include/linux/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 /*
  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 *) 0x200 + POISON_POINTER_DELTA)
  25
  26 /********** include/linux/timer.h **********/
  27 /*
  28  * Magic number "tsta" to indicate a static timer initializer
  29  * for the object debugging code.
  30  */
  31 #define TIMER_ENTRY_STATIC      ((void *) 0x300 + POISON_POINTER_DELTA)
  32
  33 /********** mm/debug-pagealloc.c **********/
  34 #ifdef CONFIG_PAGE_POISONING_ZERO
  35 #define PAGE_POISON 0x00
  36 #else
  37 #define PAGE_POISON 0xaa
  38 #endif
  39
  40 /********** mm/page_alloc.c ************/
  41
  42 #define TAIL_MAPPING    ((void *) 0x400 + POISON_POINTER_DELTA)
  43
  44 /********** mm/slab.c **********/
  45 /*
  46  * Magic nums for obj red zoning.
  47  * Placed in the first word before and the first word after an obj.
  48  */
  49 #define RED_INACTIVE    0x09F911029D74E35BULL   /* when obj is inactive */
  50 #define RED_ACTIVE      0xD84156C5635688C0ULL   /* when obj is active */
  51
  52 #define SLUB_RED_INACTIVE       0xbb
  53 #define SLUB_RED_ACTIVE         0xcc
  54
  55 /* ...and for poisoning */
  56 #define POISON_INUSE    0x5a    /* for use-uninitialised poisoning */
  57 #define POISON_FREE     0x6b    /* for use-after-free poisoning */
  58 #define POISON_END      0xa5    /* end-byte of poisoning */
  59
  60 /********** arch/$ARCH/mm/init.c **********/
  61 #define POISON_FREE_INITMEM     0xcc
  62
  63 /********** arch/ia64/hp/common/sba_iommu.c **********/
  64 /*
  65  * arch/ia64/hp/common/sba_iommu.c uses a 16-byte poison string with a
  66  * value of "SBAIOMMU POISON\0" for spill-over poisoning.
  67  */
  68
  69 /********** fs/jbd/journal.c **********/
  70 #define JBD_POISON_FREE         0x5b
  71 #define JBD2_POISON_FREE        0x5c
  72
  73 /********** drivers/base/dmapool.c **********/
  74 #define POOL_POISON_FREED       0xa7    /* !inuse */
  75 #define POOL_POISON_ALLOCATED   0xa9    /* !initted */
  76
  77 /********** drivers/atm/ **********/
  78 #define ATM_POISON_FREE         0x12
  79 #define ATM_POISON              0xdeadbeef
  80
  81 /********** kernel/mutexes **********/
  82 #define MUTEX_DEBUG_INIT        0x11
  83 #define MUTEX_DEBUG_FREE        0x22
  84 #define MUTEX_POISON_WW_CTX     ((void *) 0x500 + POISON_POINTER_DELTA)
  85
  86 /********** lib/flex_array.c **********/
  87 #define FLEX_ARRAY_FREE 0x6c    /* for use-after-free poisoning */
  88
  89 /********** security/ **********/
  90 #define KEY_DESTROY             0xbd
  91
  92 #endif