/* * Copyright 2006, Red Hat, Inc., Dave Jones * Released under the General Public License (GPL). * * This file contains the linked list validation and error reporting for * LIST_HARDENED and 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). */ __list_valid_slowpath bool __list_add_valid_or_report(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_or_report); __list_valid_slowpath bool __list_del_entry_valid_or_report(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_or_report);