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,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no 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 1C3D7C433DF for ; Mon, 22 Jun 2020 21:26:47 +0000 (UTC) Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.kernel.org (Postfix) with SMTP id 6BC6A20732 for ; Mon, 22 Jun 2020 21:26:46 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="J00hIsrX" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6BC6A20732 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=chromium.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kernel-hardening-return-19043-kernel-hardening=archiver.kernel.org@lists.openwall.com Received: (qmail 5969 invoked by uid 550); 22 Jun 2020 21:26:40 -0000 Mailing-List: contact kernel-hardening-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Received: (qmail 5931 invoked from network); 22 Jun 2020 21:26:39 -0000 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=+fGVHQGbJSfeZpDFh+8/BeMq0iFulsSXIRYour5Vm0w=; b=J00hIsrXU7lUbB9T6uH+6OCvgVWQVpgD3QI0ZPH4Hk8LTAUfUiRewvjxyBQzGiD1ve iFnCJBgzFqit6FhHqe5BM8n1JJmg8rHtVkq3RtopnM4OgUUVSs4z5vEKGujmdV8eaHzg QPi3H0BTKGLlJqCPNPE+nQs3/vQLHDYWXLkWY= 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=+fGVHQGbJSfeZpDFh+8/BeMq0iFulsSXIRYour5Vm0w=; b=tDOQ7Jk+TjdXqUbM0+UvCCZ3ypcvxaKaj3OQ//hqyBe+HwoVSdUwauy+6wiD4gT0tk ml6Lv9ZnchB7QSNCQLP90111nOrsOmuqULraZWbNx37FbpwiQE9si3B35+U0REEybwx0 uf5kJ3W60djjfCxZg4pZwSJ8XX/twGetwzuRiNDJ62SLtFWOfXS1Ojq3Lt7LOjqCweqb eO3Ahs4gIiX88dEEMVKk9pmjiMSEgN3iLVbaDH95WvgsxNVXNYbMpVqc58TkCDFM/BkY du7KpweHoEATcxJhUSSLyYYYKBpXS0mVDqGFofyvMIxE/Y1X3Gzmdf9/pMKE+LVN5uI3 73qw== X-Gm-Message-State: AOAM532bcF4Jq4sEf+DNi8vNe+9fmKAdgS/aJZrFBRulj983C+8mBcqA BglTy7K2dsz4+NqaMFYcz9q6wg== X-Google-Smtp-Source: ABdhPJz9FSwoUGnk0FK8dRtqojR7DRsccJU6Ok7KN9Xp0A18XOCuQ0Au72MfAI1gfeRNqQL2b31VvQ== X-Received: by 2002:aa7:8a4c:: with SMTP id n12mr22059315pfa.326.1592861187688; Mon, 22 Jun 2020 14:26:27 -0700 (PDT) Date: Mon, 22 Jun 2020 14:26:25 -0700 From: Kees Cook To: Randy Dunlap Cc: Thomas Gleixner , Elena Reshetova , x86@kernel.org, Andy Lutomirski , Peter Zijlstra , Catalin Marinas , Will Deacon , Mark Rutland , Alexander Potapenko , Alexander Popov , Ard Biesheuvel , Jann Horn , kernel-hardening@lists.openwall.com, linux-arm-kernel@lists.infradead.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v4 3/5] stack: Optionally randomize kernel stack offset each syscall Message-ID: <202006221425.805E17B67@keescook> References: <20200622193146.2985288-1-keescook@chromium.org> <20200622193146.2985288-4-keescook@chromium.org> <87a7b943-ed15-8521-773e-c182a37ee61e@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <87a7b943-ed15-8521-773e-c182a37ee61e@infradead.org> On Mon, Jun 22, 2020 at 12:40:49PM -0700, Randy Dunlap wrote: > On 6/22/20 12:31 PM, Kees Cook wrote: > > This provides the ability for architectures to enable kernel stack base > > address offset randomization. This feature is controlled by the boot > > param "randomize_kstack_offset=on/off", with its default value set by > > CONFIG_RANDOMIZE_KSTACK_OFFSET_DEFAULT. > > > > Co-developed-by: Elena Reshetova > > Signed-off-by: Elena Reshetova > > Link: https://lore.kernel.org/r/20190415060918.3766-1-elena.reshetova@intel.com > > Signed-off-by: Kees Cook > > --- > > Makefile | 4 ++++ > > arch/Kconfig | 23 ++++++++++++++++++ > > include/linux/randomize_kstack.h | 40 ++++++++++++++++++++++++++++++++ > > init/main.c | 23 ++++++++++++++++++ > > 4 files changed, 90 insertions(+) > > create mode 100644 include/linux/randomize_kstack.h > > Please add documentation for the new kernel boot parameter to > Documentation/admin-guide/kernel-parameters.txt. Oops, yes. Thanks for the reminder! (I wonder if checkpatch can notice "+early_param" and suggest the Doc update hmmm) -- Kees Cook