1 /* 2 * Copyright (C) 2009 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 /* 19 * This script is for finding functions like hcd_buffer_free() which free 20 * their arguments. After running it, add those functions to check_memory.c 21 */ 22 23 #include "smatch.h" 24 #include "smatch_slist.h" 25 26 static int my_id; 27 28 STATE(putted); 29 30 static struct symbol *this_func; 31 static struct tracker_list *putted_args = NULL; 32 33 static void match_function_def(struct symbol *sym) 34 { 35 this_func = sym; 36 } 37 38 static int parent_is_arg(struct symbol *sym) 39 { 40 struct symbol *arg; 41 42 FOR_EACH_PTR(this_func->ctype.base_type->arguments, arg) { 43 if (sym == arg) 44 return 1; 45 } END_FOR_EACH_PTR(arg); 46 return 0; 47 } 48 49 static void match_put(const char *fn, struct expression *expr, void *info) 50 { 51 struct expression *tmp; 52 struct symbol *sym; 53 char *name; 54 55 tmp = get_argument_from_call_expr(expr->args, 0); 56 tmp = strip_expr(tmp); 57 name = expr_to_var_sym(tmp, &sym); 58 free_string(name); 59 if (parent_is_arg(sym) && sym->ident) 60 set_state(my_id, sym->ident->name, sym, &putted); 61 } 62 63 static int return_count = 0; 64 static void match_return(struct expression *ret_value) 65 { 66 struct stree *stree; 67 struct sm_state *tmp; 68 struct tracker *tracker; 69 70 if (__inline_fn) 71 return; 72 73 if (!return_count) { 74 stree = __get_cur_stree(); 75 FOR_EACH_MY_SM(my_id, stree, tmp) { 76 if (tmp->state == &putted) 77 add_tracker(&putted_args, my_id, tmp->name, 78 tmp->sym); 79 } END_FOR_EACH_SM(tmp); 80 } else { 81 FOR_EACH_PTR(putted_args, tracker) { 82 tmp = get_sm_state(my_id, tracker->name, tracker->sym); 83 if (tmp && tmp->state != &putted) 84 del_tracker(&putted_args, my_id, tracker->name, 85 tracker->sym); 86 } END_FOR_EACH_PTR(tracker); 87 88 } 89 } 90 91 static void print_arg(struct symbol *sym) 92 { 93 struct symbol *arg; 94 int i = 0; 95 96 FOR_EACH_PTR(this_func->ctype.base_type->arguments, arg) { 97 if (sym == arg) { 98 sm_info("puts_arg %s %d", get_function(), i); 99 return; 100 } 101 i++; 102 } END_FOR_EACH_PTR(arg); 103 } 104 105 static void match_end_func(struct symbol *sym) 106 { 107 struct tracker *tracker; 108 109 if (__inline_fn) 110 return; 111 if (is_reachable()) 112 match_return(NULL); 113 114 FOR_EACH_PTR(putted_args, tracker) { 115 print_arg(tracker->sym); 116 } END_FOR_EACH_PTR(tracker); 117 118 free_trackers_and_list(&putted_args); 119 return_count = 0; 120 } 121 122 void check_puts_argument(int id) 123 { 124 if (!option_info || option_project != PROJ_KERNEL) 125 return; 126 127 my_id = id; 128 add_hook(&match_function_def, FUNC_DEF_HOOK); 129 add_function_hook("kobject_put", &match_put, NULL); 130 add_function_hook("kref_put", &match_put, NULL); 131 add_hook(&match_return, RETURN_HOOK); 132 add_hook(&match_end_func, END_FUNC_HOOK); 133 } 134