/* * 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){	if (CHECK_DATA_CORRUPTION(prev == NULL,			"list_add corruption. prev is NULL.\n") ||	    CHECK_DATA_CORRUPTION(next == NULL,			"list_add corruption. next is NULL.\n") ||	    CHECK_DATA_CORRUPTION(next->prev != prev,			"list_add corruption. next->prev should be prev (%px), but was %px. (next=%px).\n",			prev, next->prev, next) ||	    CHECK_DATA_CORRUPTION(prev->next != next,			"list_add corruption. prev->next should be next (%px), but was %px. (prev=%px).\n",			next, prev->next, prev) ||	    CHECK_DATA_CORRUPTION(new == prev || new == next,			"list_add double add: new=%px, prev=%px, next=%px.\n",			new, prev, next))		return false; 	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; 	if (CHECK_DATA_CORRUPTION(next == NULL,			"list_del corruption, %px->next is NULL\n", entry) ||	    CHECK_DATA_CORRUPTION(prev == NULL,			"list_del corruption, %px->prev is NULL\n", entry) ||	    CHECK_DATA_CORRUPTION(next == LIST_POISON1,			"list_del corruption, %px->next is LIST_POISON1 (%px)\n",			entry, LIST_POISON1) ||	    CHECK_DATA_CORRUPTION(prev == LIST_POISON2,			"list_del corruption, %px->prev is LIST_POISON2 (%px)\n",			entry, LIST_POISON2) ||	    CHECK_DATA_CORRUPTION(prev->next != entry,			"list_del corruption. prev->next should be %px, but was %px. (prev=%px)\n",			entry, prev->next, prev) ||	    CHECK_DATA_CORRUPTION(next->prev != entry,			"list_del corruption. next->prev should be %px, but was %px. (next=%px)\n",			entry, next->prev, next))		return false; 	return true; }EXPORT_SYMBOL(__list_del_entry_valid);