xref: /openbmc/linux/mm/kasan/kasan.h (revision 06701297)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef __MM_KASAN_KASAN_H
3 #define __MM_KASAN_KASAN_H
4 
5 #include <linux/kasan.h>
6 #include <linux/stackdepot.h>
7 
8 #ifdef CONFIG_KASAN_HW_TAGS
9 #include <linux/static_key.h>
10 DECLARE_STATIC_KEY_FALSE(kasan_flag_stacktrace);
11 static inline bool kasan_stack_collection_enabled(void)
12 {
13 	return static_branch_unlikely(&kasan_flag_stacktrace);
14 }
15 #else
16 static inline bool kasan_stack_collection_enabled(void)
17 {
18 	return true;
19 }
20 #endif
21 
22 extern bool kasan_flag_panic __ro_after_init;
23 
24 #if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)
25 #define KASAN_GRANULE_SIZE	(1UL << KASAN_SHADOW_SCALE_SHIFT)
26 #else
27 #include <asm/mte-kasan.h>
28 #define KASAN_GRANULE_SIZE	MTE_GRANULE_SIZE
29 #endif
30 
31 #define KASAN_GRANULE_MASK	(KASAN_GRANULE_SIZE - 1)
32 
33 #define KASAN_MEMORY_PER_SHADOW_PAGE	(KASAN_GRANULE_SIZE << PAGE_SHIFT)
34 
35 #define KASAN_TAG_KERNEL	0xFF /* native kernel pointers tag */
36 #define KASAN_TAG_INVALID	0xFE /* inaccessible memory tag */
37 #define KASAN_TAG_MAX		0xFD /* maximum value for random tags */
38 
39 #ifdef CONFIG_KASAN_GENERIC
40 #define KASAN_FREE_PAGE         0xFF  /* page was freed */
41 #define KASAN_PAGE_REDZONE      0xFE  /* redzone for kmalloc_large allocations */
42 #define KASAN_KMALLOC_REDZONE   0xFC  /* redzone inside slub object */
43 #define KASAN_KMALLOC_FREE      0xFB  /* object was freed (kmem_cache_free/kfree) */
44 #define KASAN_KMALLOC_FREETRACK 0xFA  /* object was freed and has free track set */
45 #else
46 #define KASAN_FREE_PAGE         KASAN_TAG_INVALID
47 #define KASAN_PAGE_REDZONE      KASAN_TAG_INVALID
48 #define KASAN_KMALLOC_REDZONE   KASAN_TAG_INVALID
49 #define KASAN_KMALLOC_FREE      KASAN_TAG_INVALID
50 #define KASAN_KMALLOC_FREETRACK KASAN_TAG_INVALID
51 #endif
52 
53 #define KASAN_GLOBAL_REDZONE    0xF9  /* redzone for global variable */
54 #define KASAN_VMALLOC_INVALID   0xF8  /* unallocated space in vmapped page */
55 
56 /*
57  * Stack redzone shadow values
58  * (Those are compiler's ABI, don't change them)
59  */
60 #define KASAN_STACK_LEFT        0xF1
61 #define KASAN_STACK_MID         0xF2
62 #define KASAN_STACK_RIGHT       0xF3
63 #define KASAN_STACK_PARTIAL     0xF4
64 
65 /*
66  * alloca redzone shadow values
67  */
68 #define KASAN_ALLOCA_LEFT	0xCA
69 #define KASAN_ALLOCA_RIGHT	0xCB
70 
71 #define KASAN_ALLOCA_REDZONE_SIZE	32
72 
73 /*
74  * Stack frame marker (compiler ABI).
75  */
76 #define KASAN_CURRENT_STACK_FRAME_MAGIC 0x41B58AB3
77 
78 /* Don't break randconfig/all*config builds */
79 #ifndef KASAN_ABI_VERSION
80 #define KASAN_ABI_VERSION 1
81 #endif
82 
83 /* Metadata layout customization. */
84 #define META_BYTES_PER_BLOCK 1
85 #define META_BLOCKS_PER_ROW 16
86 #define META_BYTES_PER_ROW (META_BLOCKS_PER_ROW * META_BYTES_PER_BLOCK)
87 #define META_MEM_BYTES_PER_ROW (META_BYTES_PER_ROW * KASAN_GRANULE_SIZE)
88 #define META_ROWS_AROUND_ADDR 2
89 
90 struct kasan_access_info {
91 	const void *access_addr;
92 	const void *first_bad_addr;
93 	size_t access_size;
94 	bool is_write;
95 	unsigned long ip;
96 };
97 
98 /* The layout of struct dictated by compiler */
99 struct kasan_source_location {
100 	const char *filename;
101 	int line_no;
102 	int column_no;
103 };
104 
105 /* The layout of struct dictated by compiler */
106 struct kasan_global {
107 	const void *beg;		/* Address of the beginning of the global variable. */
108 	size_t size;			/* Size of the global variable. */
109 	size_t size_with_redzone;	/* Size of the variable + size of the red zone. 32 bytes aligned */
110 	const void *name;
111 	const void *module_name;	/* Name of the module where the global variable is declared. */
112 	unsigned long has_dynamic_init;	/* This needed for C++ */
113 #if KASAN_ABI_VERSION >= 4
114 	struct kasan_source_location *location;
115 #endif
116 #if KASAN_ABI_VERSION >= 5
117 	char *odr_indicator;
118 #endif
119 };
120 
121 /**
122  * Structures to keep alloc and free tracks *
123  */
124 
125 #define KASAN_STACK_DEPTH 64
126 
127 struct kasan_track {
128 	u32 pid;
129 	depot_stack_handle_t stack;
130 };
131 
132 #ifdef CONFIG_KASAN_SW_TAGS_IDENTIFY
133 #define KASAN_NR_FREE_STACKS 5
134 #else
135 #define KASAN_NR_FREE_STACKS 1
136 #endif
137 
138 struct kasan_alloc_meta {
139 	struct kasan_track alloc_track;
140 #ifdef CONFIG_KASAN_GENERIC
141 	/*
142 	 * call_rcu() call stack is stored into struct kasan_alloc_meta.
143 	 * The free stack is stored into struct kasan_free_meta.
144 	 */
145 	depot_stack_handle_t aux_stack[2];
146 #else
147 	struct kasan_track free_track[KASAN_NR_FREE_STACKS];
148 #endif
149 #ifdef CONFIG_KASAN_SW_TAGS_IDENTIFY
150 	u8 free_pointer_tag[KASAN_NR_FREE_STACKS];
151 	u8 free_track_idx;
152 #endif
153 };
154 
155 struct qlist_node {
156 	struct qlist_node *next;
157 };
158 
159 /*
160  * Generic mode either stores free meta in the object itself or in the redzone
161  * after the object. In the former case free meta offset is 0, in the latter
162  * case it has some sane value smaller than INT_MAX. Use INT_MAX as free meta
163  * offset when free meta isn't present.
164  */
165 #define KASAN_NO_FREE_META INT_MAX
166 
167 struct kasan_free_meta {
168 #ifdef CONFIG_KASAN_GENERIC
169 	/* This field is used while the object is in the quarantine.
170 	 * Otherwise it might be used for the allocator freelist.
171 	 */
172 	struct qlist_node quarantine_link;
173 	struct kasan_track free_track;
174 #endif
175 };
176 
177 struct kasan_alloc_meta *kasan_get_alloc_meta(struct kmem_cache *cache,
178 						const void *object);
179 #ifdef CONFIG_KASAN_GENERIC
180 struct kasan_free_meta *kasan_get_free_meta(struct kmem_cache *cache,
181 						const void *object);
182 #endif
183 
184 #if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)
185 
186 static inline const void *kasan_shadow_to_mem(const void *shadow_addr)
187 {
188 	return (void *)(((unsigned long)shadow_addr - KASAN_SHADOW_OFFSET)
189 		<< KASAN_SHADOW_SCALE_SHIFT);
190 }
191 
192 static inline bool addr_has_metadata(const void *addr)
193 {
194 	return (addr >= kasan_shadow_to_mem((void *)KASAN_SHADOW_START));
195 }
196 
197 /**
198  * check_memory_region - Check memory region, and report if invalid access.
199  * @addr: the accessed address
200  * @size: the accessed size
201  * @write: true if access is a write access
202  * @ret_ip: return address
203  * @return: true if access was valid, false if invalid
204  */
205 bool check_memory_region(unsigned long addr, size_t size, bool write,
206 				unsigned long ret_ip);
207 
208 #else /* CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS */
209 
210 static inline bool addr_has_metadata(const void *addr)
211 {
212 	return (is_vmalloc_addr(addr) || virt_addr_valid(addr));
213 }
214 
215 #endif /* CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS */
216 
217 #if defined(CONFIG_KASAN_SW_TAGS) || defined(CONFIG_KASAN_HW_TAGS)
218 void print_tags(u8 addr_tag, const void *addr);
219 #else
220 static inline void print_tags(u8 addr_tag, const void *addr) { }
221 #endif
222 
223 void *find_first_bad_addr(void *addr, size_t size);
224 const char *get_bug_type(struct kasan_access_info *info);
225 void metadata_fetch_row(char *buffer, void *row);
226 
227 #if defined(CONFIG_KASAN_GENERIC) && CONFIG_KASAN_STACK
228 void print_address_stack_frame(const void *addr);
229 #else
230 static inline void print_address_stack_frame(const void *addr) { }
231 #endif
232 
233 bool kasan_report(unsigned long addr, size_t size,
234 		bool is_write, unsigned long ip);
235 void kasan_report_invalid_free(void *object, unsigned long ip);
236 
237 struct page *kasan_addr_to_page(const void *addr);
238 
239 depot_stack_handle_t kasan_save_stack(gfp_t flags);
240 void kasan_set_track(struct kasan_track *track, gfp_t flags);
241 void kasan_set_free_info(struct kmem_cache *cache, void *object, u8 tag);
242 struct kasan_track *kasan_get_free_track(struct kmem_cache *cache,
243 				void *object, u8 tag);
244 
245 #if defined(CONFIG_KASAN_GENERIC) && \
246 	(defined(CONFIG_SLAB) || defined(CONFIG_SLUB))
247 bool quarantine_put(struct kmem_cache *cache, void *object);
248 void quarantine_reduce(void);
249 void quarantine_remove_cache(struct kmem_cache *cache);
250 #else
251 static inline bool quarantine_put(struct kmem_cache *cache, void *object) { return false; }
252 static inline void quarantine_reduce(void) { }
253 static inline void quarantine_remove_cache(struct kmem_cache *cache) { }
254 #endif
255 
256 #ifndef arch_kasan_set_tag
257 static inline const void *arch_kasan_set_tag(const void *addr, u8 tag)
258 {
259 	return addr;
260 }
261 #endif
262 #ifndef arch_kasan_get_tag
263 #define arch_kasan_get_tag(addr)	0
264 #endif
265 
266 #define set_tag(addr, tag)	((void *)arch_kasan_set_tag((addr), (tag)))
267 #define get_tag(addr)		arch_kasan_get_tag(addr)
268 
269 #ifdef CONFIG_KASAN_HW_TAGS
270 
271 #ifndef arch_enable_tagging
272 #define arch_enable_tagging()
273 #endif
274 #ifndef arch_init_tags
275 #define arch_init_tags(max_tag)
276 #endif
277 #ifndef arch_get_random_tag
278 #define arch_get_random_tag()	(0xFF)
279 #endif
280 #ifndef arch_get_mem_tag
281 #define arch_get_mem_tag(addr)	(0xFF)
282 #endif
283 #ifndef arch_set_mem_tag_range
284 #define arch_set_mem_tag_range(addr, size, tag) ((void *)(addr))
285 #endif
286 
287 #define hw_enable_tagging()			arch_enable_tagging()
288 #define hw_init_tags(max_tag)			arch_init_tags(max_tag)
289 #define hw_get_random_tag()			arch_get_random_tag()
290 #define hw_get_mem_tag(addr)			arch_get_mem_tag(addr)
291 #define hw_set_mem_tag_range(addr, size, tag)	arch_set_mem_tag_range((addr), (size), (tag))
292 
293 #endif /* CONFIG_KASAN_HW_TAGS */
294 
295 #ifdef CONFIG_KASAN_SW_TAGS
296 u8 random_tag(void);
297 #elif defined(CONFIG_KASAN_HW_TAGS)
298 static inline u8 random_tag(void) { return hw_get_random_tag(); }
299 #else
300 static inline u8 random_tag(void) { return 0; }
301 #endif
302 
303 #ifdef CONFIG_KASAN_HW_TAGS
304 
305 static inline void poison_range(const void *address, size_t size, u8 value)
306 {
307 	hw_set_mem_tag_range(kasan_reset_tag(address),
308 			round_up(size, KASAN_GRANULE_SIZE), value);
309 }
310 
311 static inline void unpoison_range(const void *address, size_t size)
312 {
313 	hw_set_mem_tag_range(kasan_reset_tag(address),
314 			round_up(size, KASAN_GRANULE_SIZE), get_tag(address));
315 }
316 
317 static inline bool check_invalid_free(void *addr)
318 {
319 	u8 ptr_tag = get_tag(addr);
320 	u8 mem_tag = hw_get_mem_tag(addr);
321 
322 	return (mem_tag == KASAN_TAG_INVALID) ||
323 		(ptr_tag != KASAN_TAG_KERNEL && ptr_tag != mem_tag);
324 }
325 
326 #else /* CONFIG_KASAN_HW_TAGS */
327 
328 void poison_range(const void *address, size_t size, u8 value);
329 void unpoison_range(const void *address, size_t size);
330 bool check_invalid_free(void *addr);
331 
332 #endif /* CONFIG_KASAN_HW_TAGS */
333 
334 /*
335  * Exported functions for interfaces called from assembly or from generated
336  * code. Declarations here to avoid warning about missing declarations.
337  */
338 asmlinkage void kasan_unpoison_task_stack_below(const void *watermark);
339 void __asan_register_globals(struct kasan_global *globals, size_t size);
340 void __asan_unregister_globals(struct kasan_global *globals, size_t size);
341 void __asan_handle_no_return(void);
342 void __asan_alloca_poison(unsigned long addr, size_t size);
343 void __asan_allocas_unpoison(const void *stack_top, const void *stack_bottom);
344 
345 void __asan_load1(unsigned long addr);
346 void __asan_store1(unsigned long addr);
347 void __asan_load2(unsigned long addr);
348 void __asan_store2(unsigned long addr);
349 void __asan_load4(unsigned long addr);
350 void __asan_store4(unsigned long addr);
351 void __asan_load8(unsigned long addr);
352 void __asan_store8(unsigned long addr);
353 void __asan_load16(unsigned long addr);
354 void __asan_store16(unsigned long addr);
355 void __asan_loadN(unsigned long addr, size_t size);
356 void __asan_storeN(unsigned long addr, size_t size);
357 
358 void __asan_load1_noabort(unsigned long addr);
359 void __asan_store1_noabort(unsigned long addr);
360 void __asan_load2_noabort(unsigned long addr);
361 void __asan_store2_noabort(unsigned long addr);
362 void __asan_load4_noabort(unsigned long addr);
363 void __asan_store4_noabort(unsigned long addr);
364 void __asan_load8_noabort(unsigned long addr);
365 void __asan_store8_noabort(unsigned long addr);
366 void __asan_load16_noabort(unsigned long addr);
367 void __asan_store16_noabort(unsigned long addr);
368 void __asan_loadN_noabort(unsigned long addr, size_t size);
369 void __asan_storeN_noabort(unsigned long addr, size_t size);
370 
371 void __asan_report_load1_noabort(unsigned long addr);
372 void __asan_report_store1_noabort(unsigned long addr);
373 void __asan_report_load2_noabort(unsigned long addr);
374 void __asan_report_store2_noabort(unsigned long addr);
375 void __asan_report_load4_noabort(unsigned long addr);
376 void __asan_report_store4_noabort(unsigned long addr);
377 void __asan_report_load8_noabort(unsigned long addr);
378 void __asan_report_store8_noabort(unsigned long addr);
379 void __asan_report_load16_noabort(unsigned long addr);
380 void __asan_report_store16_noabort(unsigned long addr);
381 void __asan_report_load_n_noabort(unsigned long addr, size_t size);
382 void __asan_report_store_n_noabort(unsigned long addr, size_t size);
383 
384 void __asan_set_shadow_00(const void *addr, size_t size);
385 void __asan_set_shadow_f1(const void *addr, size_t size);
386 void __asan_set_shadow_f2(const void *addr, size_t size);
387 void __asan_set_shadow_f3(const void *addr, size_t size);
388 void __asan_set_shadow_f5(const void *addr, size_t size);
389 void __asan_set_shadow_f8(const void *addr, size_t size);
390 
391 void __hwasan_load1_noabort(unsigned long addr);
392 void __hwasan_store1_noabort(unsigned long addr);
393 void __hwasan_load2_noabort(unsigned long addr);
394 void __hwasan_store2_noabort(unsigned long addr);
395 void __hwasan_load4_noabort(unsigned long addr);
396 void __hwasan_store4_noabort(unsigned long addr);
397 void __hwasan_load8_noabort(unsigned long addr);
398 void __hwasan_store8_noabort(unsigned long addr);
399 void __hwasan_load16_noabort(unsigned long addr);
400 void __hwasan_store16_noabort(unsigned long addr);
401 void __hwasan_loadN_noabort(unsigned long addr, size_t size);
402 void __hwasan_storeN_noabort(unsigned long addr, size_t size);
403 
404 void __hwasan_tag_memory(unsigned long addr, u8 tag, unsigned long size);
405 
406 #endif
407