1 /*
2 * Copyright (C) 2013 Oracle.
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 "smatch.h"
19
20 STATE(devm);
21
22 static int my_id;
23
match_assign(const char * fn,struct expression * expr,void * unused)24 static void match_assign(const char *fn, struct expression *expr, void *unused)
25 {
26 set_state_expr(my_id, expr->left, &devm);
27 }
28
match_free_func(const char * fn,struct expression * expr,void * _arg)29 static void match_free_func(const char *fn, struct expression *expr, void *_arg)
30 {
31 struct expression *arg_expr;
32 int arg = PTR_INT(_arg);
33 char *name;
34
35 arg_expr = get_argument_from_call_expr(expr->args, arg);
36 if (!get_state_expr(my_id, arg_expr))
37 return;
38 name = expr_to_str(arg_expr);
39 sm_warning("passing devm_ allocated variable to kfree. '%s'", name);
40 free_string(name);
41 }
42
register_funcs_from_file(void)43 static void register_funcs_from_file(void)
44 {
45 struct token *token;
46 const char *func;
47 int arg;
48
49 token = get_tokens_file("kernel.frees_argument");
50 if (!token)
51 return;
52 if (token_type(token) != TOKEN_STREAMBEGIN)
53 return;
54 token = token->next;
55 while (token_type(token) != TOKEN_STREAMEND) {
56 if (token_type(token) != TOKEN_IDENT)
57 return;
58 func = show_ident(token->ident);
59 token = token->next;
60 if (token_type(token) != TOKEN_NUMBER)
61 return;
62 arg = atoi(token->number);
63 add_function_hook(func, &match_free_func, INT_PTR(arg));
64 token = token->next;
65 }
66 clear_token_alloc();
67 }
68
check_freeing_devm(int id)69 void check_freeing_devm(int id)
70 {
71 if (option_project != PROJ_KERNEL)
72 return;
73
74 my_id = id;
75
76 add_function_assign_hook("devm_kmalloc", &match_assign, NULL);
77 add_function_assign_hook("devm_kzalloc", &match_assign, NULL);
78 add_function_assign_hook("devm_kcalloc", &match_assign, NULL);
79 add_function_assign_hook("devm_kmalloc_array", &match_assign, NULL);
80
81
82 add_function_hook("kfree", &match_free_func, INT_PTR(0));
83 add_function_hook("krealloc", &match_free_func, INT_PTR(0));
84 register_funcs_from_file();
85 }
86