db: rename FILTER_VALUE, LIMITED_VALUE, and ADDED_VALUE
[smatch.git] / check_frees_param.c
blob6d295488c7a44ae42711499956d1294187ece67c
1 /*
2 * Copyright (C) 2014 Oracle.
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.
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.
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
19 * This file is sort of like check_dereferences_param.c. In theory the one
20 * difference should be that the param is NULL it should still be counted as a
21 * free. But for now I don't handle that case.
24 #include "smatch.h"
25 #include "smatch_extra.h"
26 #include "smatch_slist.h"
28 static int my_id;
30 STATE(freed);
31 STATE(ignore);
32 STATE(param);
34 static void set_ignore(struct sm_state *sm, struct expression *mod_expr)
36 set_state(my_id, sm->name, sm->sym, &ignore);
39 static void match_function_def(struct symbol *sym)
41 struct symbol *arg;
42 int i;
44 i = -1;
45 FOR_EACH_PTR(sym->ctype.base_type->arguments, arg) {
46 i++;
47 if (!arg->ident)
48 continue;
49 set_state(my_id, arg->ident->name, arg, &param);
50 } END_FOR_EACH_PTR(arg);
53 static void freed_variable(struct expression *expr)
55 struct sm_state *sm;
57 expr = strip_expr(expr);
58 if (get_param_num(expr) < 0)
59 return;
61 sm = get_sm_state_expr(my_id, expr);
62 if (sm && slist_has_state(sm->possible, &ignore))
63 return;
64 set_state_expr(my_id, expr, &freed);
67 static void match_free(const char *fn, struct expression *expr, void *param)
69 struct expression *arg;
71 arg = get_argument_from_call_expr(expr->args, PTR_INT(param));
72 if (!arg)
73 return;
74 freed_variable(arg);
77 static void set_param_freed(struct expression *arg, char *key, char *unused)
79 /* XXX FIXME: call_implies has been updated with more information */
80 if (strcmp(key, "$") != 0)
81 return;
82 freed_variable(arg);
85 static void process_states(struct stree *stree)
87 struct sm_state *sm;
88 int param;
89 const char *param_name;
91 FOR_EACH_MY_SM(my_id, stree, sm) {
92 if (sm->state != &freed)
93 continue;
94 param = get_param_num_from_sym(sm->sym);
95 if (param < 0)
96 continue;
97 param_name = get_param_name(sm);
98 if (!param_name)
99 continue;
100 sql_insert_call_implies(PARAM_FREED, param, param_name, "1");
101 } END_FOR_EACH_SM(sm);
105 void check_frees_param(int id)
107 my_id = id;
109 add_hook(&match_function_def, FUNC_DEF_HOOK);
111 if (option_project == PROJ_KERNEL) {
112 add_function_hook("kfree", &match_free, INT_PTR(0));
113 add_function_hook("kmem_cache_free", &match_free, INT_PTR(1));
114 } else {
115 add_function_hook("free", &match_free, INT_PTR(0));
118 select_call_implies_hook(PARAM_FREED, &set_param_freed);
119 add_modification_hook(my_id, &set_ignore);
121 all_return_states_hook(&process_states);