check_type.c

   1 /*
   2  * sparse/check_type.c
   3  *
   4  * Copyright (C) 2009 Dan Carpenter.
   5  *
   6  * Licensed under the Open Software License version 1.1
   7  *
   8  */
   9
  10 #include "smatch.h"
  11
  12 static int my_id;
  13
  14 static void match_free(const char *fn, struct expression *expr, void *data)
  15 {
  16         struct expression *arg_expr;
  17         char *name;
  18         struct symbol *type;
  19
  20         arg_expr = get_argument_from_call_expr(expr->args, 0);
  21         type = get_type(arg_expr);
  22
  23         if (!type || (type->type != SYM_PTR && type->type != SYM_ARRAY))
  24                 return;
  25         type = get_base_type(type);
  26
  27         if (!type || !type->ident)
  28                 return;
  29
  30         name = get_variable_from_expr_complex(arg_expr, NULL);
  31
  32         if (!strcmp("sk_buff", type->ident->name))
  33                 sm_msg("error: use kfree_skb() here instead of kfree(%s)", name);
  34         else if (!strcmp("net_device", type->ident->name))
  35                 sm_msg("error: use free_netdev() here instead of kfree(%s)", name);
  36
  37         free_string(name);
  38 }
  39
  40 void check_type(int id)
  41 {
  42         my_id = id;
  43         if (option_project == PROJ_KERNEL)
  44                 add_function_hook("kfree", &match_free, NULL);
  45 }