From patchwork Wed Jun 24 01:49:37 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kees Cook X-Patchwork-Id: 11622207 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id BDE6192A for ; Wed, 24 Jun 2020 01:52:17 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 966BF20702 for ; Wed, 24 Jun 2020 01:52:17 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="Q0yU3Qf1"; dkim=fail reason="signature verification failed" (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="HU0okjxi" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 966BF20702 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=chromium.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To:Message-Id:Date: Subject:To:From:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=nohSTCmM6uME5V+hVeTtx+eBYiykTR7fa4XFCz2ke4I=; b=Q0yU3Qf12Y2h/+OXRUknrs0Xn RnY6wfsEoCFkjJD1bSEeWn4jWfZnvaGsN4tqCauupgVxaWSPpFxiBv1YvAu/KiowGukVKNkltHoHX GYuPXAk946Ye8LaNMb0G3KZXwsBdNUHXWV4vyagAIvIZSiLEkPS9tAoNdzzHAGeZXtAygWyUypZ65 2akG20vb6bNVWm9w7+TN3I7YocLLxELdhgdNmH0M/VXiwzPqvpilEZwGWE9uQ7tgUUP7ESTK37nwE TE6JDMxIiFyPCY4QKIeaxBhOioPrJs/dEOtvmuOgSczXyE+Wrop6i3qsnCxFdcTZBSnHnlMYdi0Fc ZLVNZ5OPw==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1jnuYZ-0006gb-VX; Wed, 24 Jun 2020 01:50:32 +0000 Received: from mail-pl1-x643.google.com ([2607:f8b0:4864:20::643]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1jnuXy-0006MO-8n for linux-arm-kernel@lists.infradead.org; Wed, 24 Jun 2020 01:49:59 +0000 Received: by mail-pl1-x643.google.com with SMTP id s14so332507plq.6 for ; Tue, 23 Jun 2020 18:49:53 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=l5ovQdOa53Wq08SUrbeqBNAB7olZAVfsR3FjDV/m7eY=; b=HU0okjxiFMvFctCffkQ7z2I5GXmLT1gaNRYMQRFcgYl5tSYJfuUMDlXvZKj80rjKKa yDPcFEuDuT1buIkUcXQlmVdjIfloGs7ZqN0zimqyc3ma6N3SZKtRnjISbLa1WJUqrcLr i29IZiC5pQBaTbC59gJVAGqy18hz7C2vTrLUU= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=l5ovQdOa53Wq08SUrbeqBNAB7olZAVfsR3FjDV/m7eY=; b=oljrlg5pxUmNXMQESe5zDagUfcP8KRQO8UzURcUUmAwKBkCHgRhYnMYnUd+ebfLYcR I4KPL09JlpgkynRXkLMINUXaxSZIvjXjhRlyDN1uUu+L3wg9i/yk+Dq/MZP65pJ2Yq5f JRtzLuJmTe6+Y+y7k9X8UVxuiOzB8/hRgILUBW2Lxsq6aYmnnGkghzqG4RECT6q41zr8 toTmVmGOjDfl1K7YfmOa2x3Kowj/dIgAU95SIvDjYa5dXJXVr61mu9kRM8/l5C6IKRsn sagTZjXE30tq1YgThPIaxD3AhbK6mLaEbpCAUbUNFjF/K31baRIQgPlRqTIvCS3I22NH WHzw== X-Gm-Message-State: AOAM5327/oyEOb6mo6kkQgLiiHE1uEhBizOXBkPrapB0r/EFElnJbJ+R OF0a/KAu58oA/9wM/3TQcNK5Xg== X-Google-Smtp-Source: ABdhPJwzVxoBS+bR4nUcdi2cBNUW1MxtFXQkch5ct6ivADYFpQcNz0i+34vFO2Sqx+gzfU7fOMW1Zg== X-Received: by 2002:a17:902:b184:: with SMTP id s4mr26340353plr.148.1592963392122; Tue, 23 Jun 2020 18:49:52 -0700 (PDT) Received: from www.outflux.net (smtp.outflux.net. [198.145.64.163]) by smtp.gmail.com with ESMTPSA id 25sm18020100pfi.7.2020.06.23.18.49.48 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 23 Jun 2020 18:49:50 -0700 (PDT) From: Kees Cook To: Will Deacon Subject: [PATCH v3 6/9] arm/build: Warn on orphan section placement Date: Tue, 23 Jun 2020 18:49:37 -0700 Message-Id: <20200624014940.1204448-7-keescook@chromium.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200624014940.1204448-1-keescook@chromium.org> References: <20200624014940.1204448-1-keescook@chromium.org> MIME-Version: 1.0 X-Spam-Note: CRM114 invocation failed X-Spam-Score: -0.2 (/) X-Spam-Report: SpamAssassin version 3.4.4 on merlin.infradead.org summary: Content analysis details: (-0.2 points) pts rule name description ---- ---------------------- -------------------------------------------------- -0.0 RCVD_IN_DNSWL_NONE RBL: Sender listed at https://www.dnswl.org/, no trust [2607:f8b0:4864:20:0:0:0:643 listed in] [list.dnswl.org] -0.0 SPF_PASS SPF: sender matches SPF record 0.0 SPF_HELO_NONE SPF: HELO does not publish an SPF Record 0.1 DKIM_SIGNED Message has a DKIM or DK signature, not necessarily valid -0.1 DKIM_VALID Message has at least one valid DKIM or DK signature -0.1 DKIM_VALID_AU Message has a valid DKIM or DK signature from author's domain -0.1 DKIM_VALID_EF Message has a valid DKIM or DK signature from envelope-from domain -0.0 DKIMWL_WL_HIGH DKIMwl.org - Whitelisted High sender X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Mark Rutland , linux-arch@vger.kernel.org, linux-efi@vger.kernel.org, Kees Cook , Arnd Bergmann , Catalin Marinas , Masahiro Yamada , x86@kernel.org, Nick Desaulniers , Russell King , linux-kernel@vger.kernel.org, Nathan Chancellor , clang-built-linux@googlegroups.com, Arvind Sankar , Ingo Molnar , James Morse , Thomas Gleixner , Borislav Petkov , Peter Collingbourne , Ard Biesheuvel , linux-arm-kernel@lists.infradead.org Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org We don't want to depend on the linker's orphan section placement heuristics as these can vary between linkers, and may change between versions. All sections need to be explicitly named in the linker script. Specifically, this would have made a recently fixed bug very obvious: ld: warning: orphan section `.fixup' from `arch/arm/lib/copy_from_user.o' being placed in section `.fixup' Refactor linker script include file for use in standard and XIP linker scripts, as well as in the coming boot linker script changes. Add debug sections explicitly. Create ARM_COMMON_DISCARD macro with unneeded sections .ARM.attributes, .iplt, .rel.iplt, .igot.plt, and .modinfo. Create ARM_STUBS_TEXT macro with missed text stub sections .vfp11_veneer, and .v4_bx. Finally enable orphan section warning. Signed-off-by: Kees Cook --- arch/arm/Makefile | 4 ++++ .../arm/{kernel => include/asm}/vmlinux.lds.h | 22 ++++++++++++++----- arch/arm/kernel/vmlinux-xip.lds.S | 5 ++--- arch/arm/kernel/vmlinux.lds.S | 5 ++--- 4 files changed, 25 insertions(+), 11 deletions(-) rename arch/arm/{kernel => include/asm}/vmlinux.lds.h (92%) diff --git a/arch/arm/Makefile b/arch/arm/Makefile index 59fde2d598d8..e414e3732b3a 100644 --- a/arch/arm/Makefile +++ b/arch/arm/Makefile @@ -16,6 +16,10 @@ LDFLAGS_vmlinux += --be8 KBUILD_LDFLAGS_MODULE += --be8 endif +# We never want expected sections to be placed heuristically by the +# linker. All sections should be explicitly named in the linker script. +LDFLAGS_vmlinux += --orphan-handling=warn + ifeq ($(CONFIG_ARM_MODULE_PLTS),y) KBUILD_LDS_MODULE += $(srctree)/arch/arm/kernel/module.lds endif diff --git a/arch/arm/kernel/vmlinux.lds.h b/arch/arm/include/asm/vmlinux.lds.h similarity index 92% rename from arch/arm/kernel/vmlinux.lds.h rename to arch/arm/include/asm/vmlinux.lds.h index 381a8e105fa5..3d88ea74f4cd 100644 --- a/arch/arm/kernel/vmlinux.lds.h +++ b/arch/arm/include/asm/vmlinux.lds.h @@ -1,4 +1,5 @@ /* SPDX-License-Identifier: GPL-2.0 */ +#include #ifdef CONFIG_HOTPLUG_CPU #define ARM_CPU_DISCARD(x) @@ -37,6 +38,13 @@ *(.idmap.text) \ __idmap_text_end = .; \ +#define ARM_COMMON_DISCARD \ + *(.ARM.attributes) \ + *(.iplt) *(.rel.iplt) *(.igot.plt) \ + *(.modinfo) \ + *(.discard) \ + *(.discard.*) + #define ARM_DISCARD \ *(.ARM.exidx.exit.text) \ *(.ARM.extab.exit.text) \ @@ -49,8 +57,14 @@ EXIT_CALL \ ARM_MMU_DISCARD(*(.text.fixup)) \ ARM_MMU_DISCARD(*(__ex_table)) \ - *(.discard) \ - *(.discard.*) + ARM_COMMON_DISCARD + +#define ARM_STUBS_TEXT \ + *(.gnu.warning) \ + *(.glue_7t) \ + *(.glue_7) \ + *(.vfp11_veneer) \ + *(.v4_bx) #define ARM_TEXT \ IDMAP_TEXT \ @@ -64,9 +78,7 @@ CPUIDLE_TEXT \ LOCK_TEXT \ KPROBES_TEXT \ - *(.gnu.warning) \ - *(.glue_7) \ - *(.glue_7t) \ + ARM_STUBS_TEXT \ . = ALIGN(4); \ *(.got) /* Global offset table */ \ ARM_CPU_KEEP(PROC_INFO) diff --git a/arch/arm/kernel/vmlinux-xip.lds.S b/arch/arm/kernel/vmlinux-xip.lds.S index 6d2be994ae58..0807f40844a2 100644 --- a/arch/arm/kernel/vmlinux-xip.lds.S +++ b/arch/arm/kernel/vmlinux-xip.lds.S @@ -9,15 +9,13 @@ #include -#include +#include #include #include #include #include #include -#include "vmlinux.lds.h" - OUTPUT_ARCH(arm) ENTRY(stext) @@ -152,6 +150,7 @@ SECTIONS _end = .; STABS_DEBUG + DWARF_DEBUG } /* diff --git a/arch/arm/kernel/vmlinux.lds.S b/arch/arm/kernel/vmlinux.lds.S index 7f24bc08403e..969205f125ca 100644 --- a/arch/arm/kernel/vmlinux.lds.S +++ b/arch/arm/kernel/vmlinux.lds.S @@ -9,15 +9,13 @@ #else #include -#include +#include #include #include #include #include #include -#include "vmlinux.lds.h" - OUTPUT_ARCH(arm) ENTRY(stext) @@ -151,6 +149,7 @@ SECTIONS _end = .; STABS_DEBUG + DWARF_DEBUG } #ifdef CONFIG_STRICT_KERNEL_RWX