xref: /linux/tools/include/linux/poison.h (revision a1ff5a7d78a036d6c2178ee5acd6ba4946243800)
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
87