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 /* 19 * Complains about places that return -1 instead of -ENOMEM 20 */ 21 22 #include "smatch.h" 23 #include "smatch_slist.h" 24 #include "smatch_extra.h" 25 26 static int my_id; 27 28 static void match_return(struct expression *ret_value) 29 { 30 struct expression *expr; 31 struct sm_state *sm; 32 struct stree *stree; 33 sval_t sval; 34 35 if (!ret_value) 36 return; 37 if (returns_unsigned(cur_func_sym)) 38 return; 39 if (returns_pointer(cur_func_sym)) 40 return; 41 if (!get_value(ret_value, &sval) || sval.value != -1) 42 return; 43 if (get_macro_name(ret_value->pos)) 44 return; 45 46 stree = __get_cur_stree(); 47 48 FOR_EACH_MY_SM(SMATCH_EXTRA, stree, sm) { 49 if (!estate_get_single_value(sm->state, &sval) || sval.value != 0) 50 continue; 51 expr = get_assigned_expr_name_sym(sm->name, sm->sym); 52 if (!expr) 53 continue; 54 if (expr->type != EXPR_CALL || expr->fn->type != EXPR_SYMBOL) 55 continue; 56 if (!expr->fn->symbol_name) 57 continue; 58 /* To be honest the correct check is: 59 * if (strstr(expr->fn->symbol_name->name, "alloc")) 60 * complain(); 61 * But it generates too many warnings and it's too depressing. 62 */ 63 if (strcmp(expr->fn->symbol_name->name, "kmalloc") != 0 && 64 strcmp(expr->fn->symbol_name->name, "kzalloc") != 0) 65 continue; 66 67 sm_warning("returning -1 instead of -ENOMEM is sloppy"); 68 return; 69 70 } END_FOR_EACH_SM(sm); 71 } 72 73 void check_return_enomem(int id) 74 { 75 if (option_project != PROJ_KERNEL) 76 return; 77 78 my_id = id; 79 add_hook(&match_return, RETURN_HOOK); 80 }