check_proc_create.c

   1 /*
   2  * sparse/check_proc_create.c
   3  *
   4  * Copyright (C) 2010 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 struct {
  15         int name_param;
  16         int mode_param;
  17 } param_index[] = {
  18         {.name_param = 0, .mode_param = 1},
  19         {.name_param = 1, .mode_param = 2},
  20 };
  21
  22 #define S_IWOTH 00002
  23
  24 static void match_create(const char *fn, struct expression *expr, void *_param_type)
  25 {
  26         struct expression *arg_expr;
  27         sval_t sval;
  28         char *name;
  29         int idx = PTR_INT(_param_type);
  30
  31         arg_expr = get_argument_from_call_expr(expr->args, param_index[idx].mode_param);
  32         if (!get_implied_value(arg_expr, &sval))
  33                 return;
  34         if (!(sval.uvalue & S_IWOTH))
  35                 return;
  36         arg_expr = get_argument_from_call_expr(expr->args, param_index[idx].name_param);
  37         name = expr_to_var(arg_expr);
  38         sm_msg("warn: proc file '%s' is world writable", name);
  39         free_string(name);
  40 }
  41
  42 void check_proc_create(int id)
  43 {
  44         my_id = id;
  45         if (option_project != PROJ_KERNEL)
  46                 return;
  47
  48         add_function_hook("proc_create", &match_create, INT_PTR(0));
  49         add_function_hook("create_proc_entry", &match_create, INT_PTR(0));
  50         add_function_hook("proc_create_data", &match_create, INT_PTR(0));
  51         add_function_hook("proc_net_fops_create", match_create, INT_PTR(1));
  52 }