2 * Copyright (C) 2010 Dan Carpenter.
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.
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.
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
22 #include "smatch_slist.h"
23 #include "smatch_extra.h"
24 #include "smatch_function_hashtable.h"
26 #define UNKNOWN_SIZE (-1)
28 static int my_size_id
;
30 static DEFINE_HASHTABLE_INSERT(insert_func
, char, int);
31 static DEFINE_HASHTABLE_SEARCH(search_func
, char, int);
32 static struct hashtable
*allocation_funcs
;
34 static char *get_fn_name(struct expression
*expr
)
36 if (expr
->type
!= EXPR_CALL
)
38 if (expr
->fn
->type
!= EXPR_SYMBOL
)
40 return expr_to_var(expr
->fn
);
43 static int is_allocation_function(struct expression
*expr
)
48 func
= get_fn_name(expr
);
51 if (search_func(allocation_funcs
, func
))
57 static void add_allocation_function(const char *func
, void *call_back
, int param
)
59 insert_func(allocation_funcs
, (char *)func
, (int *)1);
60 add_function_assign_hook(func
, call_back
, INT_PTR(param
));
63 static int estate_to_size(struct smatch_state
*state
)
67 if (!state
|| !estate_rl(state
))
69 sval
= estate_max(state
);
73 static struct smatch_state
*size_to_estate(int size
)
77 sval
.type
= &int_ctype
;
80 return alloc_estate_sval(sval
);
83 static struct range_list
*size_to_rl(int size
)
87 sval
.type
= &int_ctype
;
90 return alloc_rl(sval
, sval
);
93 static struct smatch_state
*unmatched_size_state(struct sm_state
*sm
)
95 return size_to_estate(UNKNOWN_SIZE
);
98 static void set_size_undefined(struct sm_state
*sm
, struct expression
*mod_expr
)
100 set_state(sm
->owner
, sm
->name
, sm
->sym
, size_to_estate(UNKNOWN_SIZE
));
103 static struct smatch_state
*merge_size_func(struct smatch_state
*s1
, struct smatch_state
*s2
)
105 return merge_estates(s1
, s2
);
108 void set_param_buf_size(const char *name
, struct symbol
*sym
, char *key
, char *value
)
110 struct range_list
*rl
= NULL
;
111 struct smatch_state
*state
;
114 if (strncmp(key
, "$", 1) != 0)
117 snprintf(fullname
, 256, "%s%s", name
, key
+ 1);
119 str_to_rl(&int_ctype
, value
, &rl
);
120 if (!rl
|| is_whole_rl(rl
))
122 state
= alloc_estate_rl(rl
);
123 set_state(my_size_id
, fullname
, sym
, state
);
126 static int bytes_per_element(struct expression
*expr
)
132 if (expr
->type
== EXPR_STRING
)
134 if (expr
->type
== EXPR_PREOP
&& expr
->op
== '&') {
135 type
= get_type(expr
->unop
);
136 if (type
&& type
->type
== SYM_ARRAY
)
139 type
= get_type(expr
);
143 if (type
->type
!= SYM_PTR
&& type
->type
!= SYM_ARRAY
)
146 type
= get_base_type(type
);
147 return type_bytes(type
);
150 static int bytes_to_elements(struct expression
*expr
, int bytes
)
154 bpe
= bytes_per_element(expr
);
160 static int elements_to_bytes(struct expression
*expr
, int elements
)
164 bpe
= bytes_per_element(expr
);
165 return elements
* bpe
;
168 static int get_initializer_size(struct expression
*expr
)
170 switch (expr
->type
) {
172 return expr
->string
->length
;
173 case EXPR_INITIALIZER
: {
174 struct expression
*tmp
;
177 FOR_EACH_PTR(expr
->expr_list
, tmp
) {
178 if (tmp
->type
== EXPR_INDEX
) {
179 if (tmp
->idx_to
>= i
)
186 } END_FOR_EACH_PTR(tmp
);
190 return get_array_size(expr
);
195 static struct range_list
*db_size_rl
;
196 static int db_size_callback(void *unused
, int argc
, char **argv
, char **azColName
)
198 struct range_list
*tmp
= NULL
;
201 str_to_rl(&int_ctype
, argv
[0], &db_size_rl
);
203 str_to_rl(&int_ctype
, argv
[0], &tmp
);
204 db_size_rl
= rl_union(db_size_rl
, tmp
);
209 static struct range_list
*size_from_db_type(struct expression
*expr
)
211 int this_file_only
= 0;
214 name
= get_member_name(expr
);
215 if (!name
&& is_static(expr
)) {
216 name
= expr_to_var(expr
);
222 if (this_file_only
) {
224 run_sql(db_size_callback
, NULL
,
225 "select size from function_type_size where type = '%s' and file = '%s';",
226 name
, get_filename());
233 run_sql(db_size_callback
, NULL
,
234 "select size from type_size where type = '%s';",
239 static struct range_list
*size_from_db_symbol(struct expression
*expr
)
243 if (expr
->type
!= EXPR_SYMBOL
)
246 if (!sym
|| !sym
->ident
||
247 !(sym
->ctype
.modifiers
& MOD_TOPLEVEL
) ||
248 sym
->ctype
.modifiers
& MOD_STATIC
)
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
);
258 static struct range_list
*size_from_db(struct expression
*expr
)
260 struct range_list
*rl
;
262 rl
= size_from_db_symbol(expr
);
265 return size_from_db_type(expr
);
268 static void db_returns_buf_size(struct expression
*expr
, int param
, char *unused
, char *math
)
270 struct expression
*call
;
271 struct range_list
*rl
;
273 if (expr
->type
!= EXPR_ASSIGNMENT
)
275 call
= strip_expr(expr
->right
);
277 if (!parse_call_math_rl(call
, math
, &rl
))
279 rl
= cast_rl(&int_ctype
, rl
);
280 set_state_expr(my_size_id
, expr
->left
, alloc_estate_rl(rl
));
283 static int get_real_array_size_from_type(struct symbol
*type
)
289 if (!type
|| type
->type
!= SYM_ARRAY
)
292 if (!get_implied_value(type
->array_size
, &sval
))
298 int get_real_array_size(struct expression
*expr
)
302 if (expr
->type
== EXPR_PREOP
&& expr
->op
== '&')
304 if (expr
->type
== EXPR_BINOP
) /* array elements foo[5] */
306 return get_real_array_size_from_type(get_type(expr
));
309 static int get_size_from_initializer(struct expression
*expr
)
311 if (expr
->type
!= EXPR_SYMBOL
|| !expr
->symbol
|| !expr
->symbol
->initializer
)
313 if (expr
->symbol
->initializer
== expr
) /* int a = a; */
315 return get_initializer_size(expr
->symbol
->initializer
);
318 static struct range_list
*get_stored_size_bytes(struct expression
*expr
)
320 struct smatch_state
*state
;
322 state
= get_state_expr(my_size_id
, expr
);
325 return estate_rl(state
);
328 static int get_bytes_from_address(struct expression
*expr
)
335 if (expr
->type
!= EXPR_PREOP
|| expr
->op
!= '&')
337 type
= get_type(expr
);
341 if (type
->type
== SYM_PTR
)
342 type
= get_base_type(type
);
344 ret
= type_bytes(type
);
346 return 0; /* ignore char pointers */
351 static struct expression
*remove_addr_fluff(struct expression
*expr
)
353 struct expression
*tmp
;
356 expr
= strip_expr(expr
);
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
)
365 expr
= strip_expr(tmp
->unop
);
371 /* "foo + 0" is just "foo" */
372 if (expr
->type
== EXPR_BINOP
&& expr
->op
== '+' &&
373 get_value(expr
->right
, &sval
) && sval
.value
== 0)
379 static int is_last_member_of_struct(struct symbol
*sym
, struct ident
*member
)
385 FOR_EACH_PTR_REVERSE(sym
->symbol_list
, tmp
) {
386 if (i
++ || !tmp
->ident
)
388 if (tmp
->ident
== member
)
391 } END_FOR_EACH_PTR_REVERSE(tmp
);
396 int last_member_is_resizable(struct symbol
*sym
)
398 struct symbol
*last_member
;
402 if (!sym
|| sym
->type
!= SYM_STRUCT
)
405 last_member
= last_ptr_list((struct ptr_list
*)sym
->symbol_list
);
406 if (!last_member
|| !last_member
->ident
)
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
)
415 if (!get_implied_value(type
->array_size
, &sval
))
418 if (sval
.value
!= 0 && sval
.value
!= 1)
424 static int get_stored_size_end_struct_bytes(struct expression
*expr
)
427 struct symbol
*base_sym
;
428 struct smatch_state
*state
;
430 if (expr
->type
== EXPR_BINOP
) /* array elements foo[5] */
433 if (expr
->type
== EXPR_PREOP
&& expr
->op
== '&')
434 expr
= strip_parens(expr
->unop
);
436 sym
= expr_to_sym(expr
);
437 if (!sym
|| !sym
->ident
)
439 if (!type_bytes(sym
))
441 if (sym
->type
!= SYM_NODE
)
444 base_sym
= get_real_base_type(sym
);
445 if (!base_sym
|| base_sym
->type
!= SYM_PTR
)
447 base_sym
= get_real_base_type(base_sym
);
448 if (!base_sym
|| base_sym
->type
!= SYM_STRUCT
)
451 if (!is_last_member_of_struct(base_sym
, expr
->member
))
453 if (!last_member_is_resizable(base_sym
))
456 state
= get_state(my_size_id
, sym
->ident
->name
, sym
);
457 if (!estate_to_size(state
))
460 return estate_to_size(state
) - type_bytes(base_sym
) + type_bytes(get_type(expr
));
463 static struct range_list
*alloc_int_rl(int value
)
470 return alloc_rl(sval
, sval
);
473 struct range_list
*get_array_size_bytes_rl(struct expression
*expr
)
475 struct range_list
*ret
= NULL
;
478 expr
= remove_addr_fluff(expr
);
483 if (expr
->type
== EXPR_STRING
)
484 return alloc_int_rl(expr
->string
->length
);
486 if (expr
->type
== EXPR_BINOP
&& expr
->op
== '+') {
491 if (!get_implied_value(expr
->right
, &offset
))
493 type
= get_type(expr
->left
);
496 if (type
->type
!= SYM_ARRAY
&& type
->type
!= SYM_PTR
)
498 type
= get_real_base_type(type
);
499 bytes
= type_bytes(type
);
502 offset
.value
*= bytes
;
503 size
= get_array_size_bytes(expr
->left
);
506 return alloc_int_rl(size
- offset
.value
);
510 size
= get_real_array_size(expr
);
512 return alloc_int_rl(elements_to_bytes(expr
, size
));
514 /* buf = malloc(1024); */
515 ret
= get_stored_size_bytes(expr
);
519 size
= get_stored_size_end_struct_bytes(expr
);
521 return alloc_int_rl(size
);
523 /* char *foo = "BAR" */
524 size
= get_size_from_initializer(expr
);
526 return alloc_int_rl(elements_to_bytes(expr
, size
));
528 size
= get_bytes_from_address(expr
);
530 return alloc_int_rl(size
);
532 ret
= size_from_db(expr
);
539 int get_array_size_bytes(struct expression
*expr
)
541 struct range_list
*rl
;
544 rl
= get_array_size_bytes_rl(expr
);
545 if (!rl_to_sval(rl
, &sval
))
547 if (sval
.uvalue
>= INT_MAX
)
552 int get_array_size_bytes_max(struct expression
*expr
)
554 struct range_list
*rl
;
557 rl
= get_array_size_bytes_rl(expr
);
564 if (bytes
.uvalue
>= INT_MAX
)
569 int get_array_size_bytes_min(struct expression
*expr
)
571 struct range_list
*rl
;
572 struct data_range
*range
;
574 rl
= get_array_size_bytes_rl(expr
);
578 FOR_EACH_PTR(rl
, range
) {
579 if (range
->min
.value
<= 0)
581 if (range
->max
.value
<= 0)
583 if (range
->min
.uvalue
>= INT_MAX
)
585 return range
->min
.value
;
586 } END_FOR_EACH_PTR(range
);
591 int get_array_size(struct expression
*expr
)
595 return bytes_to_elements(expr
, get_array_size_bytes_max(expr
));
598 static struct expression
*strip_ampersands(struct expression
*expr
)
602 if (expr
->type
!= EXPR_PREOP
)
606 type
= get_type(expr
->unop
);
607 if (!type
|| type
->type
!= SYM_ARRAY
)
612 static void info_record_alloction(struct expression
*buffer
, struct range_list
*rl
)
619 name
= get_member_name(buffer
);
620 if (!name
&& is_static(buffer
))
621 name
= expr_to_var(buffer
);
624 if (rl
&& !is_whole_rl(rl
))
625 sql_insert_function_type_size(name
, show_rl(rl
));
627 sql_insert_function_type_size(name
, "(-1)");
632 static void store_alloc(struct expression
*expr
, struct range_list
*rl
)
636 rl
= clone_rl(rl
); // FIXME!!!
637 set_state_expr(my_size_id
, expr
, alloc_estate_rl(rl
));
639 type
= get_type(expr
);
642 if (type
->type
!= SYM_PTR
)
644 type
= get_real_base_type(type
);
647 if (type
== &void_ctype
)
649 if (type
->type
!= SYM_BASETYPE
&& type
->type
!= SYM_PTR
)
652 info_record_alloction(expr
, rl
);
655 static void match_array_assignment(struct expression
*expr
)
657 struct expression
*left
;
658 struct expression
*right
;
659 char *left_member
, *right_member
;
660 struct range_list
*rl
;
665 left
= strip_expr(expr
->left
);
666 right
= strip_expr(expr
->right
);
667 right
= strip_ampersands(right
);
669 if (!is_pointer(left
))
671 if (is_allocation_function(right
))
674 left_member
= get_member_name(left
);
675 right_member
= get_member_name(right
);
676 if (left_member
&& right_member
&& strcmp(left_member
, right_member
) == 0) {
677 free_string(left_member
);
678 free_string(right_member
);
681 free_string(left_member
);
682 free_string(right_member
);
684 if (get_implied_value(right
, &sval
) && sval
.value
== 0) {
685 rl
= alloc_int_rl(0);
689 rl
= get_array_size_bytes_rl(right
);
690 if (!rl
&& __in_fake_assign
)
694 store_alloc(left
, rl
);
697 static void match_alloc(const char *fn
, struct expression
*expr
, void *_size_arg
)
699 int size_arg
= PTR_INT(_size_arg
);
700 struct expression
*right
;
701 struct expression
*arg
;
702 struct range_list
*rl
;
704 right
= strip_expr(expr
->right
);
705 arg
= get_argument_from_call_expr(right
->args
, size_arg
);
706 get_absolute_rl(arg
, &rl
);
707 rl
= cast_rl(&int_ctype
, rl
);
708 store_alloc(expr
->left
, rl
);
711 static void match_calloc(const char *fn
, struct expression
*expr
, void *unused
)
713 struct expression
*right
;
714 struct expression
*arg
;
718 right
= strip_expr(expr
->right
);
719 arg
= get_argument_from_call_expr(right
->args
, 0);
720 if (!get_implied_value(arg
, &elements
))
722 arg
= get_argument_from_call_expr(right
->args
, 1);
723 if (get_implied_value(arg
, &size
))
724 store_alloc(expr
->left
, size_to_rl(elements
.value
* size
.value
));
726 store_alloc(expr
->left
, size_to_rl(-1));
729 static void match_page(const char *fn
, struct expression
*expr
, void *_unused
)
736 store_alloc(expr
->left
, alloc_rl(page_size
, page_size
));
739 static void match_strndup(const char *fn
, struct expression
*expr
, void *unused
)
741 struct expression
*fn_expr
;
742 struct expression
*size_expr
;
745 fn_expr
= strip_expr(expr
->right
);
746 size_expr
= get_argument_from_call_expr(fn_expr
->args
, 1);
747 if (get_implied_max(size_expr
, &size
)) {
749 store_alloc(expr
->left
, size_to_rl(size
.value
));
751 store_alloc(expr
->left
, size_to_rl(-1));
756 static void match_alloc_pages(const char *fn
, struct expression
*expr
, void *_order_arg
)
758 int order_arg
= PTR_INT(_order_arg
);
759 struct expression
*right
;
760 struct expression
*arg
;
763 right
= strip_expr(expr
->right
);
764 arg
= get_argument_from_call_expr(right
->args
, order_arg
);
765 if (!get_implied_value(arg
, &sval
))
767 if (sval
.value
< 0 || sval
.value
> 10)
770 sval
.type
= &int_ctype
;
771 sval
.value
= 1 << sval
.value
;
774 store_alloc(expr
->left
, alloc_rl(sval
, sval
));
777 static int is_type_bytes(struct range_list
*rl
, struct expression
*arg
)
782 if (!rl_to_sval(rl
, &sval
))
785 type
= get_type(arg
);
788 if (type
->type
!= SYM_PTR
)
790 type
= get_real_base_type(type
);
791 if (type
->type
!= SYM_STRUCT
&&
792 type
->type
!= SYM_UNION
)
794 if (sval
.value
!= type_bytes(type
))
799 static void match_call(struct expression
*expr
)
801 struct expression
*arg
;
803 struct range_list
*rl
;
807 FOR_EACH_PTR(expr
->args
, arg
) {
809 type
= get_type(arg
);
810 if (!type
|| (type
->type
!= SYM_PTR
&& type
->type
!= SYM_ARRAY
))
812 rl
= get_array_size_bytes_rl(arg
);
817 if (is_type_bytes(rl
, arg
))
819 sql_insert_caller_info(expr
, BUF_SIZE
, i
, "$", show_rl(rl
));
820 } END_FOR_EACH_PTR(arg
);
823 static void struct_member_callback(struct expression
*call
, int param
, char *printed_name
, struct sm_state
*sm
)
825 if (sm
->state
== &merged
||
826 strcmp(sm
->state
->name
, "(-1)") == 0 ||
827 strcmp(sm
->state
->name
, "empty") == 0 ||
828 strcmp(sm
->state
->name
, "0") == 0)
830 sql_insert_caller_info(call
, BUF_SIZE
, param
, printed_name
, sm
->state
->name
);
834 * This is slightly (very) weird because half of this stuff is handled in
835 * smatch_parse_call_math.c which is poorly named. But anyway, add some buf
839 static void print_returned_allocations(int return_id
, char *return_ranges
, struct expression
*expr
)
844 size
= get_array_size_bytes(expr
);
848 snprintf(buf
, sizeof(buf
), "%d", size
);
849 sql_insert_return_states(return_id
, return_ranges
, BUF_SIZE
, -1, "", buf
);
852 static void record_global_size(struct symbol
*sym
)
860 if (!(sym
->ctype
.modifiers
& MOD_TOPLEVEL
) ||
861 sym
->ctype
.modifiers
& MOD_STATIC
)
864 bytes
= get_array_size_bytes(symbol_expression(sym
));
868 snprintf(buf
, sizeof(buf
), "%d", bytes
);
869 sql_insert_data_info_var_sym(sym
->ident
->name
, sym
, BUF_SIZE
, buf
);
872 void register_buf_size(int id
)
876 add_unmatched_state_hook(my_size_id
, &unmatched_size_state
);
878 select_caller_info_hook(set_param_buf_size
, BUF_SIZE
);
879 select_return_states_hook(BUF_SIZE
, &db_returns_buf_size
);
880 add_split_return_callback(print_returned_allocations
);
882 allocation_funcs
= create_function_hashtable(100);
883 add_allocation_function("malloc", &match_alloc
, 0);
884 add_allocation_function("calloc", &match_calloc
, 0);
885 add_allocation_function("memdup", &match_alloc
, 1);
886 add_allocation_function("realloc", &match_alloc
, 1);
887 if (option_project
== PROJ_KERNEL
) {
888 add_allocation_function("kmalloc", &match_alloc
, 0);
889 add_allocation_function("kmalloc_node", &match_alloc
, 0);
890 add_allocation_function("kzalloc", &match_alloc
, 0);
891 add_allocation_function("kzalloc_node", &match_alloc
, 0);
892 add_allocation_function("vmalloc", &match_alloc
, 0);
893 add_allocation_function("__vmalloc", &match_alloc
, 0);
894 add_allocation_function("kcalloc", &match_calloc
, 0);
895 add_allocation_function("kmalloc_array", &match_calloc
, 0);
896 add_allocation_function("drm_malloc_ab", &match_calloc
, 0);
897 add_allocation_function("drm_calloc_large", &match_calloc
, 0);
898 add_allocation_function("sock_kmalloc", &match_alloc
, 1);
899 add_allocation_function("kmemdup", &match_alloc
, 1);
900 add_allocation_function("kmemdup_user", &match_alloc
, 1);
901 add_allocation_function("dma_alloc_attrs", &match_alloc
, 1);
902 add_allocation_function("pci_alloc_consistent", &match_alloc
, 1);
903 add_allocation_function("pci_alloc_coherent", &match_alloc
, 1);
904 add_allocation_function("devm_kmalloc", &match_alloc
, 1);
905 add_allocation_function("devm_kzalloc", &match_alloc
, 1);
906 add_allocation_function("krealloc", &match_alloc
, 1);
907 add_allocation_function("__alloc_bootmem", &match_alloc
, 0);
908 add_allocation_function("alloc_bootmem", &match_alloc
, 0);
909 add_allocation_function("kmap", &match_page
, 0);
910 add_allocation_function("get_zeroed_page", &match_page
, 0);
911 add_allocation_function("alloc_pages", &match_alloc_pages
, 1);
912 add_allocation_function("alloc_pages_current", &match_alloc_pages
, 1);
913 add_allocation_function("__get_free_pages", &match_alloc_pages
, 1);
916 add_allocation_function("strndup", match_strndup
, 0);
917 if (option_project
== PROJ_KERNEL
)
918 add_allocation_function("kstrndup", match_strndup
, 0);
920 add_modification_hook(my_size_id
, &set_size_undefined
);
922 add_merge_hook(my_size_id
, &merge_size_func
);
925 add_hook(record_global_size
, BASE_HOOK
);
928 void register_buf_size_late(int id
)
930 /* has to happen after match_alloc() */
931 add_hook(&match_array_assignment
, ASSIGNMENT_HOOK
);
933 add_hook(&match_call
, FUNCTION_CALL_HOOK
);
934 add_member_info_callback(my_size_id
, struct_member_callback
);