From nobody Fri Apr 10 14:02:22 2026 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 58004ECDFA1 for ; Tue, 25 Oct 2022 14:13:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233083AbiJYONu (ORCPT ); Tue, 25 Oct 2022 10:13:50 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46194 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233016AbiJYONo (ORCPT ); Tue, 25 Oct 2022 10:13:44 -0400 Received: from mail.ispras.ru (mail.ispras.ru [83.149.199.84]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C2994A98CD; Tue, 25 Oct 2022 07:13:33 -0700 (PDT) Received: from localhost.localdomain (unknown [83.149.199.65]) by mail.ispras.ru (Postfix) with ESMTPSA id 36DDE419E9F8; Tue, 25 Oct 2022 14:13:32 +0000 (UTC) DKIM-Filter: OpenDKIM Filter v2.11.0 mail.ispras.ru 36DDE419E9F8 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ispras.ru; s=default; t=1666707212; bh=4eVW1eJcsrjHfvua5xgjsd3gl1WJesFtv8uJ2bacg94=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=rBX76ErHdSBb9NvE24qugxdvfpl7OBObs2qpDC0JnIVm51/gGJdWGo8Q/JjnoRaMX fE1trKCitrGKWOyf6shizWHYbhJ7wrPMXgayRDhfyckm3NgtA8pEZT3n79LeHSLeh4 Qi8FMOclBpW78F8oMS9KJEKrSvasr2T0HQrRDr7k= 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 , lvc-project@linuxtesting.org, x86@kernel.org, linux-efi@vger.kernel.org, linux-kernel@vger.kernel.org, linux-hardening@vger.kernel.org Subject: [PATCH v2 07/23] x86/build: Check W^X of vmlinux during build Date: Tue, 25 Oct 2022 17:12:45 +0300 Message-Id: <84186fd75772b89be1984d6da0764a65cdef0c29.1666705333.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. 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 3a261abb6d15..64de6c2b1740 100644 --- a/arch/x86/boot/compressed/Makefile +++ b/arch/x86/boot/compressed/Makefile @@ -112,11 +112,17 @@ vmlinux-objs-$(CONFIG_EFI_MIXED) +=3D $(obj)/efi_thun= k_$(BITS).o vmlinux-objs-$(CONFIG_EFI) +=3D $(obj)/efi.o efi-obj-$(CONFIG_EFI_STUB) =3D $(objtree)/drivers/firmware/efi/libstub/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) $(efi-obj-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