1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _LINUX_POISON_H
3#define _LINUX_POISON_H
4
5/********** include/linux/list.h **********/
6
7/*
8 * Architectures might want to move the poison pointer offset
9 * into some well-recognized area such as 0xdead000000000000,
10 * that is also not mappable by user-space exploits:
11 */
12#ifdef CONFIG_ILLEGAL_POINTER_VALUE
13# define POISON_POINTER_DELTA _AC(CONFIG_ILLEGAL_POINTER_VALUE, UL)
14#else
15# define POISON_POINTER_DELTA 0
16#endif
17
18/*
19 * These are non-NULL pointers that will result in page faults
20 * under normal circumstances, used to verify that nobody uses
21 * non-initialized list entries.
22 */
23#define LIST_POISON1 ((void *) 0x100 + POISON_POINTER_DELTA)
24#define LIST_POISON2 ((void *) 0x122 + POISON_POINTER_DELTA)
25
26/********** include/linux/timer.h **********/
27#define TIMER_ENTRY_STATIC ((void *) 0x300 + POISON_POINTER_DELTA)
28
29/********** mm/page_poison.c **********/
30#define PAGE_POISON 0xaa
31
32/********** mm/page_alloc.c ************/
33
34#define TAIL_MAPPING ((void *) 0x400 + POISON_POINTER_DELTA)
35
36/********** mm/slab.c **********/
37/*
38 * Magic nums for obj red zoning.
39 * Placed in the first word before and the first word after an obj.
40 */
41#define RED_INACTIVE 0x09F911029D74E35BULL /* when obj is inactive */
42#define RED_ACTIVE 0xD84156C5635688C0ULL /* when obj is active */
43
44#define SLUB_RED_INACTIVE 0xbb
45#define SLUB_RED_ACTIVE 0xcc
46
47/* ...and for poisoning */
48#define POISON_INUSE 0x5a /* for use-uninitialised poisoning */
49#define POISON_FREE 0x6b /* for use-after-free poisoning */
50#define POISON_END 0xa5 /* end-byte of poisoning */
51
52/********** arch/$ARCH/mm/init.c **********/
53#define POISON_FREE_INITMEM 0xcc
54
55/********** arch/ia64/hp/common/sba_iommu.c **********/
56/*
57 * arch/ia64/hp/common/sba_iommu.c uses a 16-byte poison string with a
58 * value of "SBAIOMMU POISON\0" for spill-over poisoning.
59 */
60
61/********** fs/jbd/journal.c **********/
62#define JBD_POISON_FREE 0x5b
63#define JBD2_POISON_FREE 0x5c
64
65/********** drivers/base/dmapool.c **********/
66#define POOL_POISON_FREED 0xa7 /* !inuse */
67#define POOL_POISON_ALLOCATED 0xa9 /* !initted */
68
69/********** drivers/atm/ **********/
70#define ATM_POISON_FREE 0x12
71#define ATM_POISON 0xdeadbeef
72
73/********** kernel/mutexes **********/
74#define MUTEX_DEBUG_INIT 0x11
75#define MUTEX_DEBUG_FREE 0x22
76#define MUTEX_POISON_WW_CTX ((void *) 0x500 + POISON_POINTER_DELTA)
77
78/********** security/ **********/
79#define KEY_DESTROY 0xbd
80
81/********** net/core/page_pool.c **********/
82#define PP_SIGNATURE (0x40 + POISON_POINTER_DELTA)
83
84/********** net/core/skbuff.c **********/
85#define SKB_LIST_POISON_NEXT ((void *)(0x800 + POISON_POINTER_DELTA))
86
87/********** kernel/bpf/ **********/
88#define BPF_PTR_POISON ((void *)(0xeB9FUL + POISON_POINTER_DELTA))
89
90/********** VFS **********/
91#define VFS_PTR_POISON ((void *)(0xF5 + POISON_POINTER_DELTA))
92
93#endif
94

source code of linux/include/linux/poison.h