_size(struct symbol *sym)
894 {
895 int bytes;
896 char buf[16];
897
898 if (!sym->ident)
899 return;
900
901 if (!(sym->ctype.modifiers & MOD_TOPLEVEL) ||
902 sym->ctype.modifiers & MOD_STATIC)
903 return;
904
905 bytes = get_array_size_bytes(symbol_expression(sym));
906 if (bytes <= 1)
907 return;
908
909 snprintf(buf, sizeof(buf), "%d", bytes);
910 sql_insert_data_info_var_sym(sym->ident->name, sym, BUF_SIZE, buf);
911 }
912
register_buf_size(int id)913 void register_buf_size(int id)
914 {
915 my_size_id = id;
916
917 set_dynamic_states(my_size_id);
918
919 add_unmatched_state_hook(my_size_id, &unmatched_size_state);
920 add_merge_hook(my_size_id, &merge_estates);
921
922 select_caller_info_hook(set_param_buf_size, BUF_SIZE);
923 select_return_states_hook(BUF_SIZE, &db_returns_buf_size);
924 add_split_return_callback(print_returned_allocations);
925
926 allocation_funcs = create_function_hashtable(100);
927 add_allocation_function("malloc", &match_alloc, 0);
928 add_allocation_function("calloc", &match_calloc, 0);
929 add_allocation_function("memdup", &match_alloc, 1);
930 add_allocation_function("realloc", &match_alloc, 1);
931 if (option_project == PROJ_KERNEL) {
932 add_allocation_function("kmalloc", &match_alloc, 0);
933 add_allocation_function("kmalloc_node", &match_alloc, 0);
934 add_allocation_function("kzalloc", &match_alloc, 0);
935 add_allocation_function("kzalloc_node", &match_alloc, 0);
936 add_allocation_function("vmalloc", &match_alloc, 0);
937 add_allocation_function("vzalloc", &match_alloc, 0);
938 add_allocation_function("__vmalloc", &match_alloc, 0);
939 add_allocation_function("kvmalloc", &match_alloc, 0);
940 add_allocation_function("kcalloc", &match_calloc, 0);
941 add_allocation_function("kmalloc_array", &match_calloc, 0);
942 add_allocation_function("devm_kmalloc_array", &match_calloc, 1);
943 add_allocation_function("sock_kmalloc", &match_alloc, 1);
944 add_allocation_function("kmemdup", &match_alloc, 1);
945 add_allocation_function("kmemdup_user", &match_alloc, 1);
946 add_allocation_function("dma_alloc_attrs", &match_alloc, 1);
947 add_allocation_function("pci_alloc_consistent", &match_alloc, 1);
948 add_allocation_function("pci_alloc_coherent", &match_alloc, 1);
949 add_allocation_function("devm_kmalloc", &match_alloc, 1);
950 add_allocation_function("devm_kzalloc", &match_alloc, 1);
951 add_allocation_function("krealloc", &match_alloc, 1);
952 add_allocation_function("__alloc_bootmem", &match_alloc, 0);
953 add_allocation_function("alloc_bootmem", &match_alloc, 0);
954 add_allocation_function("kmap", &match_page, 0);
955 add_allocation_function("kmap_atomic", &match_page, 0);
956 add_allocation_function("get_zeroed_page", &match_page, 0);
957 add_allocation_function("alloc_page", &match_page, 0);
958 add_allocation_function("alloc_pages", &match_alloc_pages, 1);
959 add_allocation_function("alloc_pages_current", &match_alloc_pages, 1);
960 add_allocation_function("__get_free_pages", &match_alloc_pages, 1);
961 add_allocation_function("dma_alloc_contiguous", &match_alloc, 1);
962 add_allocation_function("dma_alloc_coherent", &match_alloc, 1);
963 }
964
965 add_allocation_function("strndup", match_strndup, 0);
966 if (option_project == PROJ_KERNEL)
967 add_allocation_function("kstrndup", match_strndup, 0);
968
969 add_modification_hook(my_size_id, &set_size_undefined);
970
971 add_merge_hook(my_size_id, &merge_size_func);
972
973 if (option_info)
974 add_hook(record_global_size, BASE_HOOK);
975 }
976
register_buf_size_late(int id)977 void register_buf_size_late(int id)
978 {
979 /* has to happen after match_alloc() */
980 add_hook(&match_array_assignment, ASSIGNMENT_HOOK);
981
982 add_hook(&match_call, FUNCTION_CALL_HOOK);
983 add_member_info_callback(my_size_id, struct_member_callback);
984 }
985