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 int alloc_meta_offset;
102 int free_meta_offset;
103 bool is_kmalloc;
104 };
105
106 slab_flags_t __kasan_never_merge(void);
kasan_never_merge(void)107 static __always_inline slab_flags_t kasan_never_merge(void)
108 {
109 if (kasan_enabled())
110 return __kasan_never_merge();
111 return 0;
112 }
113
114 void __kasan_unpoison_range(const void *addr, size_t size);
kasan_unpoison_range(const void * addr,size_t size)115 static __always_inline void kasan_unpoison_range(const void *addr, size_t size)
116 {
117 if (kasan_enabled())
118 __kasan_unpoison_range(addr, size);
119 }
120
121 void __kasan_poison_pages(struct page *page, unsigned int order, bool init);
kasan_poison_pages(struct page * page,unsigned int order,bool init)122 static __always_inline void kasan_poison_pages(struct page *page,
123 unsigned int order, bool init)
124 {
125 if (kasan_enabled())
126 __kasan_poison_pages(page, order, init);
127 }
128
129 void __kasan_unpoison_pages(struct page *page, unsigned int order, bool init);
kasan_unpoison_pages(struct page * page,unsigned int order,bool init)130 static __always_inline void kasan_unpoison_pages(struct page *page,
131 unsigned int order, bool init)
132 {
133 if (kasan_enabled())
134 __kasan_unpoison_pages(page, order, init);
135 }
136
137 void __kasan_cache_create(struct kmem_cache *cache, unsigned int *size,
138 slab_flags_t *flags);
kasan_cache_create(struct kmem_cache * cache,unsigned int * size,slab_flags_t * flags)139 static __always_inline void kasan_cache_create(struct kmem_cache *cache,
140 unsigned int *size, slab_flags_t *flags)
141 {
142 if (kasan_enabled())
143 __kasan_cache_create(cache, size, flags);
144 }
145
146 void __kasan_cache_create_kmalloc(struct kmem_cache *cache);
kasan_cache_create_kmalloc(struct kmem_cache * cache)147 static __always_inline void kasan_cache_create_kmalloc(struct kmem_cache *cache)
148 {
149 if (kasan_enabled())
150 __kasan_cache_create_kmalloc(cache);
151 }
152
153 size_t __kasan_metadata_size(struct kmem_cache *cache);
kasan_metadata_size(struct kmem_cache * cache)154 static __always_inline size_t kasan_metadata_size(struct kmem_cache *cache)
155 {
156 if (kasan_enabled())
157 return __kasan_metadata_size(cache);
158 return 0;
159 }
160
161 void __kasan_poison_slab(struct slab *slab);
kasan_poison_slab(struct slab * slab)162 static __always_inline void kasan_poison_slab(struct slab *slab)
163 {
164 if (kasan_enabled())
165 __kasan_poison_slab(slab);
166 }
167
168 void __kasan_unpoison_object_data(struct kmem_cache *cache, void *object);
kasan_unpoison_object_data(struct kmem_cache * cache,void * object)169 static __always_inline void kasan_unpoison_object_data(struct kmem_cache *cache,
170 void *object)
171 {
172 if (kasan_enabled())
173 __kasan_unpoison_object_data(cache, object);
174 }
175
176 void __kasan_poison_object_data(struct kmem_cache *cache, void *object);
kasan_poison_object_data(struct kmem_cache * cache,void * object)177 static __always_inline void kasan_poison_object_data(struct kmem_cache *cache,
178 void *object)
179 {
180 if (kasan_enabled())
181 __kasan_poison_object_data(cache, object);
182 }
183
184 void * __must_check __kasan_init_slab_obj(struct kmem_cache *cache,
185 const void *object);
kasan_init_slab_obj(struct kmem_cache * cache,const void * object)186 static __always_inline void * __must_check kasan_init_slab_obj(
187 struct kmem_cache *cache, const void *object)
188 {
189 if (kasan_enabled())
190 return __kasan_init_slab_obj(cache, object);
191 return (void *)object;
192 }
193
194 bool __kasan_slab_free(struct kmem_cache *s, void *object,
195 unsigned long ip, bool init);
kasan_slab_free(struct kmem_cache * s,void * object,bool init)196 static __always_inline bool kasan_slab_free(struct kmem_cache *s,
197 void *object, bool init)
198 {
199 if (kasan_enabled())
200 return __kasan_slab_free(s, object, _RET_IP_, init);
201 return false;
202 }
203
204 void __kasan_kfree_large(void *ptr, unsigned long ip);
kasan_kfree_large(void * ptr)205 static __always_inline void kasan_kfree_large(void *ptr)
206 {
207 if (kasan_enabled())
208 __kasan_kfree_large(ptr, _RET_IP_);
209 }
210
211 void __kasan_slab_free_mempool(void *ptr, unsigned long ip);
kasan_slab_free_mempool(void * ptr)212 static __always_inline void kasan_slab_free_mempool(void *ptr)
213 {
214 if (kasan_enabled())
215 __kasan_slab_free_mempool(ptr, _RET_IP_);
216 }
217
218 void * __must_check __kasan_slab_alloc(struct kmem_cache *s,
219 void *object, gfp_t flags, bool init);
kasan_slab_alloc(struct kmem_cache * s,void * object,gfp_t flags,bool init)220 static __always_inline void * __must_check kasan_slab_alloc(
221 struct kmem_cache *s, void *object, gfp_t flags, bool init)
222 {
223 if (kasan_enabled())
224 return __kasan_slab_alloc(s, object, flags, init);
225 return object;
226 }
227
228 void * __must_check __kasan_kmalloc(struct kmem_cache *s, const void *object,
229 size_t size, gfp_t flags);
kasan_kmalloc(struct kmem_cache * s,const void * object,size_t size,gfp_t flags)230 static __always_inline void * __must_check kasan_kmalloc(struct kmem_cache *s,
231 const void *object, size_t size, gfp_t flags)
232 {
233 if (kasan_enabled())
234 return __kasan_kmalloc(s, object, size, flags);
235 return (void *)object;
236 }
237
238 void * __must_check __kasan_kmalloc_large(const void *ptr,
239 size_t size, gfp_t flags);
kasan_kmalloc_large(const void * ptr,size_t size,gfp_t flags)240 static __always_inline void * __must_check kasan_kmalloc_large(const void *ptr,
241 size_t size, gfp_t flags)
242 {
243 if (kasan_enabled())
244 return __kasan_kmalloc_large(ptr, size, flags);
245 return (void *)ptr;
246 }
247
248 void * __must_check __kasan_krealloc(const void *object,
249 size_t new_size, gfp_t flags);
kasan_krealloc(const void * object,size_t new_size,gfp_t flags)250 static __always_inline void * __must_check kasan_krealloc(const void *object,
251 size_t new_size, gfp_t flags)
252 {
253 if (kasan_enabled())
254 return __kasan_krealloc(object, new_size, flags);
255 return (void *)object;
256 }
257
258 /*
259 * Unlike kasan_check_read/write(), kasan_check_byte() is performed even for
260 * the hardware tag-based mode that doesn't rely on compiler instrumentation.
261 */
262 bool __kasan_check_byte(const void *addr, unsigned long ip);
kasan_check_byte(const void * addr)263 static __always_inline bool kasan_check_byte(const void *addr)
264 {
265 if (kasan_enabled())
266 return __kasan_check_byte(addr, _RET_IP_);
267 return true;
268 }
269
270 #else /* CONFIG_KASAN */
271
kasan_never_merge(void)272 static inline slab_flags_t kasan_never_merge(void)
273 {
274 return 0;
275 }
kasan_unpoison_range(const void * address,size_t size)276 static inline void kasan_unpoison_range(const void *address, size_t size) {}
kasan_poison_pages(struct page * page,unsigned int order,bool init)277 static inline void kasan_poison_pages(struct page *page, unsigned int order,
278 bool init) {}
kasan_unpoison_pages(struct page * page,unsigned int order,bool init)279 static inline void kasan_unpoison_pages(struct page *page, unsigned int order,
280 bool init) {}
kasan_cache_create(struct kmem_cache * cache,unsigned int * size,slab_flags_t * flags)281 static inline void kasan_cache_create(struct kmem_cache *cache,
282 unsigned int *size,
283 slab_flags_t *flags) {}
kasan_cache_create_kmalloc(struct kmem_cache * cache)284 static inline void kasan_cache_create_kmalloc(struct kmem_cache *cache) {}
kasan_metadata_size(struct kmem_cache * cache)285 static inline size_t kasan_metadata_size(struct kmem_cache *cache) { return 0; }
kasan_poison_slab(struct slab * slab)286 static inline void kasan_poison_slab(struct slab *slab) {}
kasan_unpoison_object_data(struct kmem_cache * cache,void * object)287 static inline void kasan_unpoison_object_data(struct kmem_cache *cache,
288 void *object) {}
kasan_poison_object_data(struct kmem_cache * cache,void * object)289 static inline void kasan_poison_object_data(struct kmem_cache *cache,
290 void *object) {}
kasan_init_slab_obj(struct kmem_cache * cache,const void * object)291 static inline void *kasan_init_slab_obj(struct kmem_cache *cache,
292 const void *object)
293 {
294 return (void *)object;
295 }
kasan_slab_free(struct kmem_cache * s,void * object,bool init)296 static inline bool kasan_slab_free(struct kmem_cache *s, void *object, bool init)
297 {
298 return false;
299 }
kasan_kfree_large(void * ptr)300 static inline void kasan_kfree_large(void *ptr) {}
kasan_slab_free_mempool(void * ptr)301 static inline void kasan_slab_free_mempool(void *ptr) {}
kasan_slab_alloc(struct kmem_cache * s,void * object,gfp_t flags,bool init)302 static inline void *kasan_slab_alloc(struct kmem_cache *s, void *object,
303 gfp_t flags, bool init)
304 {
305 return object;
306 }
kasan_kmalloc(struct kmem_cache * s,const void * object,size_t size,gfp_t flags)307 static inline void *kasan_kmalloc(struct kmem_cache *s, const void *object,
308 size_t size, gfp_t flags)
309 {
310 return (void *)object;
311 }
kasan_kmalloc_large(const void * ptr,size_t size,gfp_t flags)312 static inline void *kasan_kmalloc_large(const void *ptr, size_t size, gfp_t flags)
313 {
314 return (void *)ptr;
315 }
kasan_krealloc(const void * object,size_t new_size,gfp_t flags)316 static inline void *kasan_krealloc(const void *object, size_t new_size,
317 gfp_t flags)
318 {
319 return (void *)object;
320 }
kasan_check_byte(const void * address)321 static inline bool kasan_check_byte(const void *address)
322 {
323 return true;
324 }
325
326 #endif /* CONFIG_KASAN */
327
328 #if defined(CONFIG_KASAN) && defined(CONFIG_KASAN_STACK)
329 void kasan_unpoison_task_stack(struct task_struct *task);
330 #else
kasan_unpoison_task_stack(struct task_struct * task)331 static inline void kasan_unpoison_task_stack(struct task_struct *task) {}
332 #endif
333
334 #ifdef CONFIG_KASAN_GENERIC
335
336 void kasan_cache_shrink(struct kmem_cache *cache);
337 void kasan_cache_shutdown(struct kmem_cache *cache);
338 void kasan_record_aux_stack(void *ptr);
339 void kasan_record_aux_stack_noalloc(void *ptr);
340
341 #else /* CONFIG_KASAN_GENERIC */
342
kasan_cache_shrink(struct kmem_cache * cache)343 static inline void kasan_cache_shrink(struct kmem_cache *cache) {}
kasan_cache_shutdown(struct kmem_cache * cache)344 static inline void kasan_cache_shutdown(struct kmem_cache *cache) {}
kasan_record_aux_stack(void * ptr)345 static inline void kasan_record_aux_stack(void *ptr) {}
kasan_record_aux_stack_noalloc(void * ptr)346 static inline void kasan_record_aux_stack_noalloc(void *ptr) {}
347
348 #endif /* CONFIG_KASAN_GENERIC */
349
350 #if defined(CONFIG_KASAN_SW_TAGS) || defined(CONFIG_KASAN_HW_TAGS)
351
kasan_reset_tag(const void * addr)352 static inline void *kasan_reset_tag(const void *addr)
353 {
354 return (void *)arch_kasan_reset_tag(addr);
355 }
356
357 /**
358 * kasan_report - print a report about a bad memory access detected by KASAN
359 * @addr: address of the bad access
360 * @size: size of the bad access
361 * @is_write: whether the bad access is a write or a read
362 * @ip: instruction pointer for the accessibility check or the bad access itself
363 */
364 bool kasan_report(unsigned long addr, size_t size,
365 bool is_write, unsigned long ip);
366
367 #else /* CONFIG_KASAN_SW_TAGS || CONFIG_KASAN_HW_TAGS */
368
kasan_reset_tag(const void * addr)369 static inline void *kasan_reset_tag(const void *addr)
370 {
371 return (void *)addr;
372 }
373
374 #endif /* CONFIG_KASAN_SW_TAGS || CONFIG_KASAN_HW_TAGS*/
375
376 #ifdef CONFIG_KASAN_HW_TAGS
377
378 void kasan_report_async(void);
379
380 #endif /* CONFIG_KASAN_HW_TAGS */
381
382 #ifdef CONFIG_KASAN_SW_TAGS
383 void __init kasan_init_sw_tags(void);
384 #else
kasan_init_sw_tags(void)385 static inline void kasan_init_sw_tags(void) { }
386 #endif
387
388 #ifdef CONFIG_KASAN_HW_TAGS
389 void kasan_init_hw_tags_cpu(void);
390 void __init kasan_init_hw_tags(void);
391 #else
kasan_init_hw_tags_cpu(void)392 static inline void kasan_init_hw_tags_cpu(void) { }
kasan_init_hw_tags(void)393 static inline void kasan_init_hw_tags(void) { }
394 #endif
395
396 #ifdef CONFIG_KASAN_VMALLOC
397
398 #if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)
399
400 void kasan_populate_early_vm_area_shadow(void *start, unsigned long size);
401 int kasan_populate_vmalloc(unsigned long addr, unsigned long size);
402 void kasan_release_vmalloc(unsigned long start, unsigned long end,
403 unsigned long free_region_start,
404 unsigned long free_region_end);
405
406 #else /* CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS */
407
kasan_populate_early_vm_area_shadow(void * start,unsigned long size)408 static inline void kasan_populate_early_vm_area_shadow(void *start,
409 unsigned long size)
410 { }
kasan_populate_vmalloc(unsigned long start,unsigned long size)411 static inline int kasan_populate_vmalloc(unsigned long start,
412 unsigned long size)
413 {
414 return 0;
415 }
kasan_release_vmalloc(unsigned long start,unsigned long end,unsigned long free_region_start,unsigned long free_region_end)416 static inline void kasan_release_vmalloc(unsigned long start,
417 unsigned long end,
418 unsigned long free_region_start,
419 unsigned long free_region_end) { }
420
421 #endif /* CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS */
422
423 void *__kasan_unpoison_vmalloc(const void *start, unsigned long size,
424 kasan_vmalloc_flags_t flags);
kasan_unpoison_vmalloc(const void * start,unsigned long size,kasan_vmalloc_flags_t flags)425 static __always_inline void *kasan_unpoison_vmalloc(const void *start,
426 unsigned long size,
427 kasan_vmalloc_flags_t flags)
428 {
429 if (kasan_enabled())
430 return __kasan_unpoison_vmalloc(start, size, flags);
431 return (void *)start;
432 }
433
434 void __kasan_poison_vmalloc(const void *start, unsigned long size);
kasan_poison_vmalloc(const void * start,unsigned long size)435 static __always_inline void kasan_poison_vmalloc(const void *start,
436 unsigned long size)
437 {
438 if (kasan_enabled())
439 __kasan_poison_vmalloc(start, size);
440 }
441
442 #else /* CONFIG_KASAN_VMALLOC */
443
kasan_populate_early_vm_area_shadow(void * start,unsigned long size)444 static inline void kasan_populate_early_vm_area_shadow(void *start,
445 unsigned long size) { }
kasan_populate_vmalloc(unsigned long start,unsigned long size)446 static inline int kasan_populate_vmalloc(unsigned long start,
447 unsigned long size)
448 {
449 return 0;
450 }
kasan_release_vmalloc(unsigned long start,unsigned long end,unsigned long free_region_start,unsigned long free_region_end)451 static inline void kasan_release_vmalloc(unsigned long start,
452 unsigned long end,
453 unsigned long free_region_start,
454 unsigned long free_region_end) { }
455
kasan_unpoison_vmalloc(const void * start,unsigned long size,kasan_vmalloc_flags_t flags)456 static inline void *kasan_unpoison_vmalloc(const void *start,
457 unsigned long size,
458 kasan_vmalloc_flags_t flags)
459 {
460 return (void *)start;
461 }
kasan_poison_vmalloc(const void * start,unsigned long size)462 static inline void kasan_poison_vmalloc(const void *start, unsigned long size)
463 { }
464
465 #endif /* CONFIG_KASAN_VMALLOC */
466
467 #if (defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)) && \
468 !defined(CONFIG_KASAN_VMALLOC)
469
470 /*
471 * These functions allocate and free shadow memory for kernel modules.
472 * They are only required when KASAN_VMALLOC is not supported, as otherwise
473 * shadow memory is allocated by the generic vmalloc handlers.
474 */
475 int kasan_alloc_module_shadow(void *addr, size_t size, gfp_t gfp_mask);
476 void kasan_free_module_shadow(const struct vm_struct *vm);
477
478 #else /* (CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS) && !CONFIG_KASAN_VMALLOC */
479
kasan_alloc_module_shadow(void * addr,size_t size,gfp_t gfp_mask)480 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)481 static inline void kasan_free_module_shadow(const struct vm_struct *vm) {}
482
483 #endif /* (CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS) && !CONFIG_KASAN_VMALLOC */
484
485 #ifdef CONFIG_KASAN_INLINE
486 void kasan_non_canonical_hook(unsigned long addr);
487 #else /* CONFIG_KASAN_INLINE */
kasan_non_canonical_hook(unsigned long addr)488 static inline void kasan_non_canonical_hook(unsigned long addr) { }
489 #endif /* CONFIG_KASAN_INLINE */
490
491 #endif /* LINUX_KASAN_H */
492