mm/kasan/kasan.h

   1 #ifndef __MM_KASAN_KASAN_H
   2 #define __MM_KASAN_KASAN_H
   3
   4 #include <linux/kasan.h>
   5
   6 #define KASAN_SHADOW_SCALE_SIZE (1UL << KASAN_SHADOW_SCALE_SHIFT)
   7 #define KASAN_SHADOW_MASK       (KASAN_SHADOW_SCALE_SIZE - 1)
   8
   9 #define KASAN_FREE_PAGE         0xFF  /* page was freed */
  10 #define KASAN_PAGE_REDZONE      0xFE  /* redzone for kmalloc_large allocations */
  11 #define KASAN_KMALLOC_REDZONE   0xFC  /* redzone inside slub object */
  12 #define KASAN_KMALLOC_FREE      0xFB  /* object was freed (kmem_cache_free/kfree) */
  13 #define KASAN_GLOBAL_REDZONE    0xFA  /* redzone for global variable */
  14
  15 /*
  16  * Stack redzone shadow values
  17  * (Those are compiler's ABI, don't change them)
  18  */
  19 #define KASAN_STACK_LEFT        0xF1
  20 #define KASAN_STACK_MID         0xF2
  21 #define KASAN_STACK_RIGHT       0xF3
  22 #define KASAN_STACK_PARTIAL     0xF4
  23
  24 /* Don't break randconfig/all*config builds */
  25 #ifndef KASAN_ABI_VERSION
  26 #define KASAN_ABI_VERSION 1
  27 #endif
  28
  29 struct kasan_access_info {
  30         const void *access_addr;
  31         const void *first_bad_addr;
  32         size_t access_size;
  33         bool is_write;
  34         unsigned long ip;
  35 };
  36
  37 /* The layout of struct dictated by compiler */
  38 struct kasan_source_location {
  39         const char *filename;
  40         int line_no;
  41         int column_no;
  42 };
  43
  44 /* The layout of struct dictated by compiler */
  45 struct kasan_global {
  46         const void *beg;                /* Address of the beginning of the global variable. */
  47         size_t size;                    /* Size of the global variable. */
  48         size_t size_with_redzone;       /* Size of the variable + size of the red zone. 32 bytes aligned */
  49         const void *name;
  50         const void *module_name;        /* Name of the module where the global variable is declared. */
  51         unsigned long has_dynamic_init; /* This needed for C++ */
  52 #if KASAN_ABI_VERSION >= 4
  53         struct kasan_source_location *location;
  54 #endif
  55 };
  56
  57 /**
  58  * Structures to keep alloc and free tracks *
  59  */
  60
  61 enum kasan_state {
  62         KASAN_STATE_INIT,
  63         KASAN_STATE_ALLOC,
  64         KASAN_STATE_FREE
  65 };
  66
  67 struct kasan_track {
  68         u64 cpu : 6;                    /* for NR_CPUS = 64 */
  69         u64 pid : 16;                   /* 65536 processes */
  70         u64 when : 42;                  /* ~140 years */
  71 };
  72
  73 struct kasan_alloc_meta {
  74         u32 state : 2;  /* enum kasan_state */
  75         u32 alloc_size : 30;
  76         struct kasan_track track;
  77 };
  78
  79 struct kasan_free_meta {
  80         /* Allocator freelist pointer, unused by KASAN. */
  81         void **freelist;
  82         struct kasan_track track;
  83 };
  84
  85 struct kasan_alloc_meta *get_alloc_info(struct kmem_cache *cache,
  86                                         const void *object);
  87 struct kasan_free_meta *get_free_info(struct kmem_cache *cache,
  88                                         const void *object);
  89
  90
  91 static inline const void *kasan_shadow_to_mem(const void *shadow_addr)
  92 {
  93         return (void *)(((unsigned long)shadow_addr - KASAN_SHADOW_OFFSET)
  94                 << KASAN_SHADOW_SCALE_SHIFT);
  95 }
  96
  97 static inline bool kasan_report_enabled(void)
  98 {
  99         return !current->kasan_depth;
 100 }
 101
 102 void kasan_report(unsigned long addr, size_t size,
 103                 bool is_write, unsigned long ip);
 104
 105 #endif