mm/kasan/common.c

156 void __kasan_unpoison_new_object(struct kmem_cache *cache, void *object)
158 	kasan_unpoison(object, cache->object_size, false);
161 void __kasan_poison_new_object(struct kmem_cache *cache, void *object)
163 	kasan_poison(object, round_up(cache->object_size, KASAN_GRANULE_SIZE),
168  * This function assigns a tag to an object considering the following:
170  *    object somewhere (e.g. in the object itself). We preassign a tag for
171  *    each object in caches with constructors during slab creation and reuse
172  *    the same tag each time a particular object is allocated.
178 					const void *object, bool init)
185 	 * set, assign a tag when the object is being allocated (init == false).
195 	return init ? kasan_random_tag() : get_tag(object);
199 						const void *object)
201 	/* Initialize per-object metadata if it is present. */
203 		kasan_init_object_meta(cache, object);
206 	object = set_tag(object, assign_tag(cache, object, true));
208 	return (void *)object;
211 static inline bool poison_slab_object(struct kmem_cache *cache, void *object,
219 	tagged_object = object;
220 	object = kasan_reset_tag(object);
222 	if (unlikely(nearest_obj(cache, virt_to_slab(object), object) != object)) {
236 	kasan_poison(object, round_up(cache->object_size, KASAN_GRANULE_SIZE),
245 bool __kasan_slab_free(struct kmem_cache *cache, void *object,
248 	if (is_kfence_address(object))
252 	 * If the object is buggy, do not let slab put the object onto the
253 	 * freelist. The object will thus never be allocated again and its
256 	if (poison_slab_object(cache, object, ip, init))
260 	 * If the object is put into quarantine, do not let slab put the object
261 	 * onto the freelist for now. The object's metadata is kept until the
262 	 * object gets evicted from quarantine.
264 	if (kasan_quarantine_put(cache, object))
268 	 * Note: Keep per-object metadata to allow KASAN print stack traces for
272 	/* Let slab put the object onto the freelist. */
298 	/* The object will be poisoned by kasan_poison_pages(). */
301 static inline void unpoison_slab_object(struct kmem_cache *cache, void *object,
305 	 * Unpoison the whole object. For kmalloc() allocations,
308 	kasan_unpoison(object, cache->object_size, init);
312 		kasan_save_alloc_info(cache, object, flags);
316 					void *object, gfp_t flags, bool init)
324 	if (unlikely(object == NULL))
327 	if (is_kfence_address(object))
328 		return (void *)object;
334 	tag = assign_tag(cache, object, false);
335 	tagged_object = set_tag(object, tag);
337 	/* Unpoison the object and save alloc info for non-kmalloc() allocations. */
344 				const void *object, size_t size, gfp_t flags)
351 	 * Partially poison the last object granule to cover the unaligned
355 		kasan_poison_last_granule((void *)object, size);
358 	redzone_start = round_up((unsigned long)(object + size),
360 	redzone_end = round_up((unsigned long)(object + cache->object_size),
370 		kasan_save_alloc_info(cache, (void *)object, flags);
374 void * __must_check __kasan_kmalloc(struct kmem_cache *cache, const void *object,
380 	if (unlikely(object == NULL))
383 	if (is_kfence_address(object))
384 		return (void *)object;
386 	/* The object has already been unpoisoned by kasan_slab_alloc(). */
387 	poison_kmalloc_redzone(cache, object, size, flags);
390 	return (void *)object;
402 	 * Partially poison the last object granule to cover the unaligned
424 	/* The object has already been unpoisoned by kasan_unpoison_pages(). */
431 void * __must_check __kasan_krealloc(const void *object, size_t size, gfp_t flags)
438 	if (unlikely(object == ZERO_SIZE_PTR))
439 		return (void *)object;
441 	if (is_kfence_address(object))
442 		return (void *)object;
445 	 * Unpoison the object's data.
449 	kasan_unpoison(object, size, false);
451 	slab = virt_to_slab(object);
455 		poison_kmalloc_large_redzone(object, size, flags);
457 		poison_kmalloc_redzone(slab->slab_cache, object, size, flags);
459 	return (void *)object;
534 	/* Unpoison the object and save alloc info for non-kmalloc() allocations. */