Commit f372bde9 authored by Andrey Konovalov's avatar Andrey Konovalov Committed by Andrew Morton
Browse files

kasan: only define kasan_metadata_size for Generic mode 

KASAN provides a helper for calculating the size of per-object metadata
stored in the redzone.

As now only the Generic mode uses per-object metadata, only define
kasan_metadata_size() for this mode.

Link: https://lkml.kernel.org/r/8f81d4938b80446bc72538a08217009f328a3e23.1662411799.git.andreyknvl@google.com


Signed-off-by: default avatarAndrey Konovalov <andreyknvl@google.com>
Reviewed-by: default avatarMarco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Peter Collingbourne <pcc@google.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent 02856beb

include/linux/kasan.h

+8 −9
Original line number Diff line number Diff line
@@ -150,14 +150,6 @@ static __always_inline void kasan_cache_create_kmalloc(struct kmem_cache *cache) 
		__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 slab *slab);

static __always_inline void kasan_poison_slab(struct slab *slab)

{
@@ -282,7 +274,6 @@ 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 slab *slab) {}

static inline void kasan_unpoison_object_data(struct kmem_cache *cache,

					void *object) {}
@@ -333,6 +324,8 @@ static inline void kasan_unpoison_task_stack(struct task_struct *task) {} 


#ifdef CONFIG_KASAN_GENERIC



size_t kasan_metadata_size(struct kmem_cache *cache);



void kasan_cache_shrink(struct kmem_cache *cache);

void kasan_cache_shutdown(struct kmem_cache *cache);

void kasan_record_aux_stack(void *ptr);
@@ -340,6 +333,12 @@ void kasan_record_aux_stack_noalloc(void *ptr); 


#else /* CONFIG_KASAN_GENERIC */



/* Tag-based KASAN modes do not use per-object metadata. */

static inline size_t kasan_metadata_size(struct kmem_cache *cache)

{

	return 0;

}



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) {}

mm/kasan/common.c

+0 −11
Original line number Diff line number Diff line
@@ -139,17 +139,6 @@ void __kasan_cache_create_kmalloc(struct kmem_cache *cache) 
	cache->kasan_info.is_kmalloc = true;

}



size_t __kasan_metadata_size(struct kmem_cache *cache)

{

	if (!kasan_requires_meta())

		return 0;

	return (cache->kasan_info.alloc_meta_offset ?

		sizeof(struct kasan_alloc_meta) : 0) +

		((cache->kasan_info.free_meta_offset &&

		  cache->kasan_info.free_meta_offset != KASAN_NO_FREE_META) ?

		 sizeof(struct kasan_free_meta) : 0);

}



void __kasan_poison_slab(struct slab *slab)

{

	struct page *page = slab_page(slab);

mm/kasan/generic.c

+11 −0
Original line number Diff line number Diff line
@@ -427,6 +427,17 @@ void kasan_init_object_meta(struct kmem_cache *cache, const void *object) 
		__memset(alloc_meta, 0, sizeof(*alloc_meta));

}



size_t kasan_metadata_size(struct kmem_cache *cache)

{

	if (!kasan_requires_meta())

		return 0;

	return (cache->kasan_info.alloc_meta_offset ?

		sizeof(struct kasan_alloc_meta) : 0) +

		((cache->kasan_info.free_meta_offset &&

		  cache->kasan_info.free_meta_offset != KASAN_NO_FREE_META) ?

		 sizeof(struct kasan_free_meta) : 0);

}



static void __kasan_record_aux_stack(void *addr, bool can_alloc)

{

	struct slab *slab = kasan_addr_to_slab(addr);