From 682ed08924407b719fa0b1123a26971748d76ace Mon Sep 17 00:00:00 2001 From: Andrey Konovalov <andreyknvl@google.com> Date: Mon, 5 Sep 2022 23:05:33 +0200 Subject: kasan: only define kasan_cache_create for Generic mode Right now, kasan_cache_create() assigns SLAB_KASAN for all KASAN modes and then sets up metadata-related cache parameters for the Generic mode. SLAB_KASAN is used in two places: 1. In slab_ksize() to account for per-object metadata when calculating the size of the accessible memory within the object. 2. In slab_common.c via kasan_never_merge() to prevent merging of caches with per-object metadata. Both cases are only relevant when per-object metadata is present, which is only the case with the Generic mode. Thus, assign SLAB_KASAN and define kasan_cache_create() only for the Generic mode. Also update the SLAB_KASAN-related comment. Link: https://lkml.kernel.org/r/61faa2aa1906e2d02c97d00ddf99ce8911dda095.1662411799.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 <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: Andrew Morton <akpm@linux-foundation.org> --- include/linux/kasan.h | 18 ++++++------------ 1 file changed, 6 insertions(+), 12 deletions(-) (limited to 'include/linux/kasan.h') diff --git a/include/linux/kasan.h b/include/linux/kasan.h index a212c2e3f32d..d811b3d7d2a1 100644 --- a/include/linux/kasan.h +++ b/include/linux/kasan.h @@ -128,15 +128,6 @@ static __always_inline void kasan_unpoison_pages(struct page *page, __kasan_unpoison_pages(page, order, init); } -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) { @@ -260,9 +251,6 @@ static inline void kasan_poison_pages(struct page *page, unsigned int order, bool init) {} static inline void kasan_unpoison_pages(struct page *page, unsigned int order, bool init) {} -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 void kasan_poison_slab(struct slab *slab) {} static inline void kasan_unpoison_object_data(struct kmem_cache *cache, @@ -316,6 +304,8 @@ static inline void kasan_unpoison_task_stack(struct task_struct *task) {} size_t kasan_metadata_size(struct kmem_cache *cache); slab_flags_t kasan_never_merge(void); +void kasan_cache_create(struct kmem_cache *cache, unsigned int *size, + slab_flags_t *flags); void kasan_cache_shrink(struct kmem_cache *cache); void kasan_cache_shutdown(struct kmem_cache *cache); @@ -334,6 +324,10 @@ 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, + slab_flags_t *flags) {} static inline void kasan_cache_shrink(struct kmem_cache *cache) {} static inline void kasan_cache_shutdown(struct kmem_cache *cache) {} -- cgit v1.2.3