1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _LINUX_KASAN_H
3 #define _LINUX_KASAN_H
4
5 #include <linux/bug.h>
6 #include <linux/kasan-enabled.h>
7 #include <linux/kernel.h>
8 #include <linux/static_key.h>
9 #include <linux/types.h>
10
11 struct kmem_cache;
12 struct page;
13 struct slab;
14 struct vm_struct;
15 struct task_struct;
16
17 #ifdef CONFIG_KASAN
18
19 #include <linux/linkage.h>
20 #include <asm/kasan.h>
21
22 #endif
23
24 typedef unsigned int __bitwise kasan_vmalloc_flags_t;
25
26 #define KASAN_VMALLOC_NONE ((__force kasan_vmalloc_flags_t)0x00u)
27 #define KASAN_VMALLOC_INIT ((__force kasan_vmalloc_flags_t)0x01u)
28 #define KASAN_VMALLOC_VM_ALLOC ((__force kasan_vmalloc_flags_t)0x02u)
29 #define KASAN_VMALLOC_PROT_NORMAL ((__force kasan_vmalloc_flags_t)0x04u)
30
31 #if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)
32
33 #include <linux/pgtable.h>
34
35 /* Software KASAN implementations use shadow memory. */
36
37 #ifdef CONFIG_KASAN_SW_TAGS
38 /* This matches KASAN_TAG_INVALID. */
39 #define KASAN_SHADOW_INIT 0xFE
40 #else
41 #define KASAN_SHADOW_INIT 0
42 #endif
43
44 #ifndef PTE_HWTABLE_PTRS
45 #define PTE_HWTABLE_PTRS 0
46 #endif
47
48 extern unsigned char kasan_early_shadow_page[PAGE_SIZE];
49 extern pte_t kasan_early_shadow_pte[MAX_PTRS_PER_PTE + PTE_HWTABLE_PTRS];
50 extern pmd_t kasan_early_shadow_pmd[MAX_PTRS_PER_PMD];
51 extern pud_t kasan_early_shadow_pud[MAX_PTRS_PER_PUD];
52 extern p4d_t kasan_early_shadow_p4d[MAX_PTRS_PER_P4D];
53
54 int kasan_populate_early_shadow(const void *shadow_start,
55 const void *shadow_end);
56
kasan_mem_to_shadow(const void * addr)57 static inline void *kasan_mem_to_shadow(const void *addr)
58 {
59 return (void *)((unsigned long)addr >> KASAN_SHADOW_SCALE_SHIFT)
60 + KASAN_SHADOW_OFFSET;
61 }
62
63 int kasan_add_zero_shadow(void *start, unsigned long size);
64 void kasan_remove_zero_shadow(void *start, unsigned long size);
65
66 /* Enable reporting bugs after kasan_disable_current() */
67 extern void kasan_enable_current(void);
68
69 /* Disable reporting bugs for current task */
70 extern void kasan_disable_current(void);
71
72 #else /* CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS */
73
kasan_add_zero_shadow(void * start,unsigned long size)74 static inline int kasan_add_zero_shadow(void *start, unsigned long size)
75 {
76 return 0;
77 }
kasan_remove_zero_shadow(void * start,unsigned long size)78 static inline void kasan_remove_zero_shadow(void *start,
79 unsigned long size)
80 {}
81
kasan_enable_current(void)82 static inline void kasan_enable_current(void) {}
kasan_disable_current(void)83 static inline void kasan_disable_current(void) {}
84
85 #endif /* CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS */
86
87 #ifdef CONFIG_KASAN_HW_TAGS
88
89 #else /* CONFIG_KASAN_HW_TAGS */
90
91 #endif /* CONFIG_KASAN_HW_TAGS */
92
kasan_has_integrated_init(void)93 static inline bool kasan_has_integrated_init(void)
94 {
95 return kasan_hw_tags_enabled();
96 }
97
98 #ifdef CONFIG_KASAN
99
100 struct kasan_cache {
101 #ifdef CONFIG_KASAN_GENERIC
102 int alloc_meta_offset;
103 int free_meta_offset;
104 #endif
105 bool is_kmalloc;
106 };
107
108 void __kasan_unpoison_range(const void *addr, size_t size);
kasan_unpoison_range(const void * addr,size_t size)109 static __always_inline void kasan_unpoison_range(const void *addr, size_t size)
110 {
111 if (kasan_enabled())
112 __kasan_unpoison_range(addr, size);
113 }
114
115 void __kasan_poison_pages(struct page *page, unsigned int order, bool init);
kasan_poison_pages(struct page * page,unsigned int order,bool init)116 static __always_inline void kasan_poison_pages(struct page *page,
117 unsigned int order, bool init)
118 {
119 if (kasan_enabled())
120 __kasan_poison_pages(page, order, init);
121 }
122
123 void __kasan_unpoison_pages(struct page *page, unsigned int order, bool init);
kasan_unpoison_pages(struct page * page,unsigned int order,bool init)124 static __always_inline void kasan_unpoison_pages(struct page *page,
125 unsigned int order, bool init)
126 {
127 if (kasan_enabled())
128 __kasan_unpoison_pages(page, order, init);
129 }
130
131 void __kasan_cache_create_kmalloc(struct kmem_cache *cache);
kasan_cache_create_kmalloc(struct kmem_cache * cache)132 static __always_inline void kasan_cache_create_kmalloc(struct kmem_cache *cache)
133 {
134 if (kasan_enabled())
135 __kasan_cache_create_kmalloc(cache);
136 }
137
138 void __kasan_poison_slab(struct slab *slab);
kasan_poison_slab(struct slab * slab)139 static __always_inline void kasan_poison_slab(struct slab *slab)
140 {
141 if (kasan_enabled())
142 __kasan_poison_slab(slab);
143 }
144
145 void __kasan_unpoison_object_data(struct kmem_cache *cache, void *object);
kasan_unpoison_object_data(struct kmem_cache * cache,void * object)146 static __always_inline void kasan_unpoison_object_data(struct kmem_cache *cache,
147 void *object)
148 {
149 if (kasan_enabled())
150 __kasan_unpoison_object_data(cache, object);
151 }
152
153 void __kasan_poison_object_data(struct kmem_cache *cache, void *object);
kasan_poison_object_data(struct kmem_cache * cache,void * object)154 static __always_inline void kasan_poison_object_data(struct kmem_cache *cache,
155 void *object)
156 {
157 if (kasan_enabled())
158 __kasan_poison_object_data(cache, object);
159 }
160
161 void * __must_check __kasan_init_slab_obj(struct kmem_cache *cache,
162 const void *object);
kasan_init_slab_obj(struct kmem_cache * cache,const void * object)163 static __always_inline void * __must_check kasan_init_slab_obj(
164 struct kmem_cache *cache, const void *object)
165 {
166 if (kasan_enabled())
167 return __kasan_init_slab_obj(cache, object);
168 return (void *)object;
169 }
170
171 bool __kasan_slab_free(struct kmem_cache *s, void *object,
172 unsigned long ip, bool init);
kasan_slab_free(struct kmem_cache * s,void * object,bool init)173 static __always_inline bool kasan_slab_free(struct kmem_cache *s,
174 void *object, bool init)
175 {
176 if (kasan_enabled())
177 return __kasan_slab_free(s, object, _RET_IP_, init);
178 return false;
179 }
180
181 void __kasan_kfree_large(void *ptr, unsigned long ip);
kasan_kfree_large(void * ptr)182 static __always_inline void kasan_kfree_large(void *ptr)
183 {
184 if (kasan_enabled())
185 __kasan_kfree_large(ptr, _RET_IP_);
186 }
187
188 void __kasan_slab_free_mempool(void *ptr, unsigned long ip);
kasan_slab_free_mempool(void * ptr)189 static __always_inline void kasan_slab_free_mempool(void *ptr)
190 {
191 if (kasan_enabled())
192 __kasan_slab_free_mempool(ptr, _RET_IP_);
193 }
194
195 void * __must_check __kasan_slab_alloc(struct kmem_cache *s,
196 void *object, gfp_t flags, bool init);
kasan_slab_alloc(struct kmem_cache * s,void * object,gfp_t flags,bool init)197 static __always_inline void * __must_check kasan_slab_alloc(
198 struct kmem_cache *s, void *object, gfp_t flags, bool init)
199 {
200 if (kasan_enabled())
201 return __kasan_slab_alloc(s, object, flags, init);
202 return object;
203 }
204
205 void * __must_check __kasan_kmalloc(struct kmem_cache *s, const void *object,
206 size_t size, gfp_t flags);
kasan_kmalloc(struct kmem_cache * s,const void * object,size_t size,gfp_t flags)207 static __always_inline void * __must_check kasan_kmalloc(struct kmem_cache *s,
208 const void *object, size_t size, gfp_t flags)
209 {
210 if (kasan_enabled())
211 return __kasan_kmalloc(s, object, size, flags);
212 return (void *)object;
213 }
214
215 void * __must_check __kasan_kmalloc_large(const void *ptr,
216 size_t size, gfp_t flags);
kasan_kmalloc_large(const void * ptr,size_t size,gfp_t flags)217 static __always_inline void * __must_check kasan_kmalloc_large(const void *ptr,
218 size_t size, gfp_t flags)
219 {
220 if (kasan_enabled())
221 return __kasan_kmalloc_large(ptr, size, flags);
222 return (void *)ptr;
223 }
224
225 void * __must_check __kasan_krealloc(const void *object,
226 size_t new_size, gfp_t flags);
kasan_krealloc(const void * object,size_t new_size,gfp_t flags)227 static __always_inline void * __must_check kasan_krealloc(const void *object,
228 size_t new_size, gfp_t flags)
229 {
230 if (kasan_enabled())
231 return __kasan_krealloc(object, new_size, flags);
232 return (void *)object;
233 }
234
235 /*
236 * Unlike kasan_check_read/write(), kasan_check_byte() is performed even for
237 * the hardware tag-based mode that doesn't rely on compiler instrumentation.
238 */
239 bool __kasan_check_byte(const void *addr, unsigned long ip);
kasan_check_byte(const void * addr)240 static __always_inline bool kasan_check_byte(const void *addr)
241 {
242 if (kasan_enabled())
243 return __kasan_check_byte(addr, _RET_IP_);
244 return true;
245 }
246
247 #else /* CONFIG_KASAN */
248
kasan_unpoison_range(const void * address,size_t size)249 static inline void kasan_unpoison_range(const void *address, size_t size) {}
kasan_poison_pages(struct page * page,unsigned int order,bool init)250 static inline void kasan_poison_pages(struct page *page, unsigned int order,
251 bool init) {}
kasan_unpoison_pages(struct page * page,unsigned int order,bool init)252 static inline void kasan_unpoison_pages(struct page *page, unsigned int order,
253 bool init) {}
kasan_cache_create_kmalloc(struct kmem_cache * cache)254 static inline void kasan_cache_create_kmalloc(struct kmem_cache *cache) {}
kasan_poison_slab(struct slab * slab)255 static inline void kasan_poison_slab(struct slab *slab) {}
kasan_unpoison_object_data(struct kmem_cache * cache,void * object)256 static inline void kasan_unpoison_object_data(struct kmem_cache *cache,
257 void *object) {}
kasan_poison_object_data(struct kmem_cache * cache,void * object)258 static inline void kasan_poison_object_data(struct kmem_cache *cache,
259 void *object) {}
kasan_init_slab_obj(struct kmem_cache * cache,const void * object)260 static inline void *kasan_init_slab_obj(struct kmem_cache *cache,
261 const void *object)
262 {
263 return (void *)object;
264 }
kasan_slab_free(struct kmem_cache * s,void * object,bool init)265 static inline bool kasan_slab_free(struct kmem_cache *s, void *object, bool init)
266 {
267 return false;
268 }
kasan_kfree_large(void * ptr)269 static inline void kasan_kfree_large(void *ptr) {}
kasan_slab_free_mempool(void * ptr)270 static inline void kasan_slab_free_mempool(void *ptr) {}
kasan_slab_alloc(struct kmem_cache * s,void * object,gfp_t flags,bool init)271 static inline void *kasan_slab_alloc(struct kmem_cache *s, void *object,
272 gfp_t flags, bool init)
273 {
274 return object;
275 }
kasan_kmalloc(struct kmem_cache * s,const void * object,size_t size,gfp_t flags)276 static inline void *kasan_kmalloc(struct kmem_cache *s, const void *object,
277 size_t size, gfp_t flags)
278 {
279 return (void *)object;
280 }
kasan_kmalloc_large(const void * ptr,size_t size,gfp_t flags)281 static inline void *kasan_kmalloc_large(const void *ptr, size_t size, gfp_t flags)
282 {
283 return (void *)ptr;
284 }
kasan_krealloc(const void * object,size_t new_size,gfp_t flags)285 static inline void *kasan_krealloc(const void *object, size_t new_size,
286 gfp_t flags)
287 {
288 return (void *)object;
289 }
kasan_check_byte(const void * address)290 static inline bool kasan_check_byte(const void *address)
291 {
292 return true;
293 }
294
295 #endif /* CONFIG_KASAN */
296
297 #if defined(CONFIG_KASAN) && defined(CONFIG_KASAN_STACK)
298 void kasan_unpoison_task_stack(struct task_struct *task);
299 #else
kasan_unpoison_task_stack(struct task_struct * task)300 static inline void kasan_unpoison_task_stack(struct task_struct *task) {}
301 #endif
302
303 #ifdef CONFIG_KASAN_GENERIC
304
305 size_t kasan_metadata_size(struct kmem_cache *cache);
306 slab_flags_t kasan_never_merge(void);
307 void kasan_cache_create(struct kmem_cache *cache, unsigned int *size,
308 slab_flags_t *flags);
309
310 void kasan_cache_shrink(struct kmem_cache *cache);
311 void kasan_cache_shutdown(struct kmem_cache *cache);
312 void kasan_record_aux_stack(void *ptr);
313 void kasan_record_aux_stack_noalloc(void *ptr);
314
315 #else /* CONFIG_KASAN_GENERIC */
316
317 /* Tag-based KASAN modes do not use per-object metadata. */
kasan_metadata_size(struct kmem_cache * cache)318 static inline size_t kasan_metadata_size(struct kmem_cache *cache)
319 {
320 return 0;
321 }
322 /* And thus nothing prevents cache merging. */
kasan_never_merge(void)323 static inline slab_flags_t kasan_never_merge(void)
324 {
325 return 0;
326 }
327 /* And no cache-related metadata initialization is required. */
kasan_cache_create(struct kmem_cache * cache,unsigned int * size,slab_flags_t * flags)328 static inline void kasan_cache_create(struct kmem_cache *cache,
329 unsigned int *size,
330 slab_flags_t *flags) {}
331
kasan_cache_shrink(struct kmem_cache * cache)332 static inline void kasan_cache_shrink(struct kmem_cache *cache) {}
kasan_cache_shutdown(struct kmem_cache * cache)333 static inline void kasan_cache_shutdown(struct kmem_cache *cache) {}
kasan_record_aux_stack(void * ptr)334 static inline void kasan_record_aux_stack(void *ptr) {}
kasan_record_aux_stack_noalloc(void * ptr)335 static inline void kasan_record_aux_stack_noalloc(void *ptr) {}
336
337 #endif /* CONFIG_KASAN_GENERIC */
338
339 #if defined(CONFIG_KASAN_SW_TAGS) || defined(CONFIG_KASAN_HW_TAGS)
340
kasan_reset_tag(const void * addr)341 static inline void *kasan_reset_tag(const void *addr)
342 {
343 return (void *)arch_kasan_reset_tag(addr);
344 }
345
346 /**
347 * kasan_report - print a report about a bad memory access detected by KASAN
348 * @addr: address of the bad access
349 * @size: size of the bad access
350 * @is_write: whether the bad access is a write or a read
351 * @ip: instruction pointer for the accessibility check or the bad access itself
352 */
353 bool kasan_report(unsigned long addr, size_t size,
354 bool is_write, unsigned long ip);
355
356 #else /* CONFIG_KASAN_SW_TAGS || CONFIG_KASAN_HW_TAGS */
357
kasan_reset_tag(const void * addr)358 static inline void *kasan_reset_tag(const void *addr)
359 {
360 return (void *)addr;
361 }
362
363 #endif /* CONFIG_KASAN_SW_TAGS || CONFIG_KASAN_HW_TAGS*/
364
365 #ifdef CONFIG_KASAN_HW_TAGS
366
367 void kasan_report_async(void);
368
369 #endif /* CONFIG_KASAN_HW_TAGS */
370
371 #ifdef CONFIG_KASAN_SW_TAGS
372 void __init kasan_init_sw_tags(void);
373 #else
kasan_init_sw_tags(void)374 static inline void kasan_init_sw_tags(void) { }
375 #endif
376
377 #ifdef CONFIG_KASAN_HW_TAGS
378 void kasan_init_hw_tags_cpu(void);
379 void __init kasan_init_hw_tags(void);
380 #else
kasan_init_hw_tags_cpu(void)381 static inline void kasan_init_hw_tags_cpu(void) { }
kasan_init_hw_tags(void)382 static inline void kasan_init_hw_tags(void) { }
383 #endif
384
385 #ifdef CONFIG_KASAN_VMALLOC
386
387 #if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)
388
389 void kasan_populate_early_vm_area_shadow(void *start, unsigned long size);
390 int kasan_populate_vmalloc(unsigned long addr, unsigned long size);
391 void kasan_release_vmalloc(unsigned long start, unsigned long end,
392 unsigned long free_region_start,
393 unsigned long free_region_end);
394
395 #else /* CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS */
396
kasan_populate_early_vm_area_shadow(void * start,unsigned long size)397 static inline void kasan_populate_early_vm_area_shadow(void *start,
398 unsigned long size)
399 { }
kasan_populate_vmalloc(unsigned long start,unsigned long size)400 static inline int kasan_populate_vmalloc(unsigned long start,
401 unsigned long size)
402 {
403 return 0;
404 }
kasan_release_vmalloc(unsigned long start,unsigned long end,unsigned long free_region_start,unsigned long free_region_end)405 static inline void kasan_release_vmalloc(unsigned long start,
406 unsigned long end,
407 unsigned long free_region_start,
408 unsigned long free_region_end) { }
409
410 #endif /* CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS */
411
412 void *__kasan_unpoison_vmalloc(const void *start, unsigned long size,
413 kasan_vmalloc_flags_t flags);
kasan_unpoison_vmalloc(const void * start,unsigned long size,kasan_vmalloc_flags_t flags)414 static __always_inline void *kasan_unpoison_vmalloc(const void *start,
415 unsigned long size,
416 kasan_vmalloc_flags_t flags)
417 {
418 if (kasan_enabled())
419 return __kasan_unpoison_vmalloc(start, size, flags);
420 return (void *)start;
421 }
422
423 void __kasan_poison_vmalloc(const void *start, unsigned long size);
kasan_poison_vmalloc(const void * start,unsigned long size)424 static __always_inline void kasan_poison_vmalloc(const void *start,
425 unsigned long size)
426 {
427 if (kasan_enabled())
428 __kasan_poison_vmalloc(start, size);
429 }
430
431 #else /* CONFIG_KASAN_VMALLOC */
432
kasan_populate_early_vm_area_shadow(void * start,unsigned long size)433 static inline void kasan_populate_early_vm_area_shadow(void *start,
434 unsigned long size) { }
kasan_populate_vmalloc(unsigned long start,unsigned long size)435 static inline int kasan_populate_vmalloc(unsigned long start,
436 unsigned long size)
437 {
438 return 0;
439 }
kasan_release_vmalloc(unsigned long start,unsigned long end,unsigned long free_region_start,unsigned long free_region_end)440 static inline void kasan_release_vmalloc(unsigned long start,
441 unsigned long end,
442 unsigned long free_region_start,
443 unsigned long free_region_end) { }
444
kasan_unpoison_vmalloc(const void * start,unsigned long size,kasan_vmalloc_flags_t flags)445 static inline void *kasan_unpoison_vmalloc(const void *start,
446 unsigned long size,
447 kasan_vmalloc_flags_t flags)
448 {
449 return (void *)start;
450 }
kasan_poison_vmalloc(const void * start,unsigned long size)451 static inline void kasan_poison_vmalloc(const void *start, unsigned long size)
452 { }
453
454 #endif /* CONFIG_KASAN_VMALLOC */
455
456 #if (defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)) && \
457 !defined(CONFIG_KASAN_VMALLOC)
458
459 /*
460 * These functions allocate and free shadow memory for kernel modules.
461 * They are only required when KASAN_VMALLOC is not supported, as otherwise
462 * shadow memory is allocated by the generic vmalloc handlers.
463 */
464 int kasan_alloc_module_shadow(void *addr, size_t size, gfp_t gfp_mask);
465 void kasan_free_module_shadow(const struct vm_struct *vm);
466
467 #else /* (CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS) && !CONFIG_KASAN_VMALLOC */
468
kasan_alloc_module_shadow(void * addr,size_t size,gfp_t gfp_mask)469 static inline int kasan_alloc_module_shadow(void *addr, size_t size, gfp_t gfp_mask) { return 0; }
kasan_free_module_shadow(const struct vm_struct * vm)470 static inline void kasan_free_module_shadow(const struct vm_struct *vm) {}
471
472 #endif /* (CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS) && !CONFIG_KASAN_VMALLOC */
473
474 #ifdef CONFIG_KASAN_INLINE
475 void kasan_non_canonical_hook(unsigned long addr);
476 #else /* CONFIG_KASAN_INLINE */
kasan_non_canonical_hook(unsigned long addr)477 static inline void kasan_non_canonical_hook(unsigned long addr) { }
478 #endif /* CONFIG_KASAN_INLINE */
479
480 #endif /* LINUX_KASAN_H */
481