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 "smatch.h"
19 
20 static int my_id;
21 
22 static struct {
23 	int name_param;
24 	int mode_param;
25 } param_index[] = {
26 	{.name_param = 0, .mode_param = 1},
27 	{.name_param = 1, .mode_param = 2},
28 };
29 
30 #define S_IWOTH 00002
31 
match_create(const char * fn,struct expression * expr,void * _param_type)32 static void match_create(const char *fn, struct expression *expr, void *_param_type)
33 {
34 	struct expression *arg_expr;
35 	sval_t sval;
36 	char *name;
37 	int idx = PTR_INT(_param_type);
38 
39 	arg_expr = get_argument_from_call_expr(expr->args, param_index[idx].mode_param);
40 	if (!get_implied_value(arg_expr, &sval))
41 		return;
42 	if (!(sval.uvalue & S_IWOTH))
43 		return;
44 	arg_expr = get_argument_from_call_expr(expr->args, param_index[idx].name_param);
45 	name = expr_to_var(arg_expr);
46 	sm_warning("proc file '%s' is world writable", name);
47 	free_string(name);
48 }
49 
check_proc_create(int id)50 void check_proc_create(int id)
51 {
52 	my_id = id;
53 	if (option_project != PROJ_KERNEL)
54 		return;
55 
56 	add_function_hook("proc_create", &match_create, INT_PTR(0));
57 	add_function_hook("create_proc_entry", &match_create, INT_PTR(0));
58 	add_function_hook("proc_create_data", &match_create, INT_PTR(0));
59 	add_function_hook("proc_net_fops_create", match_create, INT_PTR(1));
60 }
61