From patchwork Tue Nov 22 11:12:16 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Evgeniy Baskov X-Patchwork-Id: 13052202 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 96449C4321E for ; Tue, 22 Nov 2022 11:13:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231318AbiKVLM7 (ORCPT ); Tue, 22 Nov 2022 06:12:59 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58972 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233013AbiKVLMt (ORCPT ); Tue, 22 Nov 2022 06:12:49 -0500 Received: from mail.ispras.ru (mail.ispras.ru [83.149.199.84]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2F354A4; Tue, 22 Nov 2022 03:12:48 -0800 (PST) Received: from localhost.localdomain (unknown [83.149.199.65]) by mail.ispras.ru (Postfix) with ESMTPSA id 0491940737C3; Tue, 22 Nov 2022 11:12:42 +0000 (UTC) DKIM-Filter: OpenDKIM Filter v2.11.0 mail.ispras.ru 0491940737C3 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ispras.ru; s=default; t=1669115562; bh=zJyjXdeGncN0/sCqkQ6LWnTu+HAOR00PivwRmGI/62E=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=XOkIZdYOveVvoUdyG5wJ1ub0mdhP43FQ/wnUmCYA90XpAOfHLev5q4XWjd+mmHXnX RvZZEsePoUe5/5lNRDYmdrM0J2lSA2lqxwSv0C5tolDpC9/FjmGGXfpF1KrlTUUqh/ XXcfH0sglQeGoz6jxe4vQk2uu/eZ6L8XQG+M+5PM= From: Evgeniy Baskov To: Ard Biesheuvel Cc: Evgeniy Baskov , Borislav Petkov , Andy Lutomirski , Dave Hansen , Ingo Molnar , Peter Zijlstra , Thomas Gleixner , Alexey Khoroshilov , Peter Jones , "Limonciello, Mario" , joeyli , lvc-project@linuxtesting.org, x86@kernel.org, linux-efi@vger.kernel.org, linux-kernel@vger.kernel.org, linux-hardening@vger.kernel.org Subject: [PATCH v3 07/24] x86/build: Check W^X of vmlinux during build Date: Tue, 22 Nov 2022 14:12:16 +0300 Message-Id: <686f40eb9c83f9b5e4deba7bfb6cc9c0626d310c.1668958803.git.baskov@ispras.ru> X-Mailer: git-send-email 2.37.4 In-Reply-To: References: MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-hardening@vger.kernel.org Check if there are simultaneously writable and executable program segments in vmlinux ELF image and fail build if there are any. This would prevent accidental introduction of RWX segments. Tested-by: Mario Limonciello Signed-off-by: Evgeniy Baskov --- arch/x86/boot/compressed/Makefile | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/arch/x86/boot/compressed/Makefile b/arch/x86/boot/compressed/Makefile index 3a261abb6d15..64de6c2b1740 100644 --- a/arch/x86/boot/compressed/Makefile +++ b/arch/x86/boot/compressed/Makefile @@ -112,11 +112,17 @@ vmlinux-objs-$(CONFIG_EFI_MIXED) += $(obj)/efi_thunk_$(BITS).o vmlinux-objs-$(CONFIG_EFI) += $(obj)/efi.o efi-obj-$(CONFIG_EFI_STUB) = $(objtree)/drivers/firmware/efi/libstub/lib.a +quiet_cmd_wx_check = WXCHK $< +cmd_wx_check = if $(OBJDUMP) -p $< | grep "flags .wx" > /dev/null; \ + then (echo >&2 "$<: Simultaneously writable and executable sections are prohibited"; \ + /bin/false); fi + $(obj)/vmlinux: $(vmlinux-objs-y) $(efi-obj-y) FORCE $(call if_changed,ld) OBJCOPYFLAGS_vmlinux.bin := -R .comment -S $(obj)/vmlinux.bin: vmlinux FORCE + $(call cmd,wx_check) $(call if_changed,objcopy) targets += $(patsubst $(obj)/%,%,$(vmlinux-objs-y)) vmlinux.bin.all vmlinux.relocs