mm/kasan/kasan.h

   1 #ifndef __MM_KASAN_KASAN_H
   2 #define __MM_KASAN_KASAN_H
   3
   4 #include <linux/kasan.h>
   5 #include <linux/stackdepot.h>
   6
   7 #define KASAN_SHADOW_SCALE_SIZE (1UL << KASAN_SHADOW_SCALE_SHIFT)
   8 #define KASAN_SHADOW_MASK       (KASAN_SHADOW_SCALE_SIZE - 1)
   9
  10 #define KASAN_FREE_PAGE         0xFF  /* page was freed */
  11 #define KASAN_PAGE_REDZONE      0xFE  /* redzone for kmalloc_large allocations */
  12 #define KASAN_KMALLOC_REDZONE   0xFC  /* redzone inside slub object */
  13 #define KASAN_KMALLOC_FREE      0xFB  /* object was freed (kmem_cache_free/kfree) */
  14 #define KASAN_GLOBAL_REDZONE    0xFA  /* redzone for global variable */
  15
  16 /*
  17  * Stack redzone shadow values
  18  * (Those are compiler's ABI, don't change them)
  19  */
  20 #define KASAN_STACK_LEFT        0xF1
  21 #define KASAN_STACK_MID         0xF2
  22 #define KASAN_STACK_RIGHT       0xF3
  23 #define KASAN_STACK_PARTIAL     0xF4
  24
  25 /* Don't break randconfig/all*config builds */
  26 #ifndef KASAN_ABI_VERSION
  27 #define KASAN_ABI_VERSION 1
  28 #endif
  29
  30 struct kasan_access_info {
  31         const void *access_addr;
  32         const void *first_bad_addr;
  33         size_t access_size;
  34         bool is_write;
  35         unsigned long ip;
  36 };
  37
  38 /* The layout of struct dictated by compiler */
  39 struct kasan_source_location {
  40         const char *filename;
  41         int line_no;
  42         int column_no;
  43 };
  44
  45 /* The layout of struct dictated by compiler */
  46 struct kasan_global {
  47         const void *beg;                /* Address of the beginning of the global variable. */
  48         size_t size;                    /* Size of the global variable. */
  49         size_t size_with_redzone;       /* Size of the variable + size of the red zone. 32 bytes aligned */
  50         const void *name;
  51         const void *module_name;        /* Name of the module where the global variable is declared. */
  52         unsigned long has_dynamic_init; /* This needed for C++ */
  53 #if KASAN_ABI_VERSION >= 4
  54         struct kasan_source_location *location;
  55 #endif
  56 };
  57
  58 /**
  59  * Structures to keep alloc and free tracks *
  60  */
  61
  62 enum kasan_state {
  63         KASAN_STATE_INIT,
  64         KASAN_STATE_ALLOC,
  65         KASAN_STATE_FREE
  66 };
  67
  68 #define KASAN_STACK_DEPTH 64
  69
  70 struct kasan_track {
  71         u32 pid;
  72         depot_stack_handle_t stack;
  73 };
  74
  75 struct kasan_alloc_meta {
  76         struct kasan_track track;
  77         u32 state : 2;  /* enum kasan_state */
  78         u32 alloc_size : 30;
  79         u32 reserved;
  80 };
  81
  82 struct kasan_free_meta {
  83         /* Allocator freelist pointer, unused by KASAN. */
  84         void **freelist;
  85         struct kasan_track track;
  86 };
  87
  88 struct kasan_alloc_meta *get_alloc_info(struct kmem_cache *cache,
  89                                         const void *object);
  90 struct kasan_free_meta *get_free_info(struct kmem_cache *cache,
  91                                         const void *object);
  92
  93
  94 static inline const void *kasan_shadow_to_mem(const void *shadow_addr)
  95 {
  96         return (void *)(((unsigned long)shadow_addr - KASAN_SHADOW_OFFSET)
  97                 << KASAN_SHADOW_SCALE_SHIFT);
  98 }
  99
 100 static inline bool kasan_report_enabled(void)
 101 {
 102         return !current->kasan_depth;
 103 }
 104
 105 void kasan_report(unsigned long addr, size_t size,
 106                 bool is_write, unsigned long ip);
 107
 108 #endif