From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-18.9 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1,USER_IN_DEF_DKIM_WL autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3E886C388F9 for ; Wed, 11 Nov 2020 19:17:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id CA5C420797 for ; Wed, 11 Nov 2020 19:17:40 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="JyMoM46i" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727407AbgKKTRj (ORCPT ); Wed, 11 Nov 2020 14:17:39 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51016 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726134AbgKKTRj (ORCPT ); Wed, 11 Nov 2020 14:17:39 -0500 Received: from mail-wr1-x441.google.com (mail-wr1-x441.google.com [IPv6:2a00:1450:4864:20::441]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3C776C0613D1 for ; Wed, 11 Nov 2020 11:17:39 -0800 (PST) Received: by mail-wr1-x441.google.com with SMTP id 33so3614161wrl.7 for ; Wed, 11 Nov 2020 11:17:39 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=kMrBNTvUl7eFEy433Sc7HrH1xnZw22qMO0dPs+XlBag=; b=JyMoM46iSDFsiDKvjg0YoviV0jxdDbSXOIqKDrRqUpzPy5au4hhoa98Y41MM6Zvn69 7Jo7UIkvwH3Ssuk43BJjXiFJ30PzNeTzt6VQEDgS0UwANh5P/1eNNysQ7BCB1DU1ltNA 2w0SR9iG3ajokKf/91XnJPozzUdEco8sod6U2zQPgbxu+FpKcu1x7s6va8ks253wNNIe Jr5TSykdUc/F6Ev77gVW8ceTL9fJe/w9SWAp89YLMUEDCdO31Lx0CxCq2AmKxoBpNnBl zfhFcjuUBjC+N2SGYOmcib6r+rWZmpuUf6pSiFR0DbUaSYTtCPNSWeVXQXrv+I6hwBVK XHnA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=kMrBNTvUl7eFEy433Sc7HrH1xnZw22qMO0dPs+XlBag=; b=XpRNcgFzQlGtccjE2ZXnqxQHfYSAPRR38CqiiO+CXh8sk72uhSyxtn2U8j4Tt2/g3e yL+ji5H0zD6DMZJ5adVEmxnfxCVKD46LQ5fGuBeEkETW4qRK4ABKMzKq2iaxXIsJZRio 1AyBgtDyHCnG+oNp9MBweno1/7KzYvnkK3hcZSdcpfaZMO/AysJLn9JapvNeuQ0IVSlG JobTSYAlgD1lrA+ldd4JBKoI/7fwy/dK9y4ZlDOAJ6IOa3vHoL2iUsyjor6uQ26b1/50 xn9heRE8QiXsFXk++0t4uwQ+qiImVk4wxpZjscxI3loV0ZlcKmBm+1SJwgF6bZqpMDAG V64g== X-Gm-Message-State: AOAM530oHt+Wyu1BZqy0VAER9Oq6wJTr0SCS2AShxJt2OuvKabXuDGBY 9141FskZFgsE4VbIJ3cg3pUVWA== X-Google-Smtp-Source: ABdhPJyDmF5o/EhHUlAWnTV5B9M/0BDsYvV61vd+CfOa8MeLPXuw8/vrzkyo+MVG1df4JWcvaJhoFg== X-Received: by 2002:adf:93e1:: with SMTP id 88mr30294553wrp.37.1605122257781; Wed, 11 Nov 2020 11:17:37 -0800 (PST) Received: from elver.google.com ([2a00:79e0:15:13:f693:9fff:fef4:2449]) by smtp.gmail.com with ESMTPSA id b1sm3833382wmd.43.2020.11.11.11.17.36 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 11 Nov 2020 11:17:36 -0800 (PST) Date: Wed, 11 Nov 2020 20:17:31 +0100 From: Marco Elver To: Andrey Konovalov Cc: Dmitry Vyukov , Alexander Potapenko , Catalin Marinas , Will Deacon , Vincenzo Frascino , Evgenii Stepanov , Andrey Ryabinin , Branislav Rankov , Kevin Brodsky , Andrew Morton , kasan-dev@googlegroups.com, linux-arm-kernel@lists.infradead.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 16/20] kasan: simplify assign_tag and set_tag calls Message-ID: <20201111191731.GR517454@elver.google.com> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.14.6 (2020-07-11) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Nov 10, 2020 at 11:20PM +0100, Andrey Konovalov wrote: > set_tag() already ignores the tag for the generic mode, so just call it > as is. Add a check for the generic mode to assign_tag(), and simplify its > call in ____kasan_kmalloc(). > > Signed-off-by: Andrey Konovalov > Reviewed-by: Dmitry Vyukov > Link: https://linux-review.googlesource.com/id/I18905ca78fb4a3d60e1a34a4ca00247272480438 > --- > mm/kasan/common.c | 11 ++++++----- > 1 file changed, 6 insertions(+), 5 deletions(-) Reviewed-by: Marco Elver > diff --git a/mm/kasan/common.c b/mm/kasan/common.c > index 69ab880abacc..40ff3ce07a76 100644 > --- a/mm/kasan/common.c > +++ b/mm/kasan/common.c > @@ -238,6 +238,9 @@ void __kasan_poison_object_data(struct kmem_cache *cache, void *object) > static u8 assign_tag(struct kmem_cache *cache, const void *object, > bool init, bool keep_tag) > { > + if (IS_ENABLED(CONFIG_KASAN_GENERIC)) > + return 0xff; > + Hopefully the compiler is clever enough to start inlining this function. > /* > * 1. When an object is kmalloc()'ed, two hooks are called: > * kasan_slab_alloc() and kasan_kmalloc(). We assign the > @@ -280,8 +283,8 @@ void * __must_check __kasan_init_slab_obj(struct kmem_cache *cache, > __memset(alloc_meta, 0, sizeof(*alloc_meta)); > } > > - if (IS_ENABLED(CONFIG_KASAN_SW_TAGS) || IS_ENABLED(CONFIG_KASAN_HW_TAGS)) > - object = set_tag(object, assign_tag(cache, object, true, false)); > + /* Tag is ignored in set_tag() without CONFIG_KASAN_SW/HW_TAGS */ > + object = set_tag(object, assign_tag(cache, object, true, false)); > > return (void *)object; > } > @@ -362,9 +365,7 @@ static void *____kasan_kmalloc(struct kmem_cache *cache, const void *object, > KASAN_GRANULE_SIZE); > redzone_end = round_up((unsigned long)object + cache->object_size, > KASAN_GRANULE_SIZE); > - > - if (IS_ENABLED(CONFIG_KASAN_SW_TAGS) || IS_ENABLED(CONFIG_KASAN_HW_TAGS)) > - tag = assign_tag(cache, object, false, keep_tag); > + tag = assign_tag(cache, object, false, keep_tag); > The definition of 'tag' at the start of ____kasan_kmalloc() no longer needs an initializer. > /* Tag is ignored in set_tag without CONFIG_KASAN_SW/HW_TAGS */ > kasan_unpoison_memory(set_tag(object, tag), size);