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
20static int my_id;
21
22extern int check_assigned_expr_id;
23
24static int is_kmalloc_call(struct expression *expr)
25{
26	if (expr->type != EXPR_CALL)
27		return 0;
28	if (expr->fn->type != EXPR_SYMBOL)
29		return 0;
30	if (!strcmp(expr->fn->symbol_name->name, "kmalloc"))
31		return 1;
32	if (!strcmp(expr->fn->symbol_name->name, "kzalloc"))
33		return 1;
34	return 0;
35}
36
37static void match_condition(struct expression *expr)
38{
39	char *macro;
40	struct smatch_state *state;
41	struct expression *right;
42	char *name;
43
44	macro = get_macro_name(expr->pos);
45	if (!macro || strcmp(macro, "BUG_ON") != 0)
46		return;
47	state = get_state_expr(check_assigned_expr_id, expr);
48	if (!state || !state->data)
49		return;
50	right = (struct expression *)state->data;
51	if (!is_kmalloc_call(right))
52		return;
53
54	name = expr_to_var(expr);
55	sm_warning("bug on allocation failure '%s'", name);
56	free_string(name);
57}
58
59void check_kmalloc_to_bugon(int id)
60{
61	if (option_project != PROJ_KERNEL)
62		return;
63	if (!option_spammy)
64		return;
65	my_id = id;
66	add_hook(&match_condition, CONDITION_HOOK);
67}
68