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 * Sometimes we aren't able to track a variable through a function call. This
20 * usually happens because a function changes too many variables so we give up.
21 * Another reason this happens is because we call a function pointer and there
22 * are too many functions which implement that function pointer so we give up.
23 * Also maybe we don't have the database enabled.
25 * The goal here is to make a call back so what if we call:
29 * but we're not able to say what happens to "foo", then let's assume that we
30 * don't know anything about "foo" if it's an untracked call.
35 #include "smatch_slist.h"
36 #include "smatch_extra.h"
44 typedef void (untracked_hook
)(struct expression
*call
, int param
);
45 DECLARE_PTR_LIST(untracked_hook_list
, untracked_hook
*);
46 static struct untracked_hook_list
*untracked_hooks
;
47 static struct untracked_hook_list
*lost_hooks
;
49 struct int_stack
*tracked_stack
;
51 void add_untracked_param_hook(void (func
)(struct expression
*call
, int param
))
53 untracked_hook
**p
= malloc(sizeof(untracked_hook
*));
55 add_ptr_list(&untracked_hooks
, p
);
58 static void call_untracked_callbacks(struct expression
*expr
, int param
)
62 FOR_EACH_PTR(untracked_hooks
, fn
) {
64 } END_FOR_EACH_PTR(fn
);
67 void add_lost_param_hook(void (func
)(struct expression
*call
, int param
))
69 untracked_hook
**p
= malloc(sizeof(untracked_hook
*));
71 add_ptr_list(&lost_hooks
, p
);
74 static void call_lost_callbacks(struct expression
*expr
, int param
)
78 FOR_EACH_PTR(lost_hooks
, fn
) {
80 } END_FOR_EACH_PTR(fn
);
83 static void assume_tracked(struct expression
*call_expr
, int param
, char *key
, char *value
)
88 static void mark_untracked_lost(struct expression
*expr
, int param
, const char *key
, int type
)
93 while (expr
->type
== EXPR_ASSIGNMENT
)
94 expr
= strip_expr(expr
->right
);
95 if (expr
->type
!= EXPR_CALL
)
98 name
= return_state_to_var_sym(expr
, param
, key
, &sym
);
102 if (type
== LOST_PARAM
)
103 call_lost_callbacks(expr
, param
);
104 call_untracked_callbacks(expr
, param
);
105 set_state(my_id
, name
, sym
, &untracked
);
111 void mark_untracked(struct expression
*expr
, int param
, const char *key
, const char *value
)
113 mark_untracked_lost(expr
, param
, key
, UNTRACKED_PARAM
);
116 void mark_lost(struct expression
*expr
, int param
, const char *key
, const char *value
)
118 mark_untracked_lost(expr
, param
, key
, LOST_PARAM
);
121 static int lost_in_va_args(struct expression
*expr
)
127 fn
= get_type(expr
->fn
);
128 if (!fn
|| !fn
->variadic
)
132 name
= expr_to_var(expr
->fn
);
133 if (name
&& strstr(name
, "print"))
140 static void match_after_call(struct expression
*expr
)
142 struct expression
*arg
;
146 if (lost_in_va_args(expr
))
155 FOR_EACH_PTR(expr
->args
, arg
) {
158 type
= get_type(arg
);
159 if (!type
|| type
->type
!= SYM_PTR
)
162 call_untracked_callbacks(expr
, i
);
163 set_state_expr(my_id
, arg
, &untracked
);
164 } END_FOR_EACH_PTR(arg
);
168 static void mark_all_params(int return_id
, char *return_ranges
, int type
)
174 FOR_EACH_PTR(cur_func_sym
->ctype
.base_type
->arguments
, arg
) {
179 sql_insert_return_states(return_id
, return_ranges
,
180 type
, param
, "$", "");
181 } END_FOR_EACH_PTR(arg
);
185 void mark_all_params_untracked(int return_id
, char *return_ranges
, struct expression
*expr
)
187 mark_all_params(return_id
, return_ranges
, UNTRACKED_PARAM
);
190 void mark_all_params_lost(int return_id
, char *return_ranges
, struct expression
*expr
)
192 mark_all_params(return_id
, return_ranges
, LOST_PARAM
);
195 static void print_untracked_params(int return_id
, char *return_ranges
, struct expression
*expr
)
203 FOR_EACH_PTR(cur_func_sym
->ctype
.base_type
->arguments
, arg
) {
209 if (__bail_on_rest_of_function
) {
210 /* hairy functions are lost */
212 } else if ((sm
= get_sm_state(my_id
, arg
->ident
->name
, arg
))) {
213 if (slist_has_state(sm
->possible
, &lost
))
216 type
= UNTRACKED_PARAM
;
221 sql_insert_return_states(return_id
, return_ranges
,
222 type
, param
, "$", "");
223 } END_FOR_EACH_PTR(arg
);
226 static void match_param_assign(struct expression
*expr
)
228 struct expression
*right
;
232 if (__in_fake_assign
)
235 right
= strip_expr(expr
->right
);
236 type
= get_type(right
);
237 if (!type
|| type
->type
!= SYM_PTR
)
240 param
= get_param_num(right
);
244 set_state_expr(my_id
, right
, &untracked
);
248 static void match_param_assign_in_asm(struct statement
*stmt
)
251 struct expression
*expr
;
256 FOR_EACH_PTR(stmt
->asm_inputs
, expr
) {
258 case 0: /* identifier */
259 case 1: /* constraint */
262 case 2: /* expression */
265 expr
= strip_expr(expr
);
266 type
= get_type(expr
);
267 if (!type
|| type
->type
!= SYM_PTR
)
269 param
= get_param_num(expr
);
272 set_state_expr(my_id
, expr
, &untracked
);
275 } END_FOR_EACH_PTR(expr
);
278 static void match_inline_start(struct expression
*expr
)
280 push_int(&tracked_stack
, tracked
);
283 static void match_inline_end(struct expression
*expr
)
285 tracked
= pop_int(&tracked_stack
);
288 void register_untracked_param(int id
)
292 select_return_states_hook(INTERNAL
, &assume_tracked
);
293 select_return_states_hook(UNTRACKED_PARAM
, &mark_untracked
);
294 select_return_states_hook(LOST_PARAM
, &mark_lost
);
295 add_hook(&match_after_call
, FUNCTION_CALL_HOOK_AFTER_DB
);
297 add_split_return_callback(&print_untracked_params
);
299 add_hook(&match_param_assign
, ASSIGNMENT_HOOK
);
300 add_hook(&match_param_assign_in_asm
, ASM_HOOK
);
302 add_hook(&match_inline_start
, INLINE_FN_START
);
303 add_hook(&match_inline_end
, INLINE_FN_END
);