1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef _LINUX_KASAN_H 3 #define _LINUX_KASAN_H 4 5 #include <linux/types.h> 6 7 struct kmem_cache; 8 struct page; 9 struct vm_struct; 10 struct task_struct; 11 12 #ifdef CONFIG_KASAN 13 14 #include <asm/kasan.h> 15 #include <asm/pgtable.h> 16 17 extern unsigned char kasan_early_shadow_page[PAGE_SIZE]; 18 extern pte_t kasan_early_shadow_pte[PTRS_PER_PTE]; 19 extern pmd_t kasan_early_shadow_pmd[PTRS_PER_PMD]; 20 extern pud_t kasan_early_shadow_pud[PTRS_PER_PUD]; 21 extern p4d_t kasan_early_shadow_p4d[MAX_PTRS_PER_P4D]; 22 23 int kasan_populate_early_shadow(const void *shadow_start, 24 const void *shadow_end); 25 26 static inline void *kasan_mem_to_shadow(const void *addr) 27 { 28 return (void *)((unsigned long)addr >> KASAN_SHADOW_SCALE_SHIFT) 29 + KASAN_SHADOW_OFFSET; 30 } 31 32 /* Enable reporting bugs after kasan_disable_current() */ 33 extern void kasan_enable_current(void); 34 35 /* Disable reporting bugs for current task */ 36 extern void kasan_disable_current(void); 37 38 void kasan_unpoison_shadow(const void *address, size_t size); 39 40 void kasan_unpoison_task_stack(struct task_struct *task); 41 void kasan_unpoison_stack_above_sp_to(const void *watermark); 42 43 void kasan_alloc_pages(struct page *page, unsigned int order); 44 void kasan_free_pages(struct page *page, unsigned int order); 45 46 void kasan_cache_create(struct kmem_cache *cache, unsigned int *size, 47 slab_flags_t *flags); 48 49 void kasan_poison_slab(struct page *page); 50 void kasan_unpoison_object_data(struct kmem_cache *cache, void *object); 51 void kasan_poison_object_data(struct kmem_cache *cache, void *object); 52 void * __must_check kasan_init_slab_obj(struct kmem_cache *cache, 53 const void *object); 54 55 void * __must_check kasan_kmalloc_large(const void *ptr, size_t size, 56 gfp_t flags); 57 void kasan_kfree_large(void *ptr, unsigned long ip); 58 void kasan_poison_kfree(void *ptr, unsigned long ip); 59 void * __must_check kasan_kmalloc(struct kmem_cache *s, const void *object, 60 size_t size, gfp_t flags); 61 void * __must_check kasan_krealloc(const void *object, size_t new_size, 62 gfp_t flags); 63 64 void * __must_check kasan_slab_alloc(struct kmem_cache *s, void *object, 65 gfp_t flags); 66 bool kasan_slab_free(struct kmem_cache *s, void *object, unsigned long ip); 67 68 struct kasan_cache { 69 int alloc_meta_offset; 70 int free_meta_offset; 71 }; 72 73 /* 74 * These functions provide a special case to support backing module 75 * allocations with real shadow memory. With KASAN vmalloc, the special 76 * case is unnecessary, as the work is handled in the generic case. 77 */ 78 #ifndef CONFIG_KASAN_VMALLOC 79 int kasan_module_alloc(void *addr, size_t size); 80 void kasan_free_shadow(const struct vm_struct *vm); 81 #else 82 static inline int kasan_module_alloc(void *addr, size_t size) { return 0; } 83 static inline void kasan_free_shadow(const struct vm_struct *vm) {} 84 #endif 85 86 int kasan_add_zero_shadow(void *start, unsigned long size); 87 void kasan_remove_zero_shadow(void *start, unsigned long size); 88 89 size_t __ksize(const void *); 90 static inline void kasan_unpoison_slab(const void *ptr) 91 { 92 kasan_unpoison_shadow(ptr, __ksize(ptr)); 93 } 94 size_t kasan_metadata_size(struct kmem_cache *cache); 95 96 bool kasan_save_enable_multi_shot(void); 97 void kasan_restore_multi_shot(bool enabled); 98 99 #else /* CONFIG_KASAN */ 100 101 static inline void kasan_unpoison_shadow(const void *address, size_t size) {} 102 103 static inline void kasan_unpoison_task_stack(struct task_struct *task) {} 104 static inline void kasan_unpoison_stack_above_sp_to(const void *watermark) {} 105 106 static inline void kasan_enable_current(void) {} 107 static inline void kasan_disable_current(void) {} 108 109 static inline void kasan_alloc_pages(struct page *page, unsigned int order) {} 110 static inline void kasan_free_pages(struct page *page, unsigned int order) {} 111 112 static inline void kasan_cache_create(struct kmem_cache *cache, 113 unsigned int *size, 114 slab_flags_t *flags) {} 115 116 static inline void kasan_poison_slab(struct page *page) {} 117 static inline void kasan_unpoison_object_data(struct kmem_cache *cache, 118 void *object) {} 119 static inline void kasan_poison_object_data(struct kmem_cache *cache, 120 void *object) {} 121 static inline void *kasan_init_slab_obj(struct kmem_cache *cache, 122 const void *object) 123 { 124 return (void *)object; 125 } 126 127 static inline void *kasan_kmalloc_large(void *ptr, size_t size, gfp_t flags) 128 { 129 return ptr; 130 } 131 static inline void kasan_kfree_large(void *ptr, unsigned long ip) {} 132 static inline void kasan_poison_kfree(void *ptr, unsigned long ip) {} 133 static inline void *kasan_kmalloc(struct kmem_cache *s, const void *object, 134 size_t size, gfp_t flags) 135 { 136 return (void *)object; 137 } 138 static inline void *kasan_krealloc(const void *object, size_t new_size, 139 gfp_t flags) 140 { 141 return (void *)object; 142 } 143 144 static inline void *kasan_slab_alloc(struct kmem_cache *s, void *object, 145 gfp_t flags) 146 { 147 return object; 148 } 149 static inline bool kasan_slab_free(struct kmem_cache *s, void *object, 150 unsigned long ip) 151 { 152 return false; 153 } 154 155 static inline int kasan_module_alloc(void *addr, size_t size) { return 0; } 156 static inline void kasan_free_shadow(const struct vm_struct *vm) {} 157 158 static inline int kasan_add_zero_shadow(void *start, unsigned long size) 159 { 160 return 0; 161 } 162 static inline void kasan_remove_zero_shadow(void *start, 163 unsigned long size) 164 {} 165 166 static inline void kasan_unpoison_slab(const void *ptr) { } 167 static inline size_t kasan_metadata_size(struct kmem_cache *cache) { return 0; } 168 169 #endif /* CONFIG_KASAN */ 170 171 #ifdef CONFIG_KASAN_GENERIC 172 173 #define KASAN_SHADOW_INIT 0 174 175 void kasan_cache_shrink(struct kmem_cache *cache); 176 void kasan_cache_shutdown(struct kmem_cache *cache); 177 178 #else /* CONFIG_KASAN_GENERIC */ 179 180 static inline void kasan_cache_shrink(struct kmem_cache *cache) {} 181 static inline void kasan_cache_shutdown(struct kmem_cache *cache) {} 182 183 #endif /* CONFIG_KASAN_GENERIC */ 184 185 #ifdef CONFIG_KASAN_SW_TAGS 186 187 #define KASAN_SHADOW_INIT 0xFF 188 189 void kasan_init_tags(void); 190 191 void *kasan_reset_tag(const void *addr); 192 193 void kasan_report(unsigned long addr, size_t size, 194 bool is_write, unsigned long ip); 195 196 #else /* CONFIG_KASAN_SW_TAGS */ 197 198 static inline void kasan_init_tags(void) { } 199 200 static inline void *kasan_reset_tag(const void *addr) 201 { 202 return (void *)addr; 203 } 204 205 #endif /* CONFIG_KASAN_SW_TAGS */ 206 207 #ifdef CONFIG_KASAN_VMALLOC 208 int kasan_populate_vmalloc(unsigned long addr, unsigned long size); 209 void kasan_poison_vmalloc(const void *start, unsigned long size); 210 void kasan_unpoison_vmalloc(const void *start, unsigned long size); 211 void kasan_release_vmalloc(unsigned long start, unsigned long end, 212 unsigned long free_region_start, 213 unsigned long free_region_end); 214 #else 215 static inline int kasan_populate_vmalloc(unsigned long start, 216 unsigned long size) 217 { 218 return 0; 219 } 220 221 static inline void kasan_poison_vmalloc(const void *start, unsigned long size) 222 { } 223 static inline void kasan_unpoison_vmalloc(const void *start, unsigned long size) 224 { } 225 static inline void kasan_release_vmalloc(unsigned long start, 226 unsigned long end, 227 unsigned long free_region_start, 228 unsigned long free_region_end) {} 229 #endif 230 231 #endif /* LINUX_KASAN_H */ 232