xref: /linux/include/linux/poison.h (revision e7d759f31ca295d589f7420719c311870bb3166f)
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 /********** net/ **********/
87 #define NET_PTR_POISON		((void *)(0x801 + POISON_POINTER_DELTA))
88 
89 /********** kernel/bpf/ **********/
90 #define BPF_PTR_POISON ((void *)(0xeB9FUL + POISON_POINTER_DELTA))
91 
92 /********** VFS **********/
93 #define VFS_PTR_POISON ((void *)(0xF5 + POISON_POINTER_DELTA))
94 
95 #endif
96