xref: /openbmc/linux/include/linux/kasan.h (revision 78beef62)
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 int kasan_module_alloc(void *addr, size_t size);
74 void kasan_free_shadow(const struct vm_struct *vm);
75 
76 int kasan_add_zero_shadow(void *start, unsigned long size);
77 void kasan_remove_zero_shadow(void *start, unsigned long size);
78 
79 size_t __ksize(const void *);
80 static inline void kasan_unpoison_slab(const void *ptr)
81 {
82 	kasan_unpoison_shadow(ptr, __ksize(ptr));
83 }
84 size_t kasan_metadata_size(struct kmem_cache *cache);
85 
86 bool kasan_save_enable_multi_shot(void);
87 void kasan_restore_multi_shot(bool enabled);
88 
89 #else /* CONFIG_KASAN */
90 
91 static inline void kasan_unpoison_shadow(const void *address, size_t size) {}
92 
93 static inline void kasan_unpoison_task_stack(struct task_struct *task) {}
94 static inline void kasan_unpoison_stack_above_sp_to(const void *watermark) {}
95 
96 static inline void kasan_enable_current(void) {}
97 static inline void kasan_disable_current(void) {}
98 
99 static inline void kasan_alloc_pages(struct page *page, unsigned int order) {}
100 static inline void kasan_free_pages(struct page *page, unsigned int order) {}
101 
102 static inline void kasan_cache_create(struct kmem_cache *cache,
103 				      unsigned int *size,
104 				      slab_flags_t *flags) {}
105 
106 static inline void kasan_poison_slab(struct page *page) {}
107 static inline void kasan_unpoison_object_data(struct kmem_cache *cache,
108 					void *object) {}
109 static inline void kasan_poison_object_data(struct kmem_cache *cache,
110 					void *object) {}
111 static inline void *kasan_init_slab_obj(struct kmem_cache *cache,
112 				const void *object)
113 {
114 	return (void *)object;
115 }
116 
117 static inline void *kasan_kmalloc_large(void *ptr, size_t size, gfp_t flags)
118 {
119 	return ptr;
120 }
121 static inline void kasan_kfree_large(void *ptr, unsigned long ip) {}
122 static inline void kasan_poison_kfree(void *ptr, unsigned long ip) {}
123 static inline void *kasan_kmalloc(struct kmem_cache *s, const void *object,
124 				size_t size, gfp_t flags)
125 {
126 	return (void *)object;
127 }
128 static inline void *kasan_krealloc(const void *object, size_t new_size,
129 				 gfp_t flags)
130 {
131 	return (void *)object;
132 }
133 
134 static inline void *kasan_slab_alloc(struct kmem_cache *s, void *object,
135 				   gfp_t flags)
136 {
137 	return object;
138 }
139 static inline bool kasan_slab_free(struct kmem_cache *s, void *object,
140 				   unsigned long ip)
141 {
142 	return false;
143 }
144 
145 static inline int kasan_module_alloc(void *addr, size_t size) { return 0; }
146 static inline void kasan_free_shadow(const struct vm_struct *vm) {}
147 
148 static inline int kasan_add_zero_shadow(void *start, unsigned long size)
149 {
150 	return 0;
151 }
152 static inline void kasan_remove_zero_shadow(void *start,
153 					unsigned long size)
154 {}
155 
156 static inline void kasan_unpoison_slab(const void *ptr) { }
157 static inline size_t kasan_metadata_size(struct kmem_cache *cache) { return 0; }
158 
159 #endif /* CONFIG_KASAN */
160 
161 #ifdef CONFIG_KASAN_GENERIC
162 
163 #define KASAN_SHADOW_INIT 0
164 
165 void kasan_cache_shrink(struct kmem_cache *cache);
166 void kasan_cache_shutdown(struct kmem_cache *cache);
167 
168 #else /* CONFIG_KASAN_GENERIC */
169 
170 static inline void kasan_cache_shrink(struct kmem_cache *cache) {}
171 static inline void kasan_cache_shutdown(struct kmem_cache *cache) {}
172 
173 #endif /* CONFIG_KASAN_GENERIC */
174 
175 #ifdef CONFIG_KASAN_SW_TAGS
176 
177 #define KASAN_SHADOW_INIT 0xFF
178 
179 void kasan_init_tags(void);
180 
181 void *kasan_reset_tag(const void *addr);
182 
183 void kasan_report(unsigned long addr, size_t size,
184 		bool is_write, unsigned long ip);
185 
186 #else /* CONFIG_KASAN_SW_TAGS */
187 
188 static inline void kasan_init_tags(void) { }
189 
190 static inline void *kasan_reset_tag(const void *addr)
191 {
192 	return (void *)addr;
193 }
194 
195 #endif /* CONFIG_KASAN_SW_TAGS */
196 
197 #endif /* LINUX_KASAN_H */
198