diff options
Diffstat (limited to 'include/linux/kasan.h')
| -rw-r--r-- | include/linux/kasan.h | 245 |
1 files changed, 215 insertions, 30 deletions
diff --git a/include/linux/kasan.h b/include/linux/kasan.h index 71fa9a40fb5a..6bbfc8aa42e8 100644 --- a/include/linux/kasan.h +++ b/include/linux/kasan.h @@ -4,6 +4,7 @@ #include <linux/bug.h> #include <linux/kasan-enabled.h> +#include <linux/kasan-tags.h> #include <linux/kernel.h> #include <linux/static_key.h> #include <linux/types.h> @@ -28,6 +29,9 @@ typedef unsigned int __bitwise kasan_vmalloc_flags_t; #define KASAN_VMALLOC_VM_ALLOC ((__force kasan_vmalloc_flags_t)0x02u) #define KASAN_VMALLOC_PROT_NORMAL ((__force kasan_vmalloc_flags_t)0x04u) +#define KASAN_VMALLOC_PAGE_RANGE 0x1 /* Apply exsiting page range */ +#define KASAN_VMALLOC_TLB_FLUSH 0x2 /* TLB flush */ + #if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS) #include <linux/pgtable.h> @@ -129,20 +133,39 @@ static __always_inline void kasan_poison_slab(struct slab *slab) __kasan_poison_slab(slab); } -void __kasan_unpoison_object_data(struct kmem_cache *cache, void *object); -static __always_inline void kasan_unpoison_object_data(struct kmem_cache *cache, +void __kasan_unpoison_new_object(struct kmem_cache *cache, void *object); +/** + * kasan_unpoison_new_object - Temporarily unpoison a new slab object. + * @cache: Cache the object belong to. + * @object: Pointer to the object. + * + * This function is intended for the slab allocator's internal use. It + * temporarily unpoisons an object from a newly allocated slab without doing + * anything else. The object must later be repoisoned by + * kasan_poison_new_object(). + */ +static __always_inline void kasan_unpoison_new_object(struct kmem_cache *cache, void *object) { if (kasan_enabled()) - __kasan_unpoison_object_data(cache, object); + __kasan_unpoison_new_object(cache, object); } -void __kasan_poison_object_data(struct kmem_cache *cache, void *object); -static __always_inline void kasan_poison_object_data(struct kmem_cache *cache, +void __kasan_poison_new_object(struct kmem_cache *cache, void *object); +/** + * kasan_unpoison_new_object - Repoison a new slab object. + * @cache: Cache the object belong to. + * @object: Pointer to the object. + * + * This function is intended for the slab allocator's internal use. It + * repoisons an object that was previously unpoisoned by + * kasan_unpoison_new_object() without doing anything else. + */ +static __always_inline void kasan_poison_new_object(struct kmem_cache *cache, void *object) { if (kasan_enabled()) - __kasan_poison_object_data(cache, object); + __kasan_poison_new_object(cache, object); } void * __must_check __kasan_init_slab_obj(struct kmem_cache *cache, @@ -155,28 +178,67 @@ static __always_inline void * __must_check kasan_init_slab_obj( return (void *)object; } -bool __kasan_slab_free(struct kmem_cache *s, void *object, - unsigned long ip, bool init); -static __always_inline bool kasan_slab_free(struct kmem_cache *s, - void *object, bool init) +bool __kasan_slab_pre_free(struct kmem_cache *s, void *object, + unsigned long ip); +/** + * kasan_slab_pre_free - Check whether freeing a slab object is safe. + * @object: Object to be freed. + * + * This function checks whether freeing the given object is safe. It may + * check for double-free and invalid-free bugs and report them. + * + * This function is intended only for use by the slab allocator. + * + * @Return true if freeing the object is unsafe; false otherwise. + */ +static __always_inline bool kasan_slab_pre_free(struct kmem_cache *s, + void *object) { if (kasan_enabled()) - return __kasan_slab_free(s, object, _RET_IP_, init); + return __kasan_slab_pre_free(s, object, _RET_IP_); return false; } -void __kasan_kfree_large(void *ptr, unsigned long ip); -static __always_inline void kasan_kfree_large(void *ptr) +bool __kasan_slab_free(struct kmem_cache *s, void *object, bool init, + bool still_accessible); +/** + * kasan_slab_free - Poison, initialize, and quarantine a slab object. + * @object: Object to be freed. + * @init: Whether to initialize the object. + * @still_accessible: Whether the object contents are still accessible. + * + * This function informs that a slab object has been freed and is not + * supposed to be accessed anymore, except when @still_accessible is set + * (indicating that the object is in a SLAB_TYPESAFE_BY_RCU cache and an RCU + * grace period might not have passed yet). + * + * For KASAN modes that have integrated memory initialization + * (kasan_has_integrated_init() == true), this function also initializes + * the object's memory. For other modes, the @init argument is ignored. + * + * This function might also take ownership of the object to quarantine it. + * When this happens, KASAN will defer freeing the object to a later + * stage and handle it internally until then. The return value indicates + * whether KASAN took ownership of the object. + * + * This function is intended only for use by the slab allocator. + * + * @Return true if KASAN took ownership of the object; false otherwise. + */ +static __always_inline bool kasan_slab_free(struct kmem_cache *s, + void *object, bool init, + bool still_accessible) { if (kasan_enabled()) - __kasan_kfree_large(ptr, _RET_IP_); + return __kasan_slab_free(s, object, init, still_accessible); + return false; } -void __kasan_slab_free_mempool(void *ptr, unsigned long ip); -static __always_inline void kasan_slab_free_mempool(void *ptr) +void __kasan_kfree_large(void *ptr, unsigned long ip); +static __always_inline void kasan_kfree_large(void *ptr) { if (kasan_enabled()) - __kasan_slab_free_mempool(ptr, _RET_IP_); + __kasan_kfree_large(ptr, _RET_IP_); } void * __must_check __kasan_slab_alloc(struct kmem_cache *s, @@ -219,6 +281,113 @@ static __always_inline void * __must_check kasan_krealloc(const void *object, return (void *)object; } +bool __kasan_mempool_poison_pages(struct page *page, unsigned int order, + unsigned long ip); +/** + * kasan_mempool_poison_pages - Check and poison a mempool page allocation. + * @page: Pointer to the page allocation. + * @order: Order of the allocation. + * + * This function is intended for kernel subsystems that cache page allocations + * to reuse them instead of freeing them back to page_alloc (e.g. mempool). + * + * This function is similar to kasan_mempool_poison_object() but operates on + * page allocations. + * + * Before the poisoned allocation can be reused, it must be unpoisoned via + * kasan_mempool_unpoison_pages(). + * + * Return: true if the allocation can be safely reused; false otherwise. + */ +static __always_inline bool kasan_mempool_poison_pages(struct page *page, + unsigned int order) +{ + if (kasan_enabled()) + return __kasan_mempool_poison_pages(page, order, _RET_IP_); + return true; +} + +void __kasan_mempool_unpoison_pages(struct page *page, unsigned int order, + unsigned long ip); +/** + * kasan_mempool_unpoison_pages - Unpoison a mempool page allocation. + * @page: Pointer to the page allocation. + * @order: Order of the allocation. + * + * This function is intended for kernel subsystems that cache page allocations + * to reuse them instead of freeing them back to page_alloc (e.g. mempool). + * + * This function unpoisons a page allocation that was previously poisoned by + * kasan_mempool_poison_pages() without zeroing the allocation's memory. For + * the tag-based modes, this function assigns a new tag to the allocation. + */ +static __always_inline void kasan_mempool_unpoison_pages(struct page *page, + unsigned int order) +{ + if (kasan_enabled()) + __kasan_mempool_unpoison_pages(page, order, _RET_IP_); +} + +bool __kasan_mempool_poison_object(void *ptr, unsigned long ip); +/** + * kasan_mempool_poison_object - Check and poison a mempool slab allocation. + * @ptr: Pointer to the slab allocation. + * + * This function is intended for kernel subsystems that cache slab allocations + * to reuse them instead of freeing them back to the slab allocator (e.g. + * mempool). + * + * This function poisons a slab allocation and saves a free stack trace for it + * without initializing the allocation's memory and without putting it into the + * quarantine (for the Generic mode). + * + * This function also performs checks to detect double-free and invalid-free + * bugs and reports them. The caller can use the return value of this function + * to find out if the allocation is buggy. + * + * Before the poisoned allocation can be reused, it must be unpoisoned via + * kasan_mempool_unpoison_object(). + * + * This function operates on all slab allocations including large kmalloc + * allocations (the ones returned by kmalloc_large() or by kmalloc() with the + * size > KMALLOC_MAX_SIZE). + * + * Return: true if the allocation can be safely reused; false otherwise. + */ +static __always_inline bool kasan_mempool_poison_object(void *ptr) +{ + if (kasan_enabled()) + return __kasan_mempool_poison_object(ptr, _RET_IP_); + return true; +} + +void __kasan_mempool_unpoison_object(void *ptr, size_t size, unsigned long ip); +/** + * kasan_mempool_unpoison_object - Unpoison a mempool slab allocation. + * @ptr: Pointer to the slab allocation. + * @size: Size to be unpoisoned. + * + * This function is intended for kernel subsystems that cache slab allocations + * to reuse them instead of freeing them back to the slab allocator (e.g. + * mempool). + * + * This function unpoisons a slab allocation that was previously poisoned via + * kasan_mempool_poison_object() and saves an alloc stack trace for it without + * initializing the allocation's memory. For the tag-based modes, this function + * does not assign a new tag to the allocation and instead restores the + * original tags based on the pointer value. + * + * This function operates on all slab allocations including large kmalloc + * allocations (the ones returned by kmalloc_large() or by kmalloc() with the + * size > KMALLOC_MAX_SIZE). + */ +static __always_inline void kasan_mempool_unpoison_object(void *ptr, + size_t size) +{ + if (kasan_enabled()) + __kasan_mempool_unpoison_object(ptr, size, _RET_IP_); +} + /* * Unlike kasan_check_read/write(), kasan_check_byte() is performed even for * the hardware tag-based mode that doesn't rely on compiler instrumentation. @@ -242,21 +411,27 @@ static inline bool kasan_unpoison_pages(struct page *page, unsigned int order, return false; } static inline void kasan_poison_slab(struct slab *slab) {} -static inline void kasan_unpoison_object_data(struct kmem_cache *cache, +static inline void kasan_unpoison_new_object(struct kmem_cache *cache, void *object) {} -static inline void kasan_poison_object_data(struct kmem_cache *cache, +static inline void kasan_poison_new_object(struct kmem_cache *cache, void *object) {} static inline void *kasan_init_slab_obj(struct kmem_cache *cache, const void *object) { return (void *)object; } -static inline bool kasan_slab_free(struct kmem_cache *s, void *object, bool init) + +static inline bool kasan_slab_pre_free(struct kmem_cache *s, void *object) +{ + return false; +} + +static inline bool kasan_slab_free(struct kmem_cache *s, void *object, + bool init, bool still_accessible) { return false; } static inline void kasan_kfree_large(void *ptr) {} -static inline void kasan_slab_free_mempool(void *ptr) {} static inline void *kasan_slab_alloc(struct kmem_cache *s, void *object, gfp_t flags, bool init) { @@ -276,6 +451,17 @@ static inline void *kasan_krealloc(const void *object, size_t new_size, { return (void *)object; } +static inline bool kasan_mempool_poison_pages(struct page *page, unsigned int order) +{ + return true; +} +static inline void kasan_mempool_unpoison_pages(struct page *page, unsigned int order) {} +static inline bool kasan_mempool_poison_object(void *ptr) +{ + return true; +} +static inline void kasan_mempool_unpoison_object(void *ptr, size_t size) {} + static inline bool kasan_check_byte(const void *address) { return true; @@ -285,8 +471,10 @@ static inline bool kasan_check_byte(const void *address) #if defined(CONFIG_KASAN) && defined(CONFIG_KASAN_STACK) void kasan_unpoison_task_stack(struct task_struct *task); +asmlinkage void kasan_unpoison_task_stack_below(const void *watermark); #else static inline void kasan_unpoison_task_stack(struct task_struct *task) {} +static inline void kasan_unpoison_task_stack_below(const void *watermark) {} #endif #ifdef CONFIG_KASAN_GENERIC @@ -297,7 +485,6 @@ struct kasan_cache { }; size_t kasan_metadata_size(struct kmem_cache *cache, bool in_object); -slab_flags_t kasan_never_merge(void); void kasan_cache_create(struct kmem_cache *cache, unsigned int *size, slab_flags_t *flags); @@ -314,11 +501,6 @@ static inline size_t kasan_metadata_size(struct kmem_cache *cache, { return 0; } -/* And thus nothing prevents cache merging. */ -static inline slab_flags_t kasan_never_merge(void) -{ - return 0; -} /* And no cache-related metadata initialization is required. */ static inline void kasan_cache_create(struct kmem_cache *cache, unsigned int *size, @@ -385,7 +567,8 @@ void kasan_populate_early_vm_area_shadow(void *start, unsigned long size); int kasan_populate_vmalloc(unsigned long addr, unsigned long size); void kasan_release_vmalloc(unsigned long start, unsigned long end, unsigned long free_region_start, - unsigned long free_region_end); + unsigned long free_region_end, + unsigned long flags); #else /* CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS */ @@ -400,7 +583,8 @@ static inline int kasan_populate_vmalloc(unsigned long start, static inline void kasan_release_vmalloc(unsigned long start, unsigned long end, unsigned long free_region_start, - unsigned long free_region_end) { } + unsigned long free_region_end, + unsigned long flags) { } #endif /* CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS */ @@ -435,7 +619,8 @@ static inline int kasan_populate_vmalloc(unsigned long start, static inline void kasan_release_vmalloc(unsigned long start, unsigned long end, unsigned long free_region_start, - unsigned long free_region_end) { } + unsigned long free_region_end, + unsigned long flags) { } static inline void *kasan_unpoison_vmalloc(const void *start, unsigned long size, |