xref: /linux/include/linux/poison.h (revision 74ce1896c6c65b2f8cccbf59162d542988835835)
1 #ifndef _LINUX_POISON_H
2 #define _LINUX_POISON_H
3 
4 /********** include/linux/list.h **********/
5 
6 /*
7  * Architectures might want to move the poison pointer offset
8  * into some well-recognized area such as 0xdead000000000000,
9  * that is also not mappable by user-space exploits:
10  */
11 #ifdef CONFIG_ILLEGAL_POINTER_VALUE
12 # define POISON_POINTER_DELTA _AC(CONFIG_ILLEGAL_POINTER_VALUE, UL)
13 #else
14 # define POISON_POINTER_DELTA 0
15 #endif
16 
17 /*
18  * These are non-NULL pointers that will result in page faults
19  * under normal circumstances, used to verify that nobody uses
20  * non-initialized list entries.
21  */
22 #define LIST_POISON1  ((void *) 0x100 + POISON_POINTER_DELTA)
23 #define LIST_POISON2  ((void *) 0x200 + POISON_POINTER_DELTA)
24 
25 /********** include/linux/timer.h **********/
26 /*
27  * Magic number "tsta" to indicate a static timer initializer
28  * for the object debugging code.
29  */
30 #define TIMER_ENTRY_STATIC	((void *) 0x300 + POISON_POINTER_DELTA)
31 
32 /********** mm/debug-pagealloc.c **********/
33 #ifdef CONFIG_PAGE_POISONING_ZERO
34 #define PAGE_POISON 0x00
35 #else
36 #define PAGE_POISON 0xaa
37 #endif
38 
39 /********** mm/page_alloc.c ************/
40 
41 #define TAIL_MAPPING	((void *) 0x400 + POISON_POINTER_DELTA)
42 
43 /********** mm/slab.c **********/
44 /*
45  * Magic nums for obj red zoning.
46  * Placed in the first word before and the first word after an obj.
47  */
48 #define	RED_INACTIVE	0x09F911029D74E35BULL	/* when obj is inactive */
49 #define	RED_ACTIVE	0xD84156C5635688C0ULL	/* when obj is active */
50 
51 #define SLUB_RED_INACTIVE	0xbb
52 #define SLUB_RED_ACTIVE		0xcc
53 
54 /* ...and for poisoning */
55 #define	POISON_INUSE	0x5a	/* for use-uninitialised poisoning */
56 #define POISON_FREE	0x6b	/* for use-after-free poisoning */
57 #define	POISON_END	0xa5	/* end-byte of poisoning */
58 
59 /********** arch/$ARCH/mm/init.c **********/
60 #define POISON_FREE_INITMEM	0xcc
61 
62 /********** arch/ia64/hp/common/sba_iommu.c **********/
63 /*
64  * arch/ia64/hp/common/sba_iommu.c uses a 16-byte poison string with a
65  * value of "SBAIOMMU POISON\0" for spill-over poisoning.
66  */
67 
68 /********** fs/jbd/journal.c **********/
69 #define JBD_POISON_FREE		0x5b
70 #define JBD2_POISON_FREE	0x5c
71 
72 /********** drivers/base/dmapool.c **********/
73 #define	POOL_POISON_FREED	0xa7	/* !inuse */
74 #define	POOL_POISON_ALLOCATED	0xa9	/* !initted */
75 
76 /********** drivers/atm/ **********/
77 #define ATM_POISON_FREE		0x12
78 #define ATM_POISON		0xdeadbeef
79 
80 /********** kernel/mutexes **********/
81 #define MUTEX_DEBUG_INIT	0x11
82 #define MUTEX_DEBUG_FREE	0x22
83 #define MUTEX_POISON_WW_CTX	((void *) 0x500 + POISON_POINTER_DELTA)
84 
85 /********** lib/flex_array.c **********/
86 #define FLEX_ARRAY_FREE	0x6c	/* for use-after-free poisoning */
87 
88 /********** security/ **********/
89 #define KEY_DESTROY		0xbd
90 
91 #endif
92