linux-stable/include/linux/kasan.h
Andrey Konovalov 200072ce33 kasan: unify large kfree checks
Unify checks in kasan_kfree_large() and in kasan_slab_free_mempool() for
large allocations as it's done for small kfree() allocations.

With this change, kasan_slab_free_mempool() starts checking that the first
byte of the memory that's being freed is accessible.

Link: https://lkml.kernel.org/r/14ffc4cd867e0b1ed58f7527e3b748a1b4ad08aa.1612546384.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Branislav Rankov <Branislav.Rankov@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Kevin Brodsky <kevin.brodsky@arm.com>
Cc: Peter Collingbourne <pcc@google.com>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-02-26 09:41:03 -08:00

445 lines
12 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _LINUX_KASAN_H
#define _LINUX_KASAN_H
#include <linux/static_key.h>
#include <linux/types.h>
struct kmem_cache;
struct page;
struct vm_struct;
struct task_struct;
#ifdef CONFIG_KASAN
#include <linux/linkage.h>
#include <asm/kasan.h>
/* kasan_data struct is used in KUnit tests for KASAN expected failures */
struct kunit_kasan_expectation {
bool report_expected;
bool report_found;
};
#endif
#if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)
#include <linux/pgtable.h>
/* Software KASAN implementations use shadow memory. */
#ifdef CONFIG_KASAN_SW_TAGS
#define KASAN_SHADOW_INIT 0xFF
#else
#define KASAN_SHADOW_INIT 0
#endif
#ifndef PTE_HWTABLE_PTRS
#define PTE_HWTABLE_PTRS 0
#endif
extern unsigned char kasan_early_shadow_page[PAGE_SIZE];
extern pte_t kasan_early_shadow_pte[PTRS_PER_PTE + PTE_HWTABLE_PTRS];
extern pmd_t kasan_early_shadow_pmd[PTRS_PER_PMD];
extern pud_t kasan_early_shadow_pud[PTRS_PER_PUD];
extern p4d_t kasan_early_shadow_p4d[MAX_PTRS_PER_P4D];
int kasan_populate_early_shadow(const void *shadow_start,
const void *shadow_end);
static inline void *kasan_mem_to_shadow(const void *addr)
{
return (void *)((unsigned long)addr >> KASAN_SHADOW_SCALE_SHIFT)
+ KASAN_SHADOW_OFFSET;
}
int kasan_add_zero_shadow(void *start, unsigned long size);
void kasan_remove_zero_shadow(void *start, unsigned long size);
/* Enable reporting bugs after kasan_disable_current() */
extern void kasan_enable_current(void);
/* Disable reporting bugs for current task */
extern void kasan_disable_current(void);
#else /* CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS */
static inline int kasan_add_zero_shadow(void *start, unsigned long size)
{
return 0;
}
static inline void kasan_remove_zero_shadow(void *start,
unsigned long size)
{}
static inline void kasan_enable_current(void) {}
static inline void kasan_disable_current(void) {}
#endif /* CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS */
#ifdef CONFIG_KASAN
struct kasan_cache {
int alloc_meta_offset;
int free_meta_offset;
bool is_kmalloc;
};
#ifdef CONFIG_KASAN_HW_TAGS
DECLARE_STATIC_KEY_FALSE(kasan_flag_enabled);
static __always_inline bool kasan_enabled(void)
{
return static_branch_likely(&kasan_flag_enabled);
}
#else /* CONFIG_KASAN_HW_TAGS */
static inline bool kasan_enabled(void)
{
return true;
}
#endif /* CONFIG_KASAN_HW_TAGS */
slab_flags_t __kasan_never_merge(void);
static __always_inline slab_flags_t kasan_never_merge(void)
{
if (kasan_enabled())
return __kasan_never_merge();
return 0;
}
void __kasan_unpoison_range(const void *addr, size_t size);
static __always_inline void kasan_unpoison_range(const void *addr, size_t size)
{
if (kasan_enabled())
__kasan_unpoison_range(addr, size);
}
void __kasan_alloc_pages(struct page *page, unsigned int order);
static __always_inline void kasan_alloc_pages(struct page *page,
unsigned int order)
{
if (kasan_enabled())
__kasan_alloc_pages(page, order);
}
void __kasan_free_pages(struct page *page, unsigned int order);
static __always_inline void kasan_free_pages(struct page *page,
unsigned int order)
{
if (kasan_enabled())
__kasan_free_pages(page, order);
}
void __kasan_cache_create(struct kmem_cache *cache, unsigned int *size,
slab_flags_t *flags);
static __always_inline void kasan_cache_create(struct kmem_cache *cache,
unsigned int *size, slab_flags_t *flags)
{
if (kasan_enabled())
__kasan_cache_create(cache, size, flags);
}
void __kasan_cache_create_kmalloc(struct kmem_cache *cache);
static __always_inline void kasan_cache_create_kmalloc(struct kmem_cache *cache)
{
if (kasan_enabled())
__kasan_cache_create_kmalloc(cache);
}
size_t __kasan_metadata_size(struct kmem_cache *cache);
static __always_inline size_t kasan_metadata_size(struct kmem_cache *cache)
{
if (kasan_enabled())
return __kasan_metadata_size(cache);
return 0;
}
void __kasan_poison_slab(struct page *page);
static __always_inline void kasan_poison_slab(struct page *page)
{
if (kasan_enabled())
__kasan_poison_slab(page);
}
void __kasan_unpoison_object_data(struct kmem_cache *cache, void *object);
static __always_inline void kasan_unpoison_object_data(struct kmem_cache *cache,
void *object)
{
if (kasan_enabled())
__kasan_unpoison_object_data(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 *object)
{
if (kasan_enabled())
__kasan_poison_object_data(cache, object);
}
void * __must_check __kasan_init_slab_obj(struct kmem_cache *cache,
const void *object);
static __always_inline void * __must_check kasan_init_slab_obj(
struct kmem_cache *cache, const void *object)
{
if (kasan_enabled())
return __kasan_init_slab_obj(cache, object);
return (void *)object;
}
bool __kasan_slab_free(struct kmem_cache *s, void *object, unsigned long ip);
static __always_inline bool kasan_slab_free(struct kmem_cache *s, void *object)
{
if (kasan_enabled())
return __kasan_slab_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)
{
if (kasan_enabled())
__kasan_kfree_large(ptr, _RET_IP_);
}
void __kasan_slab_free_mempool(void *ptr, unsigned long ip);
static __always_inline void kasan_slab_free_mempool(void *ptr)
{
if (kasan_enabled())
__kasan_slab_free_mempool(ptr, _RET_IP_);
}
void * __must_check __kasan_slab_alloc(struct kmem_cache *s,
void *object, gfp_t flags);
static __always_inline void * __must_check kasan_slab_alloc(
struct kmem_cache *s, void *object, gfp_t flags)
{
if (kasan_enabled())
return __kasan_slab_alloc(s, object, flags);
return object;
}
void * __must_check __kasan_kmalloc(struct kmem_cache *s, const void *object,
size_t size, gfp_t flags);
static __always_inline void * __must_check kasan_kmalloc(struct kmem_cache *s,
const void *object, size_t size, gfp_t flags)
{
if (kasan_enabled())
return __kasan_kmalloc(s, object, size, flags);
return (void *)object;
}
void * __must_check __kasan_kmalloc_large(const void *ptr,
size_t size, gfp_t flags);
static __always_inline void * __must_check kasan_kmalloc_large(const void *ptr,
size_t size, gfp_t flags)
{
if (kasan_enabled())
return __kasan_kmalloc_large(ptr, size, flags);
return (void *)ptr;
}
void * __must_check __kasan_krealloc(const void *object,
size_t new_size, gfp_t flags);
static __always_inline void * __must_check kasan_krealloc(const void *object,
size_t new_size, gfp_t flags)
{
if (kasan_enabled())
return __kasan_krealloc(object, new_size, flags);
return (void *)object;
}
/*
* Unlike kasan_check_read/write(), kasan_check_byte() is performed even for
* the hardware tag-based mode that doesn't rely on compiler instrumentation.
*/
bool __kasan_check_byte(const void *addr, unsigned long ip);
static __always_inline bool kasan_check_byte(const void *addr)
{
if (kasan_enabled())
return __kasan_check_byte(addr, _RET_IP_);
return true;
}
bool kasan_save_enable_multi_shot(void);
void kasan_restore_multi_shot(bool enabled);
#else /* CONFIG_KASAN */
static inline bool kasan_enabled(void)
{
return false;
}
static inline slab_flags_t kasan_never_merge(void)
{
return 0;
}
static inline void kasan_unpoison_range(const void *address, size_t size) {}
static inline void kasan_alloc_pages(struct page *page, unsigned int order) {}
static inline void kasan_free_pages(struct page *page, unsigned int order) {}
static inline void kasan_cache_create(struct kmem_cache *cache,
unsigned int *size,
slab_flags_t *flags) {}
static inline void kasan_cache_create_kmalloc(struct kmem_cache *cache) {}
static inline size_t kasan_metadata_size(struct kmem_cache *cache) { return 0; }
static inline void kasan_poison_slab(struct page *page) {}
static inline void kasan_unpoison_object_data(struct kmem_cache *cache,
void *object) {}
static inline void kasan_poison_object_data(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)
{
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)
{
return object;
}
static inline void *kasan_kmalloc(struct kmem_cache *s, const void *object,
size_t size, gfp_t flags)
{
return (void *)object;
}
static inline void *kasan_kmalloc_large(const void *ptr, size_t size, gfp_t flags)
{
return (void *)ptr;
}
static inline void *kasan_krealloc(const void *object, size_t new_size,
gfp_t flags)
{
return (void *)object;
}
static inline bool kasan_check_byte(const void *address)
{
return true;
}
#endif /* CONFIG_KASAN */
#if defined(CONFIG_KASAN) && CONFIG_KASAN_STACK
void kasan_unpoison_task_stack(struct task_struct *task);
#else
static inline void kasan_unpoison_task_stack(struct task_struct *task) {}
#endif
#ifdef CONFIG_KASAN_GENERIC
void kasan_cache_shrink(struct kmem_cache *cache);
void kasan_cache_shutdown(struct kmem_cache *cache);
void kasan_record_aux_stack(void *ptr);
#else /* CONFIG_KASAN_GENERIC */
static inline void kasan_cache_shrink(struct kmem_cache *cache) {}
static inline void kasan_cache_shutdown(struct kmem_cache *cache) {}
static inline void kasan_record_aux_stack(void *ptr) {}
#endif /* CONFIG_KASAN_GENERIC */
#if defined(CONFIG_KASAN_SW_TAGS) || defined(CONFIG_KASAN_HW_TAGS)
static inline void *kasan_reset_tag(const void *addr)
{
return (void *)arch_kasan_reset_tag(addr);
}
/**
* kasan_report - print a report about a bad memory access detected by KASAN
* @addr: address of the bad access
* @size: size of the bad access
* @is_write: whether the bad access is a write or a read
* @ip: instruction pointer for the accessibility check or the bad access itself
*/
bool kasan_report(unsigned long addr, size_t size,
bool is_write, unsigned long ip);
#else /* CONFIG_KASAN_SW_TAGS || CONFIG_KASAN_HW_TAGS */
static inline void *kasan_reset_tag(const void *addr)
{
return (void *)addr;
}
#endif /* CONFIG_KASAN_SW_TAGS || CONFIG_KASAN_HW_TAGS*/
#ifdef CONFIG_KASAN_SW_TAGS
void __init kasan_init_sw_tags(void);
#else
static inline void kasan_init_sw_tags(void) { }
#endif
#ifdef CONFIG_KASAN_HW_TAGS
void kasan_init_hw_tags_cpu(void);
void __init kasan_init_hw_tags(void);
#else
static inline void kasan_init_hw_tags_cpu(void) { }
static inline void kasan_init_hw_tags(void) { }
#endif
#ifdef CONFIG_KASAN_VMALLOC
int kasan_populate_vmalloc(unsigned long addr, unsigned long size);
void kasan_poison_vmalloc(const void *start, unsigned long size);
void kasan_unpoison_vmalloc(const void *start, unsigned long size);
void kasan_release_vmalloc(unsigned long start, unsigned long end,
unsigned long free_region_start,
unsigned long free_region_end);
#else /* CONFIG_KASAN_VMALLOC */
static inline int kasan_populate_vmalloc(unsigned long start,
unsigned long size)
{
return 0;
}
static inline void kasan_poison_vmalloc(const void *start, unsigned long size)
{ }
static inline void kasan_unpoison_vmalloc(const void *start, unsigned long size)
{ }
static inline void kasan_release_vmalloc(unsigned long start,
unsigned long end,
unsigned long free_region_start,
unsigned long free_region_end) {}
#endif /* CONFIG_KASAN_VMALLOC */
#if (defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)) && \
!defined(CONFIG_KASAN_VMALLOC)
/*
* These functions provide a special case to support backing module
* allocations with real shadow memory. With KASAN vmalloc, the special
* case is unnecessary, as the work is handled in the generic case.
*/
int kasan_module_alloc(void *addr, size_t size);
void kasan_free_shadow(const struct vm_struct *vm);
#else /* (CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS) && !CONFIG_KASAN_VMALLOC */
static inline int kasan_module_alloc(void *addr, size_t size) { return 0; }
static inline void kasan_free_shadow(const struct vm_struct *vm) {}
#endif /* (CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS) && !CONFIG_KASAN_VMALLOC */
#ifdef CONFIG_KASAN_INLINE
void kasan_non_canonical_hook(unsigned long addr);
#else /* CONFIG_KASAN_INLINE */
static inline void kasan_non_canonical_hook(unsigned long addr) { }
#endif /* CONFIG_KASAN_INLINE */
#endif /* LINUX_KASAN_H */