From nobody Wed Dec 31 08:47:56 2025 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7A185C4332F for ; Mon, 6 Nov 2023 20:14:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233127AbjKFUOc (ORCPT ); Mon, 6 Nov 2023 15:14:32 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52224 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233126AbjKFUOG (ORCPT ); Mon, 6 Nov 2023 15:14:06 -0500 Received: from out-186.mta0.migadu.com (out-186.mta0.migadu.com [IPv6:2001:41d0:1004:224b::ba]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B2AB7173D for ; Mon, 6 Nov 2023 12:13:51 -0800 (PST) X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1699301629; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=FAC2S7cvKWC0F44BA8JFK/nUEMkMZjl2M4MUzuWuDcc=; b=gW/TzhDfZHPF/6G1OrNDQlLOWzEZX/fdM1cYbnvPQJyE+kylQJLDKf+bdGnEZPKJYJFBTJ 4QEyp11eHyzBaGYnGOiz5gn3Q6Jl2PEmI90MIeHA3Z1ZMwOIDu2AEjJhNEEem2iCH7tksZ EO/mX3B4YVf6+hMEYQMPvEmF3YvoFx4= From: andrey.konovalov@linux.dev To: Marco Elver , Alexander Potapenko Cc: Andrey Konovalov , Dmitry Vyukov , Andrey Ryabinin , kasan-dev@googlegroups.com, Evgenii Stepanov , Andrew Morton , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Andrey Konovalov Subject: [PATCH RFC 18/20] kasan: rename and document kasan_(un)poison_object_data Date: Mon, 6 Nov 2023 21:10:27 +0100 Message-Id: <1128fd5cf1051270bc7e5978479a983a918626f5.1699297309.git.andreyknvl@google.com> In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Migadu-Flow: FLOW_OUT Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" From: Andrey Konovalov Rename kasan_unpoison_object_data to kasan_unpoison_new_object and add a documentation comment. Do the same for kasan_poison_object_data. The new names and the comments should suggest the users that these hooks are intended for internal use by the slab allocator. The following patch will remove non-slab-internal uses of these hooks. No functional changes. Signed-off-by: Andrey Konovalov --- include/linux/kasan.h | 35 +++++++++++++++++++++++++++-------- mm/kasan/common.c | 4 ++-- mm/slab.c | 10 ++++------ mm/slub.c | 4 ++-- net/core/skbuff.c | 8 ++++---- 5 files changed, 39 insertions(+), 22 deletions(-) diff --git a/include/linux/kasan.h b/include/linux/kasan.h index 7392c5d89b92..d49e3d4c099e 100644 --- a/include/linux/kasan.h +++ b/include/linux/kasan.h @@ -129,20 +129,39 @@ static __always_inline void kasan_poison_slab(struct = slab *slab) __kasan_poison_slab(slab); } =20 -void __kasan_unpoison_object_data(struct kmem_cache *cache, void *object); -static __always_inline void kasan_unpoison_object_data(struct kmem_cache *= cache, +void __kasan_unpoison_new_object(struct kmem_cache *cache, void *object); +/** + * kasan_unpoison_new_object - Temporarily unpoison a new slab object. + * @cache: Cache the object belong to. + * @object: Pointer to the object. + * + * This function is intended for the slab allocator's internal use. It + * temporarily unpoisons an object from a newly allocated slab without doi= ng + * anything else. The object must later be repoisoned by + * kasan_poison_new_object(). + */ +static __always_inline void kasan_unpoison_new_object(struct kmem_cache *c= ache, void *object) { if (kasan_enabled()) - __kasan_unpoison_object_data(cache, object); + __kasan_unpoison_new_object(cache, object); } =20 -void __kasan_poison_object_data(struct kmem_cache *cache, void *object); -static __always_inline void kasan_poison_object_data(struct kmem_cache *ca= che, +void __kasan_poison_new_object(struct kmem_cache *cache, void *object); +/** + * kasan_unpoison_new_object - Repoison a new slab object. + * @cache: Cache the object belong to. + * @object: Pointer to the object. + * + * This function is intended for the slab allocator's internal use. It + * repoisons an object that was previously unpoisoned by + * kasan_unpoison_new_object() without doing anything else. + */ +static __always_inline void kasan_poison_new_object(struct kmem_cache *cac= he, void *object) { if (kasan_enabled()) - __kasan_poison_object_data(cache, object); + __kasan_poison_new_object(cache, object); } =20 void * __must_check __kasan_init_slab_obj(struct kmem_cache *cache, @@ -342,9 +361,9 @@ static inline bool kasan_unpoison_pages(struct page *pa= ge, unsigned int order, return false; } static inline void kasan_poison_slab(struct slab *slab) {} -static inline void kasan_unpoison_object_data(struct kmem_cache *cache, +static inline void kasan_unpoison_new_object(struct kmem_cache *cache, void *object) {} -static inline void kasan_poison_object_data(struct kmem_cache *cache, +static inline void kasan_poison_new_object(struct kmem_cache *cache, void *object) {} static inline void *kasan_init_slab_obj(struct kmem_cache *cache, const void *object) diff --git a/mm/kasan/common.c b/mm/kasan/common.c index 65850d37fd27..9f11be6b00a8 100644 --- a/mm/kasan/common.c +++ b/mm/kasan/common.c @@ -133,12 +133,12 @@ void __kasan_poison_slab(struct slab *slab) KASAN_SLAB_REDZONE, false); } =20 -void __kasan_unpoison_object_data(struct kmem_cache *cache, void *object) +void __kasan_unpoison_new_object(struct kmem_cache *cache, void *object) { kasan_unpoison(object, cache->object_size, false); } =20 -void __kasan_poison_object_data(struct kmem_cache *cache, void *object) +void __kasan_poison_new_object(struct kmem_cache *cache, void *object) { kasan_poison(object, round_up(cache->object_size, KASAN_GRANULE_SIZE), KASAN_SLAB_REDZONE, false); diff --git a/mm/slab.c b/mm/slab.c index 9ad3d0f2d1a5..773c79e153f3 100644 --- a/mm/slab.c +++ b/mm/slab.c @@ -2327,11 +2327,9 @@ static void cache_init_objs_debug(struct kmem_cache = *cachep, struct slab *slab) * They must also be threaded. */ if (cachep->ctor && !(cachep->flags & SLAB_POISON)) { - kasan_unpoison_object_data(cachep, - objp + obj_offset(cachep)); + kasan_unpoison_new_object(cachep, objp + obj_offset(cachep)); cachep->ctor(objp + obj_offset(cachep)); - kasan_poison_object_data( - cachep, objp + obj_offset(cachep)); + kasan_poison_new_object(cachep, objp + obj_offset(cachep)); } =20 if (cachep->flags & SLAB_RED_ZONE) { @@ -2472,9 +2470,9 @@ static void cache_init_objs(struct kmem_cache *cachep, =20 /* constructor could break poison info */ if (DEBUG =3D=3D 0 && cachep->ctor) { - kasan_unpoison_object_data(cachep, objp); + kasan_unpoison_new_object(cachep, objp); cachep->ctor(objp); - kasan_poison_object_data(cachep, objp); + kasan_poison_new_object(cachep, objp); } =20 if (!shuffled) diff --git a/mm/slub.c b/mm/slub.c index 63d281dfacdb..973f091ec5d1 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -1849,9 +1849,9 @@ static void *setup_object(struct kmem_cache *s, void = *object) setup_object_debug(s, object); object =3D kasan_init_slab_obj(s, object); if (unlikely(s->ctor)) { - kasan_unpoison_object_data(s, object); + kasan_unpoison_new_object(s, object); s->ctor(object); - kasan_poison_object_data(s, object); + kasan_poison_new_object(s, object); } return object; } diff --git a/net/core/skbuff.c b/net/core/skbuff.c index b157efea5dea..63bb6526399d 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -337,7 +337,7 @@ static struct sk_buff *napi_skb_cache_get(void) } =20 skb =3D nc->skb_cache[--nc->skb_count]; - kasan_unpoison_object_data(skbuff_cache, skb); + kasan_unpoison_new_object(skbuff_cache, skb); =20 return skb; } @@ -1309,13 +1309,13 @@ static void napi_skb_cache_put(struct sk_buff *skb) struct napi_alloc_cache *nc =3D this_cpu_ptr(&napi_alloc_cache); u32 i; =20 - kasan_poison_object_data(skbuff_cache, skb); + kasan_poison_new_object(skbuff_cache, skb); nc->skb_cache[nc->skb_count++] =3D skb; =20 if (unlikely(nc->skb_count =3D=3D NAPI_SKB_CACHE_SIZE)) { for (i =3D NAPI_SKB_CACHE_HALF; i < NAPI_SKB_CACHE_SIZE; i++) - kasan_unpoison_object_data(skbuff_cache, - nc->skb_cache[i]); + kasan_unpoison_new_object(skbuff_cache, + nc->skb_cache[i]); =20 kmem_cache_free_bulk(skbuff_cache, NAPI_SKB_CACHE_HALF, nc->skb_cache + NAPI_SKB_CACHE_HALF); --=20 2.25.1