Dave Jones | 199a9af | 2006-09-29 01:59:00 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Copyright 2006, Red Hat, Inc., Dave Jones |
| 3 | * Released under the General Public License (GPL). |
| 4 | * |
Kees Cook | d7c8167 | 2016-08-17 14:42:08 -0700 | [diff] [blame] | 5 | * This file contains the linked list validation for DEBUG_LIST. |
Dave Jones | 199a9af | 2006-09-29 01:59:00 -0700 | [diff] [blame] | 6 | */ |
| 7 | |
Paul Gortmaker | 8bc3bcc | 2011-11-16 21:29:17 -0500 | [diff] [blame] | 8 | #include <linux/export.h> |
Dave Jones | 199a9af | 2006-09-29 01:59:00 -0700 | [diff] [blame] | 9 | #include <linux/list.h> |
Paul Gortmaker | 50af5ea | 2012-01-20 18:35:53 -0500 | [diff] [blame] | 10 | #include <linux/bug.h> |
Paul Gortmaker | b116ee4 | 2012-01-20 18:46:49 -0500 | [diff] [blame] | 11 | #include <linux/kernel.h> |
Dave Jones | 559f9ba | 2012-03-14 22:17:39 -0400 | [diff] [blame] | 12 | #include <linux/rculist.h> |
Dave Jones | 199a9af | 2006-09-29 01:59:00 -0700 | [diff] [blame] | 13 | |
| 14 | /* |
Kees Cook | d7c8167 | 2016-08-17 14:42:08 -0700 | [diff] [blame] | 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). |
Dave Jones | 199a9af | 2006-09-29 01:59:00 -0700 | [diff] [blame] | 18 | */ |
| 19 | |
Kees Cook | d7c8167 | 2016-08-17 14:42:08 -0700 | [diff] [blame] | 20 | bool __list_add_valid(struct list_head *new, struct list_head *prev, |
| 21 | struct list_head *next) |
Dave Jones | 199a9af | 2006-09-29 01:59:00 -0700 | [diff] [blame] | 22 | { |
Kees Cook | 85caa95 | 2017-02-24 15:00:38 -0800 | [diff] [blame] | 23 | if (CHECK_DATA_CORRUPTION(next->prev != prev, |
Matthew Wilcox | 68c1f08 | 2018-04-10 16:33:06 -0700 | [diff] [blame] | 24 | "list_add corruption. next->prev should be prev (%px), but was %px. (next=%px).\n", |
Kees Cook | 85caa95 | 2017-02-24 15:00:38 -0800 | [diff] [blame] | 25 | prev, next->prev, next) || |
| 26 | CHECK_DATA_CORRUPTION(prev->next != next, |
Matthew Wilcox | 68c1f08 | 2018-04-10 16:33:06 -0700 | [diff] [blame] | 27 | "list_add corruption. prev->next should be next (%px), but was %px. (prev=%px).\n", |
Kees Cook | 85caa95 | 2017-02-24 15:00:38 -0800 | [diff] [blame] | 28 | next, prev->next, prev) || |
| 29 | CHECK_DATA_CORRUPTION(new == prev || new == next, |
Matthew Wilcox | 68c1f08 | 2018-04-10 16:33:06 -0700 | [diff] [blame] | 30 | "list_add double add: new=%px, prev=%px, next=%px.\n", |
Kees Cook | 85caa95 | 2017-02-24 15:00:38 -0800 | [diff] [blame] | 31 | new, prev, next)) |
| 32 | return false; |
Kees Cook | de54ebbe | 2016-08-17 14:42:11 -0700 | [diff] [blame] | 33 | |
Kees Cook | d7c8167 | 2016-08-17 14:42:08 -0700 | [diff] [blame] | 34 | return true; |
Dave Jones | 199a9af | 2006-09-29 01:59:00 -0700 | [diff] [blame] | 35 | } |
Kees Cook | d7c8167 | 2016-08-17 14:42:08 -0700 | [diff] [blame] | 36 | EXPORT_SYMBOL(__list_add_valid); |
Dave Jones | 199a9af | 2006-09-29 01:59:00 -0700 | [diff] [blame] | 37 | |
Kees Cook | 0cd340d | 2016-08-17 14:42:10 -0700 | [diff] [blame] | 38 | bool __list_del_entry_valid(struct list_head *entry) |
Linus Torvalds | 3c18d4d | 2011-02-18 11:32:28 -0800 | [diff] [blame] | 39 | { |
| 40 | struct list_head *prev, *next; |
| 41 | |
| 42 | prev = entry->prev; |
| 43 | next = entry->next; |
| 44 | |
Kees Cook | 85caa95 | 2017-02-24 15:00:38 -0800 | [diff] [blame] | 45 | if (CHECK_DATA_CORRUPTION(next == LIST_POISON1, |
Matthew Wilcox | 68c1f08 | 2018-04-10 16:33:06 -0700 | [diff] [blame] | 46 | "list_del corruption, %px->next is LIST_POISON1 (%px)\n", |
Kees Cook | 85caa95 | 2017-02-24 15:00:38 -0800 | [diff] [blame] | 47 | entry, LIST_POISON1) || |
| 48 | CHECK_DATA_CORRUPTION(prev == LIST_POISON2, |
Matthew Wilcox | 68c1f08 | 2018-04-10 16:33:06 -0700 | [diff] [blame] | 49 | "list_del corruption, %px->prev is LIST_POISON2 (%px)\n", |
Kees Cook | 85caa95 | 2017-02-24 15:00:38 -0800 | [diff] [blame] | 50 | entry, LIST_POISON2) || |
| 51 | CHECK_DATA_CORRUPTION(prev->next != entry, |
Matthew Wilcox | 68c1f08 | 2018-04-10 16:33:06 -0700 | [diff] [blame] | 52 | "list_del corruption. prev->next should be %px, but was %px\n", |
Kees Cook | 85caa95 | 2017-02-24 15:00:38 -0800 | [diff] [blame] | 53 | entry, prev->next) || |
| 54 | CHECK_DATA_CORRUPTION(next->prev != entry, |
Matthew Wilcox | 68c1f08 | 2018-04-10 16:33:06 -0700 | [diff] [blame] | 55 | "list_del corruption. next->prev should be %px, but was %px\n", |
Kees Cook | 85caa95 | 2017-02-24 15:00:38 -0800 | [diff] [blame] | 56 | entry, next->prev)) |
| 57 | return false; |
| 58 | |
Kees Cook | 0cd340d | 2016-08-17 14:42:10 -0700 | [diff] [blame] | 59 | return true; |
Linus Torvalds | 3c18d4d | 2011-02-18 11:32:28 -0800 | [diff] [blame] | 60 | |
Linus Torvalds | 3c18d4d | 2011-02-18 11:32:28 -0800 | [diff] [blame] | 61 | } |
Kees Cook | 0cd340d | 2016-08-17 14:42:10 -0700 | [diff] [blame] | 62 | EXPORT_SYMBOL(__list_del_entry_valid); |