1/*
  2 * Copyright 2006, Red Hat, Inc., Dave Jones
  3 * Released under the General Public License (GPL).
  4 *
  5 * This file contains the linked list implementations for
  6 * DEBUG_LIST.
  7 */
  8
  9#include <linux/export.h>
 10#include <linux/list.h>
 11#include <linux/bug.h>
 12#include <linux/kernel.h>
 13#include <linux/rculist.h>
 14
 15/*
 16 * Insert a new entry between two known consecutive entries.
 17 *
 18 * This is only for internal list manipulation where we know
 19 * the prev/next entries already!
 20 */
 21
 22void __list_add(struct list_head *new,
 23			      struct list_head *prev,
 24			      struct list_head *next)
 25{
 26	WARN(next->prev != prev,
 27		"list_add corruption. next->prev should be "
 28		"prev (%p), but was %p. (next=%p).\n",
 29		prev, next->prev, next);
 30	WARN(prev->next != next,
 31		"list_add corruption. prev->next should be "
 32		"next (%p), but was %p. (prev=%p).\n",
 33		next, prev->next, prev);
 34	WARN(new == prev || new == next,
 35	     "list_add double add: new=%p, prev=%p, next=%p.\n",
 36	     new, prev, next);
 37	next->prev = new;
 38	new->next = next;
 39	new->prev = prev;
 40	prev->next = new;
 41}
 42EXPORT_SYMBOL(__list_add);
 43
 44void __list_del_entry(struct list_head *entry)
 45{
 46	struct list_head *prev, *next;
 47
 48	prev = entry->prev;
 49	next = entry->next;
 50
 51	if (WARN(next == LIST_POISON1,
 52		"list_del corruption, %p->next is LIST_POISON1 (%p)\n",
 53		entry, LIST_POISON1) ||
 54	    WARN(prev == LIST_POISON2,
 55		"list_del corruption, %p->prev is LIST_POISON2 (%p)\n",
 56		entry, LIST_POISON2) ||
 57	    WARN(prev->next != entry,
 58		"list_del corruption. prev->next should be %p, "
 59		"but was %p\n", entry, prev->next) ||
 60	    WARN(next->prev != entry,
 61		"list_del corruption. next->prev should be %p, "
 62		"but was %p\n", entry, next->prev))
 63		return;
 64
 65	__list_del(prev, next);
 66}
 67EXPORT_SYMBOL(__list_del_entry);
 68
 69/**
 70 * list_del - deletes entry from list.
 71 * @entry: the element to delete from the list.
 72 * Note: list_empty on entry does not return true after this, the entry is
 73 * in an undefined state.
 74 */
 75void list_del(struct list_head *entry)
 76{
 77	__list_del_entry(entry);
 78	entry->next = LIST_POISON1;
 79	entry->prev = LIST_POISON2;
 80}
 81EXPORT_SYMBOL(list_del);
 82
 83/*
 84 * RCU variants.
 85 */
 86void __list_add_rcu(struct list_head *new,
 87		    struct list_head *prev, struct list_head *next)
 88{
 89	WARN(next->prev != prev,
 90		"list_add_rcu corruption. next->prev should be prev (%p), but was %p. (next=%p).\n",
 91		prev, next->prev, next);
 92	WARN(prev->next != next,
 93		"list_add_rcu corruption. prev->next should be next (%p), but was %p. (prev=%p).\n",
 94		next, prev->next, prev);
 95	new->next = next;
 96	new->prev = prev;
 97	rcu_assign_pointer(list_next_rcu(prev), new);
 98	next->prev = new;
 99}
100EXPORT_SYMBOL(__list_add_rcu);

 1/*
 2 * Copyright 2006, Red Hat, Inc., Dave Jones
 3 * Released under the General Public License (GPL).
 4 *
 5 * This file contains the linked list validation for DEBUG_LIST.
 
 6 */
 7
 8#include <linux/export.h>
 9#include <linux/list.h>
10#include <linux/bug.h>
11#include <linux/kernel.h>
12#include <linux/rculist.h>
13
14/*
15 * Check that the data structures for the list manipulations are reasonably
16 * valid. Failures here indicate memory corruption (and possibly an exploit
17 * attempt).
 
18 */
19
20bool __list_add_valid(struct list_head *new, struct list_head *prev,
21		      struct list_head *next)
 
22{
23	CHECK_DATA_CORRUPTION(next->prev != prev,
24		"list_add corruption. next->prev should be prev (%p), but was %p. (next=%p).\n",
 
25		prev, next->prev, next);
26	CHECK_DATA_CORRUPTION(prev->next != next,
27		"list_add corruption. prev->next should be next (%p), but was %p. (prev=%p).\n",
 
28		next, prev->next, prev);
29	CHECK_DATA_CORRUPTION(new == prev || new == next,
30		"list_add double add: new=%p, prev=%p, next=%p.\n",
31		new, prev, next);
32
33	return true;
 
 
34}
35EXPORT_SYMBOL(__list_add_valid);
36
37bool __list_del_entry_valid(struct list_head *entry)
38{
39	struct list_head *prev, *next;
40
41	prev = entry->prev;
42	next = entry->next;
43
44	CHECK_DATA_CORRUPTION(next == LIST_POISON1,
45		"list_del corruption, %p->next is LIST_POISON1 (%p)\n",
46		entry, LIST_POISON1);
47	CHECK_DATA_CORRUPTION(prev == LIST_POISON2,
48		"list_del corruption, %p->prev is LIST_POISON2 (%p)\n",
49		entry, LIST_POISON2);
50	CHECK_DATA_CORRUPTION(prev->next != entry,
51		"list_del corruption. prev->next should be %p, but was %p\n",
52		entry, prev->next);
53	CHECK_DATA_CORRUPTION(next->prev != entry,
54		"list_del corruption. next->prev should be %p, but was %p\n",
55		entry, next->prev);
56	return true;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
57
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
58}
59EXPORT_SYMBOL(__list_del_entry_valid);