1*1f5207b7SJohn Levon /*
2*1f5207b7SJohn Levon  * Copyright (C) 2010 Dan Carpenter.
3*1f5207b7SJohn Levon  *
4*1f5207b7SJohn Levon  * This program is free software; you can redistribute it and/or
5*1f5207b7SJohn Levon  * modify it under the terms of the GNU General Public License
6*1f5207b7SJohn Levon  * as published by the Free Software Foundation; either version 2
7*1f5207b7SJohn Levon  * of the License, or (at your option) any later version.
8*1f5207b7SJohn Levon  *
9*1f5207b7SJohn Levon  * This program is distributed in the hope that it will be useful,
10*1f5207b7SJohn Levon  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12*1f5207b7SJohn Levon  * GNU General Public License for more details.
13*1f5207b7SJohn Levon  *
14*1f5207b7SJohn Levon  * You should have received a copy of the GNU General Public License
15*1f5207b7SJohn Levon  * along with this program; if not, see http://www.gnu.org/copyleft/gpl.txt
16*1f5207b7SJohn Levon  */
17*1f5207b7SJohn Levon 
18*1f5207b7SJohn Levon #include "smatch.h"
19*1f5207b7SJohn Levon 
match_strcpy(const char * fn,struct expression * expr,void * unused)20*1f5207b7SJohn Levon static void match_strcpy(const char *fn, struct expression *expr, void *unused)
21*1f5207b7SJohn Levon {
22*1f5207b7SJohn Levon 	struct expression *dest;
23*1f5207b7SJohn Levon 	struct expression *data;
24*1f5207b7SJohn Levon 	char *dest_name = NULL;
25*1f5207b7SJohn Levon 	char *data_name = NULL;
26*1f5207b7SJohn Levon 	int dest_size;
27*1f5207b7SJohn Levon 	int data_size;
28*1f5207b7SJohn Levon 
29*1f5207b7SJohn Levon 	dest = get_argument_from_call_expr(expr->args, 0);
30*1f5207b7SJohn Levon 	data = get_argument_from_call_expr(expr->args, 1);
31*1f5207b7SJohn Levon 	dest_size = get_array_size_bytes(dest);
32*1f5207b7SJohn Levon 	if (!dest_size)
33*1f5207b7SJohn Levon 		return;
34*1f5207b7SJohn Levon 
35*1f5207b7SJohn Levon 	data_size = get_size_from_strlen(data);
36*1f5207b7SJohn Levon 	if (!data_size)
37*1f5207b7SJohn Levon 		data_size = get_array_size_bytes(data);
38*1f5207b7SJohn Levon 
39*1f5207b7SJohn Levon 	/* If the size of both arrays is known and the destination
40*1f5207b7SJohn Levon 	 * buffer is larger than the source buffer, we're okay.
41*1f5207b7SJohn Levon 	 */
42*1f5207b7SJohn Levon 	if (data_size && dest_size >= data_size)
43*1f5207b7SJohn Levon 		return;
44*1f5207b7SJohn Levon 
45*1f5207b7SJohn Levon 	dest_name = expr_to_str(dest);
46*1f5207b7SJohn Levon 	data_name = expr_to_str(data);
47*1f5207b7SJohn Levon 
48*1f5207b7SJohn Levon 	if (data_size)
49*1f5207b7SJohn Levon 		sm_error("%s() '%s' too large for '%s' (%d vs %d)",
50*1f5207b7SJohn Levon 			fn, data_name, dest_name, data_size, dest_size);
51*1f5207b7SJohn Levon 	else if (option_spammy)
52*1f5207b7SJohn Levon 		sm_warning("%s() '%s' of unknown size might be too large for '%s'",
53*1f5207b7SJohn Levon 			fn, data_name, dest_name);
54*1f5207b7SJohn Levon 
55*1f5207b7SJohn Levon 	free_string(dest_name);
56*1f5207b7SJohn Levon 	free_string(data_name);
57*1f5207b7SJohn Levon }
58*1f5207b7SJohn Levon 
check_strcpy_overflow(int id)59*1f5207b7SJohn Levon void check_strcpy_overflow(int id)
60*1f5207b7SJohn Levon {
61*1f5207b7SJohn Levon 	add_function_hook("strcpy", &match_strcpy, NULL);
62*1f5207b7SJohn Levon }