1*4882a593Smuzhiyun /*
2*4882a593Smuzhiyun * Copyright 2006, Red Hat, Inc., Dave Jones
3*4882a593Smuzhiyun * Released under the General Public License (GPL).
4*4882a593Smuzhiyun *
5*4882a593Smuzhiyun * This file contains the linked list validation for DEBUG_LIST.
6*4882a593Smuzhiyun */
7*4882a593Smuzhiyun
8*4882a593Smuzhiyun #include <linux/export.h>
9*4882a593Smuzhiyun #include <linux/list.h>
10*4882a593Smuzhiyun #include <linux/bug.h>
11*4882a593Smuzhiyun #include <linux/kernel.h>
12*4882a593Smuzhiyun #include <linux/rculist.h>
13*4882a593Smuzhiyun
14*4882a593Smuzhiyun /*
15*4882a593Smuzhiyun * Check that the data structures for the list manipulations are reasonably
16*4882a593Smuzhiyun * valid. Failures here indicate memory corruption (and possibly an exploit
17*4882a593Smuzhiyun * attempt).
18*4882a593Smuzhiyun */
19*4882a593Smuzhiyun
__list_add_valid(struct list_head * new,struct list_head * prev,struct list_head * next)20*4882a593Smuzhiyun bool __list_add_valid(struct list_head *new, struct list_head *prev,
21*4882a593Smuzhiyun struct list_head *next)
22*4882a593Smuzhiyun {
23*4882a593Smuzhiyun if (CHECK_DATA_CORRUPTION(prev == NULL,
24*4882a593Smuzhiyun "list_add corruption. prev is NULL.\n") ||
25*4882a593Smuzhiyun CHECK_DATA_CORRUPTION(next == NULL,
26*4882a593Smuzhiyun "list_add corruption. next is NULL.\n") ||
27*4882a593Smuzhiyun CHECK_DATA_CORRUPTION(next->prev != prev,
28*4882a593Smuzhiyun "list_add corruption. next->prev should be prev (%px), but was %px. (next=%px).\n",
29*4882a593Smuzhiyun prev, next->prev, next) ||
30*4882a593Smuzhiyun CHECK_DATA_CORRUPTION(prev->next != next,
31*4882a593Smuzhiyun "list_add corruption. prev->next should be next (%px), but was %px. (prev=%px).\n",
32*4882a593Smuzhiyun next, prev->next, prev) ||
33*4882a593Smuzhiyun CHECK_DATA_CORRUPTION(new == prev || new == next,
34*4882a593Smuzhiyun "list_add double add: new=%px, prev=%px, next=%px.\n",
35*4882a593Smuzhiyun new, prev, next))
36*4882a593Smuzhiyun return false;
37*4882a593Smuzhiyun
38*4882a593Smuzhiyun return true;
39*4882a593Smuzhiyun }
40*4882a593Smuzhiyun EXPORT_SYMBOL(__list_add_valid);
41*4882a593Smuzhiyun
__list_del_entry_valid(struct list_head * entry)42*4882a593Smuzhiyun bool __list_del_entry_valid(struct list_head *entry)
43*4882a593Smuzhiyun {
44*4882a593Smuzhiyun struct list_head *prev, *next;
45*4882a593Smuzhiyun
46*4882a593Smuzhiyun prev = entry->prev;
47*4882a593Smuzhiyun next = entry->next;
48*4882a593Smuzhiyun
49*4882a593Smuzhiyun if (CHECK_DATA_CORRUPTION(next == NULL,
50*4882a593Smuzhiyun "list_del corruption, %px->next is NULL\n", entry) ||
51*4882a593Smuzhiyun CHECK_DATA_CORRUPTION(prev == NULL,
52*4882a593Smuzhiyun "list_del corruption, %px->prev is NULL\n", entry) ||
53*4882a593Smuzhiyun CHECK_DATA_CORRUPTION(next == LIST_POISON1,
54*4882a593Smuzhiyun "list_del corruption, %px->next is LIST_POISON1 (%px)\n",
55*4882a593Smuzhiyun entry, LIST_POISON1) ||
56*4882a593Smuzhiyun CHECK_DATA_CORRUPTION(prev == LIST_POISON2,
57*4882a593Smuzhiyun "list_del corruption, %px->prev is LIST_POISON2 (%px)\n",
58*4882a593Smuzhiyun entry, LIST_POISON2) ||
59*4882a593Smuzhiyun CHECK_DATA_CORRUPTION(prev->next != entry,
60*4882a593Smuzhiyun "list_del corruption. prev->next should be %px, but was %px\n",
61*4882a593Smuzhiyun entry, prev->next) ||
62*4882a593Smuzhiyun CHECK_DATA_CORRUPTION(next->prev != entry,
63*4882a593Smuzhiyun "list_del corruption. next->prev should be %px, but was %px\n",
64*4882a593Smuzhiyun entry, next->prev))
65*4882a593Smuzhiyun return false;
66*4882a593Smuzhiyun
67*4882a593Smuzhiyun return true;
68*4882a593Smuzhiyun
69*4882a593Smuzhiyun }
70*4882a593Smuzhiyun EXPORT_SYMBOL(__list_del_entry_valid);
71