Commit ccb67deb authored by Andrey Konovalov's avatar Andrey Konovalov Committed by Vincenzo Frascino
Browse files

kasan, mm: check kasan_enabled in annotations



Declare the kasan_enabled static key in include/linux/kasan.h and in
include/linux/mm.h and check it in all kasan annotations. This allows to
avoid any slowdown caused by function calls when kasan_enabled is
disabled.

Signed-off-by: default avatarAndrey Konovalov <andreyknvl@google.com>
Link: https://linux-review.googlesource.com/id/I2589451d3c96c97abbcbf714baabe6161c6f153e
parent 45feb525
......@@ -2,6 +2,7 @@
#ifndef _LINUX_KASAN_H
#define _LINUX_KASAN_H
#include <linux/jump_label.h>
#include <linux/types.h>
struct kmem_cache;
......@@ -72,56 +73,179 @@ static inline void kasan_disable_current(void) {}
#ifdef CONFIG_KASAN
void kasan_alloc_pages(struct page *page, unsigned int order);
void kasan_free_pages(struct page *page, unsigned int order);
struct kasan_cache {
int alloc_meta_offset;
int free_meta_offset;
};
void kasan_cache_create(struct kmem_cache *cache, unsigned int *size,
slab_flags_t *flags);
#ifdef CONFIG_KASAN_HW_TAGS
DECLARE_STATIC_KEY_FALSE(kasan_flag_enabled);
static inline kasan_enabled(void)
{
return static_branch_likely(&kasan_flag_enabled);
}
#else
static inline kasan_enabled(void)
{
return true;
}
#endif
void kasan_unpoison_data(const void *address, size_t size);
void kasan_unpoison_slab(const void *ptr);
void __kasan_alloc_pages(struct page *page, unsigned int order);
static inline void kasan_alloc_pages(struct page *page, unsigned int order)
{
if (kasan_enabled())
__kasan_alloc_pages(page, order);
}
void kasan_poison_slab(struct page *page);
void kasan_unpoison_object_data(struct kmem_cache *cache, void *object);
void kasan_poison_object_data(struct kmem_cache *cache, void *object);
void * __must_check kasan_init_slab_obj(struct kmem_cache *cache,
const void *object);
void __kasan_free_pages(struct page *page, unsigned int order);
static inline void kasan_free_pages(struct page *page, unsigned int order)
{
if (kasan_enabled())
__kasan_free_pages(page, order);
}
void * __must_check kasan_kmalloc_large(const void *ptr, size_t size,
gfp_t flags);
void kasan_kfree_large(void *ptr, unsigned long ip);
void kasan_poison_kfree(void *ptr, unsigned long ip);
void * __must_check kasan_kmalloc(struct kmem_cache *s, const void *object,
size_t size, gfp_t flags);
void * __must_check kasan_krealloc(const void *object, size_t new_size,
gfp_t flags);
void __kasan_cache_create(struct kmem_cache *cache, unsigned int *size,
slab_flags_t *flags);
static 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 * __must_check kasan_slab_alloc(struct kmem_cache *s, void *object,
gfp_t flags);
bool kasan_slab_free(struct kmem_cache *s, void *object, unsigned long ip);
size_t __kasan_metadata_size(struct kmem_cache *cache);
static inline size_t kasan_metadata_size(struct kmem_cache *cache)
{
if (kasan_enabled())
return __kasan_metadata_size(cache);
return 0;
}
struct kasan_cache {
int alloc_meta_offset;
int free_meta_offset;
};
void __kasan_unpoison_data(const void *addr, size_t size);
static inline void kasan_unpoison_data(const void *addr, size_t size)
{
if (kasan_enabled())
__kasan_unpoison_data(addr, size);
}
void __kasan_unpoison_slab(const void *ptr);
static inline void kasan_unpoison_slab(const void *ptr)
{
if (kasan_enabled())
__kasan_unpoison_slab(ptr);
}
void __kasan_poison_slab(struct page *page);
static inline void kasan_poison_slab(struct page *page)
{
if (kasan_enabled())
return __kasan_poison_slab(page);
}
void __kasan_unpoison_object_data(struct kmem_cache *cache, void *object);
static inline void kasan_unpoison_object_data(struct kmem_cache *cache, void *object)
{
if (kasan_enabled())
return __kasan_unpoison_object_data(cache, object);
}
void __kasan_poison_object_data(struct kmem_cache *cache, void *object);
static 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 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 inline bool kasan_slab_free(struct kmem_cache *s, void *object, unsigned long ip)
{
if (kasan_enabled())
return __kasan_slab_free(s, object, ip);
return false;
}
void * __must_check __kasan_slab_alloc(struct kmem_cache *s,
void *object, gfp_t flags);
static 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;
}
size_t kasan_metadata_size(struct kmem_cache *cache);
void * __must_check __kasan_kmalloc(struct kmem_cache *s, const void *object,
size_t size, gfp_t flags);
static 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 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 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;
}
void __kasan_poison_kfree(void *ptr, unsigned long ip);
static inline void kasan_poison_kfree(void *ptr, unsigned long ip)
{
if (kasan_enabled())
__kasan_poison_kfree(ptr, ip);
}
void __kasan_kfree_large(void *ptr, unsigned long ip);
static inline void kasan_kfree_large(void *ptr, unsigned long ip)
{
if (kasan_enabled())
__kasan_kfree_large(ptr, ip);
}
bool kasan_save_enable_multi_shot(void);
void kasan_restore_multi_shot(bool enabled);
#else /* CONFIG_KASAN */
static inline kasan_enabled(void)
{
return false;
}
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_unpoison_data(const void *address, size_t size) { }
static inline void kasan_unpoison_slab(const void *ptr) { }
static inline size_t kasan_metadata_size(struct kmem_cache *cache) { return 0; }
static inline void kasan_unpoison_data(const void *address, size_t size) {}
static inline void kasan_unpoison_slab(const void *ptr) {}
static inline void kasan_poison_slab(struct page *page) {}
static inline void kasan_unpoison_object_data(struct kmem_cache *cache,
void *object) {}
......@@ -132,36 +256,32 @@ static inline void *kasan_init_slab_obj(struct kmem_cache *cache,
{
return (void *)object;
}
static inline void *kasan_kmalloc_large(void *ptr, size_t size, gfp_t flags)
static inline bool kasan_slab_free(struct kmem_cache *s, void *object,
unsigned long ip)
{
return ptr;
return false;
}
static inline void *kasan_slab_alloc(struct kmem_cache *s, void *object,
gfp_t flags)
{
return object;
}
static inline void kasan_kfree_large(void *ptr, unsigned long ip) {}
static inline void kasan_poison_kfree(void *ptr, unsigned long ip) {}
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 void *kasan_slab_alloc(struct kmem_cache *s, void *object,
gfp_t flags)
{
return object;
}
static inline bool kasan_slab_free(struct kmem_cache *s, void *object,
unsigned long ip)
{
return false;
}
static inline size_t kasan_metadata_size(struct kmem_cache *cache) { return 0; }
static inline void kasan_poison_kfree(void *ptr, unsigned long ip) {}
static inline void kasan_kfree_large(void *ptr, unsigned long ip) {}
#endif /* CONFIG_KASAN */
......
......@@ -31,6 +31,7 @@
#include <linux/sizes.h>
#include <linux/sched.h>
#include <linux/pgtable.h>
#include <linux/kasan.h>
struct mempolicy;
struct anon_vma;
......@@ -1414,22 +1415,30 @@ static inline bool cpupid_match_pid(struct task_struct *task, int cpupid)
#endif /* CONFIG_NUMA_BALANCING */
#if defined(CONFIG_KASAN_SW_TAGS) || defined(CONFIG_KASAN_HW_TAGS)
static inline u8 page_kasan_tag(const struct page *page)
{
return (page->flags >> KASAN_TAG_PGSHIFT) & KASAN_TAG_MASK;
if (kasan_enabled())
return (page->flags >> KASAN_TAG_PGSHIFT) & KASAN_TAG_MASK;
return 0xff;
}
static inline void page_kasan_tag_set(struct page *page, u8 tag)
{
page->flags &= ~(KASAN_TAG_MASK << KASAN_TAG_PGSHIFT);
page->flags |= (tag & KASAN_TAG_MASK) << KASAN_TAG_PGSHIFT;
if (kasan_enabled()) {
page->flags &= ~(KASAN_TAG_MASK << KASAN_TAG_PGSHIFT);
page->flags |= (tag & KASAN_TAG_MASK) << KASAN_TAG_PGSHIFT;
}
}
static inline void page_kasan_tag_reset(struct page *page)
{
page_kasan_tag_set(page, 0xff);
if (kasan_enabled())
page_kasan_tag_set(page, 0xff);
}
#else
#else /* CONFIG_KASAN_SW_TAGS || CONFIG_KASAN_HW_TAGS */
static inline u8 page_kasan_tag(const struct page *page)
{
return 0xff;
......@@ -1437,7 +1446,8 @@ static inline u8 page_kasan_tag(const struct page *page)
static inline void page_kasan_tag_set(struct page *page, u8 tag) { }
static inline void page_kasan_tag_reset(struct page *page) { }
#endif
#endif /* CONFIG_KASAN_SW_TAGS || CONFIG_KASAN_HW_TAGS */
static inline struct zone *page_zone(const struct page *page)
{
......
......@@ -81,7 +81,7 @@ asmlinkage void kasan_unpoison_task_stack_below(const void *watermark)
}
#endif /* CONFIG_KASAN_STACK */
void kasan_alloc_pages(struct page *page, unsigned int order)
void __kasan_alloc_pages(struct page *page, unsigned int order)
{
u8 tag;
unsigned long i;
......@@ -95,7 +95,7 @@ void kasan_alloc_pages(struct page *page, unsigned int order)
kasan_unpoison_memory(page_address(page), PAGE_SIZE << order);
}
void kasan_free_pages(struct page *page, unsigned int order)
void __kasan_free_pages(struct page *page, unsigned int order)
{
if (likely(!PageHighMem(page)))
kasan_poison_memory(page_address(page),
......@@ -122,8 +122,8 @@ static inline unsigned int optimal_redzone(unsigned int object_size)
object_size <= (1 << 16) - 1024 ? 1024 : 2048;
}
void kasan_cache_create(struct kmem_cache *cache, unsigned int *size,
slab_flags_t *flags)
void __kasan_cache_create(struct kmem_cache *cache, unsigned int *size,
slab_flags_t *flags)
{
unsigned int orig_size = *size;
unsigned int redzone_size;
......@@ -168,7 +168,7 @@ void kasan_cache_create(struct kmem_cache *cache, unsigned int *size,
*flags |= SLAB_KASAN;
}
size_t kasan_metadata_size(struct kmem_cache *cache)
size_t __kasan_metadata_size(struct kmem_cache *cache)
{
if (!kasan_stack_collection_enabled())
return 0;
......@@ -191,17 +191,17 @@ struct kasan_free_meta *kasan_get_free_meta(struct kmem_cache *cache,
return kasan_reset_tag(object) + cache->kasan_info.free_meta_offset;
}
void kasan_unpoison_data(const void *address, size_t size)
void __kasan_unpoison_data(const void *addr, size_t size)
{
kasan_unpoison_memory(address, size);
kasan_unpoison_memory(addr, size);
}
void kasan_unpoison_slab(const void *ptr)
void __kasan_unpoison_slab(const void *ptr)
{
kasan_unpoison_memory(ptr, __ksize(ptr));
}
void kasan_poison_slab(struct page *page)
void __kasan_poison_slab(struct page *page)
{
unsigned long i;
......@@ -211,12 +211,12 @@ void kasan_poison_slab(struct page *page)
KASAN_KMALLOC_REDZONE);
}
void kasan_unpoison_object_data(struct kmem_cache *cache, void *object)
void __kasan_unpoison_object_data(struct kmem_cache *cache, void *object)
{
kasan_unpoison_memory(object, cache->object_size);
}
void kasan_poison_object_data(struct kmem_cache *cache, void *object)
void __kasan_poison_object_data(struct kmem_cache *cache, void *object)
{
kasan_poison_memory(object,
round_up(cache->object_size, KASAN_GRANULE_SIZE),
......@@ -269,7 +269,7 @@ static u8 assign_tag(struct kmem_cache *cache, const void *object,
#endif
}
void * __must_check kasan_init_slab_obj(struct kmem_cache *cache,
void * __must_check __kasan_init_slab_obj(struct kmem_cache *cache,
const void *object)
{
struct kasan_alloc_meta *alloc_meta;
......@@ -288,7 +288,7 @@ void * __must_check kasan_init_slab_obj(struct kmem_cache *cache,
return (void *)object;
}
static bool __kasan_slab_free(struct kmem_cache *cache, void *object,
static bool ____kasan_slab_free(struct kmem_cache *cache, void *object,
unsigned long ip, bool quarantine)
{
u8 tag;
......@@ -331,9 +331,9 @@ static bool __kasan_slab_free(struct kmem_cache *cache, void *object,
return IS_ENABLED(CONFIG_KASAN_GENERIC);
}
bool kasan_slab_free(struct kmem_cache *cache, void *object, unsigned long ip)
bool __kasan_slab_free(struct kmem_cache *cache, void *object, unsigned long ip)
{
return __kasan_slab_free(cache, object, ip, true);
return ____kasan_slab_free(cache, object, ip, true);
}
static void set_alloc_info(struct kmem_cache *cache, void *object, gfp_t flags)
......@@ -341,7 +341,7 @@ static void set_alloc_info(struct kmem_cache *cache, void *object, gfp_t flags)
kasan_set_track(&kasan_get_alloc_meta(cache, object)->alloc_track, flags);
}
static void *__kasan_kmalloc(struct kmem_cache *cache, const void *object,
static void *____kasan_kmalloc(struct kmem_cache *cache, const void *object,
size_t size, gfp_t flags, bool keep_tag)
{
unsigned long redzone_start;
......@@ -373,20 +373,20 @@ static void *__kasan_kmalloc(struct kmem_cache *cache, const void *object,
return set_tag(object, tag);
}
void * __must_check kasan_slab_alloc(struct kmem_cache *cache, void *object,
gfp_t flags)
void * __must_check __kasan_slab_alloc(struct kmem_cache *cache,
void *object, gfp_t flags)
{
return __kasan_kmalloc(cache, object, cache->object_size, flags, false);
return ____kasan_kmalloc(cache, object, cache->object_size, flags, false);
}
void * __must_check kasan_kmalloc(struct kmem_cache *cache, const void *object,
size_t size, gfp_t flags)
void * __must_check __kasan_kmalloc(struct kmem_cache *cache, const void *object,
size_t size, gfp_t flags)
{
return __kasan_kmalloc(cache, object, size, flags, true);
return ____kasan_kmalloc(cache, object, size, flags, true);
}
EXPORT_SYMBOL(kasan_kmalloc);
EXPORT_SYMBOL(__kasan_kmalloc);
void * __must_check kasan_kmalloc_large(const void *ptr, size_t size,
void * __must_check __kasan_kmalloc_large(const void *ptr, size_t size,
gfp_t flags)
{
struct page *page;
......@@ -411,7 +411,7 @@ void * __must_check kasan_kmalloc_large(const void *ptr, size_t size,
return (void *)ptr;
}
void * __must_check kasan_krealloc(const void *object, size_t size, gfp_t flags)
void * __must_check __kasan_krealloc(const void *object, size_t size, gfp_t flags)
{
struct page *page;
......@@ -421,13 +421,13 @@ void * __must_check kasan_krealloc(const void *object, size_t size, gfp_t flags)
page = virt_to_head_page(object);
if (unlikely(!PageSlab(page)))
return kasan_kmalloc_large(object, size, flags);
return __kasan_kmalloc_large(object, size, flags);
else
return __kasan_kmalloc(page->slab_cache, object, size,
return ____kasan_kmalloc(page->slab_cache, object, size,
flags, true);
}
void kasan_poison_kfree(void *ptr, unsigned long ip)
void __kasan_poison_kfree(void *ptr, unsigned long ip)
{
struct page *page;
......@@ -440,11 +440,11 @@ void kasan_poison_kfree(void *ptr, unsigned long ip)
}
kasan_poison_memory(ptr, page_size(page), KASAN_FREE_PAGE);
} else {
__kasan_slab_free(page->slab_cache, ptr, ip, false);
____kasan_slab_free(page->slab_cache, ptr, ip, false);
}
}
void kasan_kfree_large(void *ptr, unsigned long ip)
void __kasan_kfree_large(void *ptr, unsigned long ip)
{
if (ptr != page_address(virt_to_head_page(ptr)))
kasan_report_invalid_free(ptr, ip);
......
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