1 /*
2 * Copyright (C) 2009 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 /*
19 * This script is for finding functions like hcd_buffer_free() which free
20 * their arguments. After running it, add those functions to check_memory.c
21 */
22
23 #include "smatch.h"
24 #include "smatch_slist.h"
25
26 static int my_id;
27
28 STATE(putted);
29
30 static struct symbol *this_func;
31 static struct tracker_list *putted_args = NULL;
32
match_function_def(struct symbol * sym)33 static void match_function_def(struct symbol *sym)
34 {
35 this_func = sym;
36 }
37
parent_is_arg(struct symbol * sym)38 static int parent_is_arg(struct symbol *sym)
39 {
40 struct symbol *arg;
41
42 FOR_EACH_PTR(this_func->ctype.base_type->arguments, arg) {
43 if (sym == arg)
44 return 1;
45 } END_FOR_EACH_PTR(arg);
46 return 0;
47 }
48
match_put(const char * fn,struct expression * expr,void * info)49 static void match_put(const char *fn, struct expression *expr, void *info)
50 {
51 struct expression *tmp;
52 struct symbol *sym;
53 char *name;
54
55 tmp = get_argument_from_call_expr(expr->args, 0);
56 tmp = strip_expr(tmp);
57 name = expr_to_var_sym(tmp, &sym);
58 free_string(name);
59 if (parent_is_arg(sym) && sym->ident)
60 set_state(my_id, sym->ident->name, sym, &putted);
61 }
62
63 static int return_count = 0;
match_return(struct expression * ret_value)64 static void match_return(struct expression *ret_value)
65 {
66 struct stree *stree;
67 struct sm_state *tmp;
68 struct tracker *tracker;
69
70 if (__inline_fn)
71 return;
72
73 if (!return_count) {
74 stree = __get_cur_stree();
75 FOR_EACH_MY_SM(my_id, stree, tmp) {
76 if (tmp->state == &putted)
77 add_tracker(&putted_args, my_id, tmp->name,
78 tmp->sym);
79 } END_FOR_EACH_SM(tmp);
80 } else {
81 FOR_EACH_PTR(putted_args, tracker) {
82 tmp = get_sm_state(my_id, tracker->name, tracker->sym);
83 if (tmp && tmp->state != &putted)
84 del_tracker(&putted_args, my_id, tracker->name,
85 tracker->sym);
86 } END_FOR_EACH_PTR(tracker);
87
88 }
89 }
90
print_arg(struct symbol * sym)91 static void print_arg(struct symbol *sym)
92 {
93 struct symbol *arg;
94 int i = 0;
95
96 FOR_EACH_PTR(this_func->ctype.base_type->arguments, arg) {
97 if (sym == arg) {
98 sm_info("puts_arg %s %d", get_function(), i);
99 return;
100 }
101 i++;
102 } END_FOR_EACH_PTR(arg);
103 }
104
match_end_func(struct symbol * sym)105 static void match_end_func(struct symbol *sym)
106 {
107 struct tracker *tracker;
108
109 if (__inline_fn)
110 return;
111 if (is_reachable())
112 match_return(NULL);
113
114 FOR_EACH_PTR(putted_args, tracker) {
115 print_arg(tracker->sym);
116 } END_FOR_EACH_PTR(tracker);
117
118 free_trackers_and_list(&putted_args);
119 return_count = 0;
120 }
121
check_puts_argument(int id)122 void check_puts_argument(int id)
123 {
124 if (!option_info || option_project != PROJ_KERNEL)
125 return;
126
127 my_id = id;
128 add_hook(&match_function_def, FUNC_DEF_HOOK);
129 add_function_hook("kobject_put", &match_put, NULL);
130 add_function_hook("kref_put", &match_put, NULL);
131 add_hook(&match_return, RETURN_HOOK);
132 add_hook(&match_end_func, END_FUNC_HOOK);
133 }
134