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=-4.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 39B96C04AAF for ; Fri, 17 May 2019 01:26:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 027EF2082E for ; Fri, 17 May 2019 01:26:25 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="QNQxNc5y" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726879AbfEQB0Z (ORCPT ); Thu, 16 May 2019 21:26:25 -0400 Received: from mail-pf1-f194.google.com ([209.85.210.194]:45300 "EHLO mail-pf1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726839AbfEQB0Z (ORCPT ); Thu, 16 May 2019 21:26:25 -0400 Received: by mail-pf1-f194.google.com with SMTP id s11so2764100pfm.12 for ; Thu, 16 May 2019 18:26:24 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=+cJ2gxhZLau5gmuenPlTtxJhsl5TXn8iu9yGe1AQQrg=; b=QNQxNc5ypRwtdFSH6HpSYR0MThc0HpZETeuvrI6NSQk2We0nlIfd3RF8xLG1Ydb5Ni C7l69sF2b+zwXTu+27LDKNH02FrrDRkffXWwiX6s9n+JvtV+SEbf828xWCOVEFv3hlWv U1gbvwBvIrttUqNQjSQ0XLYWgiKZYmbIip2B8= 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; bh=+cJ2gxhZLau5gmuenPlTtxJhsl5TXn8iu9yGe1AQQrg=; b=m1sM8eOh0RWwnXOwV8jT7BX1F8y6fcM3QieR+fmJ1vIG9R7EeC6QOqhKNjn2FDeQVP nXZ5d8oSx6mteTE6jdrnIqMc9/UXvY4kgoODJL66rSAzQdMv4g/d4KS7nEwf6w1fgAup /iNXO4ATYC7IM5O1Zyo2BxU5zrEGEGECNIzIt2HnQH2Qg4IACSWUYIBUO4eVhayLVpB9 1LmBflnQiFHnfkDQ7xJ3OEnt8rXWzu7fPcrV21o0N+11L4NZ5V0Qc8gJJJllNvRKSzqF v6KPOle9ctOUga1fxi37XlzHStYboUbY2mWCxiY+NnbIazk25FxxIEcDuqx+QflXsZRA BvFg== X-Gm-Message-State: APjAAAW5QVcj3dsGHa7oiFL/EikmNaV9+qw2Ax9dvf8fVGhsOzh4PzdR vKyVnuz8grlNscmJJPNP+iLnKQ== X-Google-Smtp-Source: APXvYqz3bg5gRNoTrwMyo5+vXZ7qa4nbJU852Lnd6zCfw82/d5ftsiATgeUm4vLixEXP76pwv/yJLQ== X-Received: by 2002:a63:1a03:: with SMTP id a3mr54079259pga.412.1558056384345; Thu, 16 May 2019 18:26:24 -0700 (PDT) Received: from www.outflux.net (smtp.outflux.net. [198.145.64.163]) by smtp.gmail.com with ESMTPSA id u11sm7829530pfh.130.2019.05.16.18.26.22 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Thu, 16 May 2019 18:26:23 -0700 (PDT) Date: Thu, 16 May 2019 18:26:22 -0700 From: Kees Cook To: Alexander Potapenko Cc: akpm@linux-foundation.org, cl@linux.com, kernel-hardening@lists.openwall.com, Masahiro Yamada , James Morris , "Serge E. Hallyn" , Nick Desaulniers , Kostya Serebryany , Dmitry Vyukov , Sandeep Patil , Laura Abbott , Randy Dunlap , Jann Horn , Mark Rutland , linux-mm@kvack.org, linux-security-module@vger.kernel.org Subject: Re: [PATCH v2 1/4] mm: security: introduce init_on_alloc=1 and init_on_free=1 boot options Message-ID: <201905161824.63B0DF0E@keescook> References: <20190514143537.10435-1-glider@google.com> <20190514143537.10435-2-glider@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190514143537.10435-2-glider@google.com> Sender: owner-linux-security-module@vger.kernel.org Precedence: bulk List-ID: On Tue, May 14, 2019 at 04:35:34PM +0200, Alexander Potapenko wrote: > [...] > diff --git a/mm/slab.h b/mm/slab.h > index 43ac818b8592..24ae887359b8 100644 > --- a/mm/slab.h > +++ b/mm/slab.h > @@ -524,4 +524,20 @@ static inline int cache_random_seq_create(struct kmem_cache *cachep, > [...] > +static inline bool slab_want_init_on_free(struct kmem_cache *c) > +{ > + if (static_branch_unlikely(&init_on_free)) > + return !(c->ctor); BTW, why is this checking for c->ctor here? Shouldn't it not matter for the free case? > + else > + return false; > +} -- Kees Cook