poison.h

 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#ifdef __cplusplus
19#define LIST_POISON1  NULL
20#define LIST_POISON2  NULL
21#else
22/*
23 * These are non-NULL pointers that will result in page faults
24 * under normal circumstances, used to verify that nobody uses
25 * non-initialized list entries.
26 */
27#define LIST_POISON1  ((void *) 0x100 + POISON_POINTER_DELTA)
28#define LIST_POISON2  ((void *) 0x200 + POISON_POINTER_DELTA)
29#endif
30
31/********** include/linux/timer.h **********/
32/*
33 * Magic number "tsta" to indicate a static timer initializer
34 * for the object debugging code.
35 */
36#define TIMER_ENTRY_STATIC	((void *) 0x300 + POISON_POINTER_DELTA)
37
38/********** mm/page_poison.c **********/
39#define PAGE_POISON 0xaa
40
41/********** mm/page_alloc.c ************/
42
43#define TAIL_MAPPING	((void *) 0x400 + POISON_POINTER_DELTA)
44
45/********** mm/slab.c **********/
46/*
47 * Magic nums for obj red zoning.
48 * Placed in the first word before and the first word after an obj.
49 */
50#define SLUB_RED_INACTIVE	0xbb	/* when obj is inactive */
51#define SLUB_RED_ACTIVE		0xcc	/* when obj is active */
52
53/* ...and for poisoning */
54#define	POISON_INUSE	0x5a	/* for use-uninitialised poisoning */
55#define POISON_FREE	0x6b	/* for use-after-free poisoning */
56#define	POISON_END	0xa5	/* end-byte of poisoning */
57
58/********** arch/$ARCH/mm/init.c **********/
59#define POISON_FREE_INITMEM	0xcc
60
61/********** arch/ia64/hp/common/sba_iommu.c **********/
62/*
63 * arch/ia64/hp/common/sba_iommu.c uses a 16-byte poison string with a
64 * value of "SBAIOMMU POISON\0" for spill-over poisoning.
65 */
66
67/********** fs/jbd/journal.c **********/
68#define JBD_POISON_FREE		0x5b
69#define JBD2_POISON_FREE	0x5c
70
71/********** drivers/base/dmapool.c **********/
72#define	POOL_POISON_FREED	0xa7	/* !inuse */
73#define	POOL_POISON_ALLOCATED	0xa9	/* !initted */
74
75/********** drivers/atm/ **********/
76#define ATM_POISON_FREE		0x12
77#define ATM_POISON		0xdeadbeef
78
79/********** kernel/mutexes **********/
80#define MUTEX_DEBUG_INIT	0x11
81#define MUTEX_DEBUG_FREE	0x22
82
83/********** security/ **********/
84#define KEY_DESTROY		0xbd
85
86#endif