[mirror_ubuntu-artful-kernel.git] / lib / list_debug.c

/*
 * Copyright 2006, Red Hat, Inc., Dave Jones
 * Released under the General Public License (GPL).
 *
 * This file contains the linked list validation for DEBUG_LIST.
 */

#include <linux/export.h>
#include <linux/list.h>
#include <linux/bug.h>
#include <linux/kernel.h>
#include <linux/rculist.h>

/*
 * Check that the data structures for the list manipulations are reasonably
 * valid. Failures here indicate memory corruption (and possibly an exploit
 * attempt).
 */

bool __list_add_valid(struct list_head *new, struct list_head *prev,
		      struct list_head *next)
{
	CHECK_DATA_CORRUPTION(next->prev != prev,
		"list_add corruption. next->prev should be prev (%p), but was %p. (next=%p).\n",
		prev, next->prev, next);
	CHECK_DATA_CORRUPTION(prev->next != next,
		"list_add corruption. prev->next should be next (%p), but was %p. (prev=%p).\n",
		next, prev->next, prev);
	CHECK_DATA_CORRUPTION(new == prev || new == next,
		"list_add double add: new=%p, prev=%p, next=%p.\n",
		new, prev, next);

	return true;
}
EXPORT_SYMBOL(__list_add_valid);

bool __list_del_entry_valid(struct list_head *entry)
{
	struct list_head *prev, *next;

	prev = entry->prev;
	next = entry->next;

	CHECK_DATA_CORRUPTION(next == LIST_POISON1,
		"list_del corruption, %p->next is LIST_POISON1 (%p)\n",
		entry, LIST_POISON1);
	CHECK_DATA_CORRUPTION(prev == LIST_POISON2,
		"list_del corruption, %p->prev is LIST_POISON2 (%p)\n",
		entry, LIST_POISON2);
	CHECK_DATA_CORRUPTION(prev->next != entry,
		"list_del corruption. prev->next should be %p, but was %p\n",
		entry, prev->next);
	CHECK_DATA_CORRUPTION(next->prev != entry,
		"list_del corruption. next->prev should be %p, but was %p\n",
		entry, next->prev);
	return true;

}
EXPORT_SYMBOL(__list_del_entry_valid);
Commit	Line	Data
	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
	20	bool __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	}
	35	EXPORT_SYMBOL(__list_add_valid);
	36
	37	bool __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	}
	59	EXPORT_SYMBOL(__list_del_entry_valid);