From nobody Wed Sep 17 22:39:31 2025 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 5F13EC4167B for ; Thu, 15 Dec 2022 12:39:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230017AbiLOMjQ (ORCPT ); Thu, 15 Dec 2022 07:39:16 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53460 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229863AbiLOMiq (ORCPT ); Thu, 15 Dec 2022 07:38:46 -0500 Received: from mail.ispras.ru (mail.ispras.ru [83.149.199.84]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 332362F007; Thu, 15 Dec 2022 04:38:29 -0800 (PST) Received: from localhost.localdomain (unknown [83.149.199.65]) by mail.ispras.ru (Postfix) with ESMTPSA id BDB8F40737AF; Thu, 15 Dec 2022 12:38:22 +0000 (UTC) DKIM-Filter: OpenDKIM Filter v2.11.0 mail.ispras.ru BDB8F40737AF DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ispras.ru; s=default; t=1671107902; bh=aytHXLPe5WFTxHpmffbYFL3H8M/KUu6PP4gNt7AoPJg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=cDcOgTU86qfkkn+GkGXQbTgcmNdsXr3SsKorZvfOGrPtndS75vMdtsk/bvB1QJW0Y T2KXVmJJay7h8hUyXr7tTDtj1syOzP6X9Yp+MDvxEUr+/sY+5PUSO/g0hKwV0XM17g BeYkQvie4yzPmMvIeTjfXjikHG6Ry6iRRfX/3bxw= 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 v4 07/26] x86/build: Check W^X of vmlinux during build Date: Thu, 15 Dec 2022 15:37:58 +0300 Message-Id: <3ca525852ce14a8e04949ff115cb6ec28c8f120b.1671098103.git.baskov@ispras.ru> X-Mailer: git-send-email 2.37.4 In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" 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 Tested-by: Peter Jones 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/M= akefile index 1acff356d97a..4dcab38f5a38 100644 --- a/arch/x86/boot/compressed/Makefile +++ b/arch/x86/boot/compressed/Makefile @@ -112,11 +112,17 @@ vmlinux-objs-$(CONFIG_EFI) +=3D $(obj)/efi.o vmlinux-objs-$(CONFIG_EFI_MIXED) +=3D $(obj)/efi_mixed.o vmlinux-objs-$(CONFIG_EFI_STUB) +=3D $(objtree)/drivers/firmware/efi/libst= ub/lib.a =20 +quiet_cmd_wx_check =3D WXCHK $< +cmd_wx_check =3D if $(OBJDUMP) -p $< | grep "flags .wx" > /dev/null; \ + then (echo >&2 "$<: Simultaneously writable and executable section= s are prohibited"; \ + /bin/false); fi + $(obj)/vmlinux: $(vmlinux-objs-y) FORCE $(call if_changed,ld) =20 OBJCOPYFLAGS_vmlinux.bin :=3D -R .comment -S $(obj)/vmlinux.bin: vmlinux FORCE + $(call cmd,wx_check) $(call if_changed,objcopy) =20 targets +=3D $(patsubst $(obj)/%,%,$(vmlinux-objs-y)) vmlinux.bin.all vmli= nux.relocs --=20 2.37.4