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=-7.0 required=3.0 tests=DKIMWL_WL_HIGH,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 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 314CEC2BA1E for ; Mon, 6 Apr 2020 18:25:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 112A2206C3 for ; Mon, 6 Apr 2020 18:25:43 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="SDponCt4" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726670AbgDFSZl (ORCPT ); Mon, 6 Apr 2020 14:25:41 -0400 Received: from mail-pf1-f193.google.com ([209.85.210.193]:44523 "EHLO mail-pf1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726620AbgDFSZl (ORCPT ); Mon, 6 Apr 2020 14:25:41 -0400 Received: by mail-pf1-f193.google.com with SMTP id b72so7965984pfb.11 for ; Mon, 06 Apr 2020 11:25:39 -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=9XYlLQFnWWwdu63sAOZZGoKgEJL0Ub8ZWN6C/xE+U6U=; b=SDponCt4iCqvCfanCAa+3pMV+vTOM+mT//ho9jt22D8PbBsbH2TJbTcKnPOBjtwXoZ SQGfpcE+gQXFzNGbuAmAiUIxrWnTfyp79v9RE+eyo4jV4iEqo5Rzj6koUCpF2IQ8lEGG y96wsJ90XGooCKj5qCos/vO8fxQnHFE8YVifk= 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=9XYlLQFnWWwdu63sAOZZGoKgEJL0Ub8ZWN6C/xE+U6U=; b=Y2+IibczNmkHTEbZ+Vi6Bra4YwkeCPYudeWlc4T5M2LXBiIYAli9D0ofYXCmrU8Z5i 8z1rfWjg375twS+Mo+RRn/gXfyZUfVrZMQCK+hwabU+ahHMpniCRifuPeKBpxl1ydxWY r0BzmtD5/LKxPLMQvBsn+76Nb8AknpruqUSe7dAirP65mVHmQCQbAT8J7TzsTajFQ4vg b1h0QtU4Enk7s45zp6ftKlLOEfv0hRZaxqTXoprK8GaAfOm6F3OunI/1NyUtB3dAFZ9B W5ZnvYHgyYxQ7OS+AukCmgZNpodZ55s7Z36zWdWHvSLDlZr8IJ9ZdLFYbDK4H7nyheHh EbGA== X-Gm-Message-State: AGi0PuYNggmM6by0DG4KG9bLr7X//hhqN4HvtcbLZQ4sp7yWBHqEiLCa z/ZCmryJ2Gz6AhKGv/MRcIfyvw== X-Google-Smtp-Source: APiQypL0jJAGP0KYiq4xc4nfkEj6Ve2H6MRdFYIgYzUTD/bPjtmfpTZVeXWK4n9dyWmezbWFwHJWVQ== X-Received: by 2002:a63:9143:: with SMTP id l64mr388752pge.75.1586197538998; Mon, 06 Apr 2020 11:25:38 -0700 (PDT) Received: from www.outflux.net (smtp.outflux.net. [198.145.64.163]) by smtp.gmail.com with ESMTPSA id 17sm1673185pfa.8.2020.04.06.11.25.37 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 06 Apr 2020 11:25:38 -0700 (PDT) Date: Mon, 6 Apr 2020 11:25:37 -0700 From: Kees Cook To: Sami Tolvanen Cc: Will Deacon , Catalin Marinas , James Morse , Steven Rostedt , Masami Hiramatsu , Ard Biesheuvel , Mark Rutland , Dave Martin , Laura Abbott , Marc Zyngier , Nick Desaulniers , Jann Horn , Miguel Ojeda , Masahiro Yamada , clang-built-linux@googlegroups.com, kernel-hardening@lists.openwall.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v10 12/12] efi/libstub: disable SCS Message-ID: <202004061125.A4C4EB70@keescook> References: <20191018161033.261971-1-samitolvanen@google.com> <20200406164121.154322-1-samitolvanen@google.com> <20200406164121.154322-13-samitolvanen@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200406164121.154322-13-samitolvanen@google.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Apr 06, 2020 at 09:41:21AM -0700, Sami Tolvanen wrote: > Shadow stacks are not available in the EFI stub, filter out SCS flags. > > Suggested-by: James Morse > Signed-off-by: Sami Tolvanen Reviewed-by: Kees Cook > --- > drivers/firmware/efi/libstub/Makefile | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/drivers/firmware/efi/libstub/Makefile b/drivers/firmware/efi/libstub/Makefile > index 094eabdecfe6..fa0bb64f93d6 100644 > --- a/drivers/firmware/efi/libstub/Makefile > +++ b/drivers/firmware/efi/libstub/Makefile > @@ -32,6 +32,9 @@ KBUILD_CFLAGS := $(cflags-y) -DDISABLE_BRANCH_PROFILING \ > $(call cc-option,-fno-stack-protector) \ > -D__DISABLE_EXPORTS > > +# remove SCS flags from all objects in this directory nit: double space -Kees > +KBUILD_CFLAGS := $(filter-out $(CC_FLAGS_SCS), $(KBUILD_CFLAGS)) > + > GCOV_PROFILE := n > KASAN_SANITIZE := n > UBSAN_SANITIZE := n > -- > 2.26.0.292.g33ef6b2f38-goog > -- Kees Cook