| /* |
| * 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> |
| #include <linux/bug.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(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 false; |
| |
| next->prev = new; |
| new->next = next; |
| new->prev = prev; |
| WRITE_ONCE(prev->next, new); |
| |
| 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 == 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 false; |
| |
| return true; |
| |
| } |
| EXPORT_SYMBOL(__list_del_entry_valid); |