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=-11.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT 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 1A6ADC32753 for ; Wed, 14 Aug 2019 17:12:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E273221721 for ; Wed, 14 Aug 2019 17:12:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1565802754; bh=o4LAQK483Q6DdzmPzHeYVkEq9+wOBvdyI/oGyKuoIJg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=xo+AjB8WH/9gsN4qBngijTUvzxEWYYT3rJ0fNDtHM9f9jR8zbMo9AfR7r9y5DFdSf BwtNgNT004D6/7D0d4MWigtZmYkE5F3UEVXN/mZ2JZNouklgPBwpTpwctYfZuhUtMw 3QaE0n59Xhu+ZaRlB1+6w3ZJ47p6UWWPRFgPXmEo= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730752AbfHNRMc (ORCPT ); Wed, 14 Aug 2019 13:12:32 -0400 Received: from mail.kernel.org ([198.145.29.99]:36342 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730742AbfHNRMa (ORCPT ); Wed, 14 Aug 2019 13:12:30 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 6A70F2084D; Wed, 14 Aug 2019 17:12:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1565802748; bh=o4LAQK483Q6DdzmPzHeYVkEq9+wOBvdyI/oGyKuoIJg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=oWuKlmy9RfohKf+3JD3DRt5DHTmffDBXcMISNjuR2fF+95foCsnGai3xMO7RPpe6p mnWYx8GzL56KdOMuNz3t9CUdId/ALExLSiTJtAWU6XGIIPDCTODSs852AaR9b3u3Jf YHhrYeMjgiR6uZtca6SfHLEHcsfyqS0OrXj8OwD0= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Nathan Chancellor , Alan Modra , Jordan Rupprect , Kees Cook , Nick Desaulniers Subject: [PATCH 4.14 11/69] lkdtm: support llvm-objcopy Date: Wed, 14 Aug 2019 19:01:09 +0200 Message-Id: <20190814165746.249357318@linuxfoundation.org> X-Mailer: git-send-email 2.22.0 In-Reply-To: <20190814165744.822314328@linuxfoundation.org> References: <20190814165744.822314328@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Nick Desaulniers commit e9e08a07385e08f1a7f85c5d1e345c21c9564963 upstream. With CONFIG_LKDTM=y and make OBJCOPY=llvm-objcopy, llvm-objcopy errors: llvm-objcopy: error: --set-section-flags=.text conflicts with --rename-section=.text=.rodata Rather than support setting flags then renaming sections vs renaming then setting flags, it's simpler to just change both at the same time via --rename-section. Adding the load flag is required for GNU objcopy to mark .rodata Type as PROGBITS after the rename. This can be verified with: $ readelf -S drivers/misc/lkdtm/rodata_objcopy.o ... Section Headers: [Nr] Name Type Address Offset Size EntSize Flags Link Info Align ... [ 1] .rodata PROGBITS 0000000000000000 00000040 0000000000000004 0000000000000000 A 0 0 4 ... Which shows that .text is now renamed .rodata, the alloc flag A is set, the type is PROGBITS, and the section is not flagged as writeable W. Cc: stable@vger.kernel.org Link: https://sourceware.org/bugzilla/show_bug.cgi?id=24554 Link: https://github.com/ClangBuiltLinux/linux/issues/448 Reported-by: Nathan Chancellor Suggested-by: Alan Modra Suggested-by: Jordan Rupprect Suggested-by: Kees Cook Acked-by: Kees Cook Reviewed-by: Nathan Chancellor Signed-off-by: Nick Desaulniers Signed-off-by: Greg Kroah-Hartman commit e9e08a07385e08f1a7f85c5d1e345c21c9564963 upstream. With CONFIG_LKDTM=y and make OBJCOPY=llvm-objcopy, llvm-objcopy errors: llvm-objcopy: error: --set-section-flags=.text conflicts with --rename-section=.text=.rodata Rather than support setting flags then renaming sections vs renaming then setting flags, it's simpler to just change both at the same time via --rename-section. Adding the load flag is required for GNU objcopy to mark .rodata Type as PROGBITS after the rename. This can be verified with: $ readelf -S drivers/misc/lkdtm/rodata_objcopy.o ... Section Headers: [Nr] Name Type Address Offset Size EntSize Flags Link Info Align ... [ 1] .rodata PROGBITS 0000000000000000 00000040 0000000000000004 0000000000000000 A 0 0 4 ... Which shows that .text is now renamed .rodata, the alloc flag A is set, the type is PROGBITS, and the section is not flagged as writeable W. Cc: stable@vger.kernel.org Link: https://sourceware.org/bugzilla/show_bug.cgi?id=24554 Link: https://github.com/ClangBuiltLinux/linux/issues/448 Reported-by: Nathan Chancellor Suggested-by: Alan Modra Suggested-by: Jordan Rupprect Suggested-by: Kees Cook Acked-by: Kees Cook Reviewed-by: Nathan Chancellor Signed-off-by: Nick Desaulniers Signed-off-by: Greg Kroah-Hartman --- drivers/misc/Makefile | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) --- a/drivers/misc/Makefile +++ b/drivers/misc/Makefile @@ -69,8 +69,7 @@ KCOV_INSTRUMENT_lkdtm_rodata.o := n OBJCOPYFLAGS := OBJCOPYFLAGS_lkdtm_rodata_objcopy.o := \ - --set-section-flags .text=alloc,readonly \ - --rename-section .text=.rodata + --rename-section .text=.rodata,alloc,readonly,load targets += lkdtm_rodata.o lkdtm_rodata_objcopy.o $(obj)/lkdtm_rodata_objcopy.o: $(obj)/lkdtm_rodata.o FORCE $(call if_changed,objcopy)