From 7ed2f9e663854db313f177a511145630e398b402 Mon Sep 17 00:00:00 2001 From: Alexander Potapenko Date: Fri, 25 Mar 2016 14:21:59 -0700 Subject: mm, kasan: SLAB support Add KASAN hooks to SLAB allocator. This patch is based on the "mm: kasan: unified support for SLUB and SLAB allocators" patch originally prepared by Dmitry Chernenkov. Signed-off-by: Alexander Potapenko Cc: Christoph Lameter Cc: Pekka Enberg Cc: David Rientjes Cc: Joonsoo Kim Cc: Andrey Konovalov Cc: Dmitry Vyukov Cc: Andrey Ryabinin Cc: Steven Rostedt Cc: Konstantin Serebryany Cc: Dmitry Chernenkov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/slab.c | 43 +++++++++++++++++++++++++++++++++++++------ 1 file changed, 37 insertions(+), 6 deletions(-) (limited to 'mm/slab.c') diff --git a/mm/slab.c b/mm/slab.c index e719a5cb3396..7515578471d8 100644 --- a/mm/slab.c +++ b/mm/slab.c @@ -2086,6 +2086,8 @@ __kmem_cache_create (struct kmem_cache *cachep, unsigned long flags) } #endif + kasan_cache_create(cachep, &size, &flags); + size = ALIGN(size, cachep->align); /* * We should restrict the number of objects in a slab to implement @@ -2387,8 +2389,13 @@ static void cache_init_objs_debug(struct kmem_cache *cachep, struct page *page) * cache which they are a constructor for. Otherwise, deadlock. * They must also be threaded. */ - if (cachep->ctor && !(cachep->flags & SLAB_POISON)) + if (cachep->ctor && !(cachep->flags & SLAB_POISON)) { + kasan_unpoison_object_data(cachep, + objp + obj_offset(cachep)); cachep->ctor(objp + obj_offset(cachep)); + kasan_poison_object_data( + cachep, objp + obj_offset(cachep)); + } if (cachep->flags & SLAB_RED_ZONE) { if (*dbg_redzone2(cachep, objp) != RED_INACTIVE) @@ -2409,6 +2416,7 @@ static void cache_init_objs(struct kmem_cache *cachep, struct page *page) { int i; + void *objp; cache_init_objs_debug(cachep, page); @@ -2419,8 +2427,12 @@ static void cache_init_objs(struct kmem_cache *cachep, for (i = 0; i < cachep->num; i++) { /* constructor could break poison info */ - if (DEBUG == 0 && cachep->ctor) - cachep->ctor(index_to_obj(cachep, page, i)); + if (DEBUG == 0 && cachep->ctor) { + objp = index_to_obj(cachep, page, i); + kasan_unpoison_object_data(cachep, objp); + cachep->ctor(objp); + kasan_poison_object_data(cachep, objp); + } set_free_obj(page, i, i); } @@ -2550,6 +2562,7 @@ static int cache_grow(struct kmem_cache *cachep, slab_map_pages(cachep, page, freelist); + kasan_poison_slab(page); cache_init_objs(cachep, page); if (gfpflags_allow_blocking(local_flags)) @@ -3316,6 +3329,8 @@ static inline void __cache_free(struct kmem_cache *cachep, void *objp, { struct array_cache *ac = cpu_cache_get(cachep); + kasan_slab_free(cachep, objp); + check_irq_off(); kmemleak_free_recursive(objp, cachep->flags); objp = cache_free_debugcheck(cachep, objp, caller); @@ -3363,6 +3378,7 @@ void *kmem_cache_alloc(struct kmem_cache *cachep, gfp_t flags) { void *ret = slab_alloc(cachep, flags, _RET_IP_); + kasan_slab_alloc(cachep, ret); trace_kmem_cache_alloc(_RET_IP_, ret, cachep->object_size, cachep->size, flags); @@ -3428,6 +3444,7 @@ kmem_cache_alloc_trace(struct kmem_cache *cachep, gfp_t flags, size_t size) ret = slab_alloc(cachep, flags, _RET_IP_); + kasan_kmalloc(cachep, ret, size); trace_kmalloc(_RET_IP_, ret, size, cachep->size, flags); return ret; @@ -3451,6 +3468,7 @@ void *kmem_cache_alloc_node(struct kmem_cache *cachep, gfp_t flags, int nodeid) { void *ret = slab_alloc_node(cachep, flags, nodeid, _RET_IP_); + kasan_slab_alloc(cachep, ret); trace_kmem_cache_alloc_node(_RET_IP_, ret, cachep->object_size, cachep->size, flags, nodeid); @@ -3468,7 +3486,7 @@ void *kmem_cache_alloc_node_trace(struct kmem_cache *cachep, void *ret; ret = slab_alloc_node(cachep, flags, nodeid, _RET_IP_); - + kasan_kmalloc(cachep, ret, size); trace_kmalloc_node(_RET_IP_, ret, size, cachep->size, flags, nodeid); @@ -3481,11 +3499,15 @@ static __always_inline void * __do_kmalloc_node(size_t size, gfp_t flags, int node, unsigned long caller) { struct kmem_cache *cachep; + void *ret; cachep = kmalloc_slab(size, flags); if (unlikely(ZERO_OR_NULL_PTR(cachep))) return cachep; - return kmem_cache_alloc_node_trace(cachep, flags, node, size); + ret = kmem_cache_alloc_node_trace(cachep, flags, node, size); + kasan_kmalloc(cachep, ret, size); + + return ret; } void *__kmalloc_node(size_t size, gfp_t flags, int node) @@ -3519,6 +3541,7 @@ static __always_inline void *__do_kmalloc(size_t size, gfp_t flags, return cachep; ret = slab_alloc(cachep, flags, caller); + kasan_kmalloc(cachep, ret, size); trace_kmalloc(caller, ret, size, cachep->size, flags); @@ -4290,10 +4313,18 @@ module_init(slab_proc_init); */ size_t ksize(const void *objp) { + size_t size; + BUG_ON(!objp); if (unlikely(objp == ZERO_SIZE_PTR)) return 0; - return virt_to_cache(objp)->object_size; + size = virt_to_cache(objp)->object_size; + /* We assume that ksize callers could use the whole allocated area, + * so we need to unpoison this area. + */ + kasan_krealloc(objp, size); + + return size; } EXPORT_SYMBOL(ksize); -- cgit v1.2.3-55-g7522