check_kernel.c

   1 /*
   2  * sparse/check_kernel.c
   3  *
   4  * Copyright (C) 2010 Dan Carpenter.
   5  *
   6  * Licensed under the Open Software License version 1.1
   7  *
   8  */
   9
  10 /*
  11  * This is kernel specific stuff for smatch_extra.
  12  */
  13
  14 #include "smatch.h"
  15 #include "smatch_extra.h"
  16
  17 static int implied_copy_return(struct expression *call, void *unused, struct range_list **rl)
  18 {
  19         struct expression *arg;
  20         sval_t max;
  21
  22         arg = get_argument_from_call_expr(call->args, 2);
  23         get_absolute_max(arg, &max);
  24         *rl = alloc_rl(ll_to_sval(0), max);
  25         return 1;
  26 }
  27
  28 static void match_param_nonnull(const char *fn, struct expression *call_expr,
  29                         struct expression *assign_expr, void *_param)
  30 {
  31         int param = PTR_INT(_param);
  32         struct expression *arg;
  33         struct smatch_state *pre_state;
  34         struct smatch_state *true_state;
  35
  36         arg = get_argument_from_call_expr(call_expr->args, param);
  37         pre_state = get_state_expr(SMATCH_EXTRA, arg);
  38         true_state = estate_filter_sval(pre_state, ll_to_sval(0));
  39         set_extra_expr_nomod(arg, true_state);
  40 }
  41
  42 static void match_container_of(const char *fn, struct expression *expr, void *unused)
  43 {
  44         set_extra_expr_mod(expr->left, alloc_estate_range(valid_ptr_min_sval, valid_ptr_max_sval));
  45 }
  46
  47 void check_kernel(int id)
  48 {
  49         if (option_project != PROJ_KERNEL)
  50                 return;
  51
  52         return_implies_state("tomoyo_memory_ok", 1, 1, &match_param_nonnull, (void *)0);
  53         add_macro_assign_hook_extra("container_of", &match_container_of, NULL);
  54
  55         add_implied_return_hook("copy_to_user", &implied_copy_return, NULL);
  56         add_implied_return_hook("__copy_to_user", &implied_copy_return, NULL);
  57         add_implied_return_hook("copy_from_user", &implied_copy_return, NULL);
  58         add_implied_return_hook("__copy_fom_user", &implied_copy_return, NULL);
  59         add_implied_return_hook("clear_user", &implied_copy_return, NULL);
  60 }