From mboxrd@z Thu Jan 1 00:00:00 1970 From: Kees Cook Subject: [PATCH v5 04/36] x86/boot: Add .text.* to setup.ld Date: Fri, 31 Jul 2020 16:07:48 -0700 Message-ID: <20200731230820.1742553-5-keescook@chromium.org> References: <20200731230820.1742553-1-keescook@chromium.org> Mime-Version: 1.0 Content-Transfer-Encoding: 8bit Return-path: In-Reply-To: <20200731230820.1742553-1-keescook@chromium.org> Sender: linux-kernel-owner@vger.kernel.org To: Thomas Gleixner , Will Deacon Cc: Kees Cook , Arvind Sankar , Nick Desaulniers , Ard Biesheuvel , Fangrui Song , Sedat Dilek , Catalin Marinas , Mark Rutland , Peter Collingbourne , James Morse , Borislav Petkov , Ingo Molnar , Russell King , Masahiro Yamada , Nathan Chancellor , Arnd Bergmann , x86@kernel.org, clang-built-linux@googlegroups.com, linux-arch@vger.kernel.org, linux-efi@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.ker List-Id: linux-arch.vger.kernel.org From: Arvind Sankar gcc puts the main function into .text.startup when compiled with -Os (or -O2). This results in arch/x86/boot/main.c having a .text.startup section which is currently not included explicitly in the linker script setup.ld in the same directory. The BFD linker places this orphan section immediately after .text, so this still works. However, LLD git, since [1], is choosing to place it immediately after the .bstext section instead (this is the first code section). This plays havoc with the section layout that setup.elf requires to create the setup header, for eg on 64-bit: LD arch/x86/boot/setup.elf ld.lld: error: section .text.startup file range overlaps with .header >>> .text.startup range is [0x200040, 0x2001FE] >>> .header range is [0x2001EF, 0x20026B] ld.lld: error: section .header file range overlaps with .bsdata >>> .header range is [0x2001EF, 0x20026B] >>> .bsdata range is [0x2001FF, 0x200398] ld.lld: error: section .bsdata file range overlaps with .entrytext >>> .bsdata range is [0x2001FF, 0x200398] >>> .entrytext range is [0x20026C, 0x2002D3] ld.lld: error: section .text.startup virtual address range overlaps with .header >>> .text.startup range is [0x40, 0x1FE] >>> .header range is [0x1EF, 0x26B] ld.lld: error: section .header virtual address range overlaps with .bsdata >>> .header range is [0x1EF, 0x26B] >>> .bsdata range is [0x1FF, 0x398] ld.lld: error: section .bsdata virtual address range overlaps with .entrytext >>> .bsdata range is [0x1FF, 0x398] >>> .entrytext range is [0x26C, 0x2D3] ld.lld: error: section .text.startup load address range overlaps with .header >>> .text.startup range is [0x40, 0x1FE] >>> .header range is [0x1EF, 0x26B] ld.lld: error: section .header load address range overlaps with .bsdata >>> .header range is [0x1EF, 0x26B] >>> .bsdata range is [0x1FF, 0x398] ld.lld: error: section .bsdata load address range overlaps with .entrytext >>> .bsdata range is [0x1FF, 0x398] >>> .entrytext range is [0x26C, 0x2D3] Add .text.* to the .text output section to fix this, and also prevent any future surprises if the compiler decides to create other such sections. [1] https://reviews.llvm.org/D75225 Tested-by: Nick Desaulniers Reviewed-by: Kees Cook Reviewed-by: Ard Biesheuvel Reviewed-by: Fangrui Song Tested-by: Sedat Dilek Signed-off-by: Arvind Sankar Signed-off-by: Kees Cook --- arch/x86/boot/setup.ld | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/boot/setup.ld b/arch/x86/boot/setup.ld index 24c95522f231..49546c247ae2 100644 --- a/arch/x86/boot/setup.ld +++ b/arch/x86/boot/setup.ld @@ -20,7 +20,7 @@ SECTIONS .initdata : { *(.initdata) } __end_init = .; - .text : { *(.text) } + .text : { *(.text .text.*) } .text32 : { *(.text32) } . = ALIGN(16); -- 2.25.1 From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45726 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726347AbgGaXIc (ORCPT ); Fri, 31 Jul 2020 19:08:32 -0400 Received: from mail-pf1-x444.google.com (mail-pf1-x444.google.com [IPv6:2607:f8b0:4864:20::444]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 65C4EC061757 for ; Fri, 31 Jul 2020 16:08:32 -0700 (PDT) Received: by mail-pf1-x444.google.com with SMTP id l2so8848216pff.0 for ; Fri, 31 Jul 2020 16:08:32 -0700 (PDT) From: Kees Cook Subject: [PATCH v5 04/36] x86/boot: Add .text.* to setup.ld Date: Fri, 31 Jul 2020 16:07:48 -0700 Message-ID: <20200731230820.1742553-5-keescook@chromium.org> In-Reply-To: <20200731230820.1742553-1-keescook@chromium.org> References: <20200731230820.1742553-1-keescook@chromium.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-arch-owner@vger.kernel.org List-ID: To: Thomas Gleixner , Will Deacon Cc: Kees Cook , Arvind Sankar , Nick Desaulniers , Ard Biesheuvel , Fangrui Song , Sedat Dilek , Catalin Marinas , Mark Rutland , Peter Collingbourne , James Morse , Borislav Petkov , Ingo Molnar , Russell King , Masahiro Yamada , Nathan Chancellor , Arnd Bergmann , x86@kernel.org, clang-built-linux@googlegroups.com, linux-arch@vger.kernel.org, linux-efi@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Message-ID: <20200731230748.QbsiKj8ji-0BblQr7aQdjO9GZeaENZQ9blQEtw_Hlp0@z> From: Arvind Sankar gcc puts the main function into .text.startup when compiled with -Os (or -O2). This results in arch/x86/boot/main.c having a .text.startup section which is currently not included explicitly in the linker script setup.ld in the same directory. The BFD linker places this orphan section immediately after .text, so this still works. However, LLD git, since [1], is choosing to place it immediately after the .bstext section instead (this is the first code section). This plays havoc with the section layout that setup.elf requires to create the setup header, for eg on 64-bit: LD arch/x86/boot/setup.elf ld.lld: error: section .text.startup file range overlaps with .header >>> .text.startup range is [0x200040, 0x2001FE] >>> .header range is [0x2001EF, 0x20026B] ld.lld: error: section .header file range overlaps with .bsdata >>> .header range is [0x2001EF, 0x20026B] >>> .bsdata range is [0x2001FF, 0x200398] ld.lld: error: section .bsdata file range overlaps with .entrytext >>> .bsdata range is [0x2001FF, 0x200398] >>> .entrytext range is [0x20026C, 0x2002D3] ld.lld: error: section .text.startup virtual address range overlaps with .header >>> .text.startup range is [0x40, 0x1FE] >>> .header range is [0x1EF, 0x26B] ld.lld: error: section .header virtual address range overlaps with .bsdata >>> .header range is [0x1EF, 0x26B] >>> .bsdata range is [0x1FF, 0x398] ld.lld: error: section .bsdata virtual address range overlaps with .entrytext >>> .bsdata range is [0x1FF, 0x398] >>> .entrytext range is [0x26C, 0x2D3] ld.lld: error: section .text.startup load address range overlaps with .header >>> .text.startup range is [0x40, 0x1FE] >>> .header range is [0x1EF, 0x26B] ld.lld: error: section .header load address range overlaps with .bsdata >>> .header range is [0x1EF, 0x26B] >>> .bsdata range is [0x1FF, 0x398] ld.lld: error: section .bsdata load address range overlaps with .entrytext >>> .bsdata range is [0x1FF, 0x398] >>> .entrytext range is [0x26C, 0x2D3] Add .text.* to the .text output section to fix this, and also prevent any future surprises if the compiler decides to create other such sections. [1] https://reviews.llvm.org/D75225 Tested-by: Nick Desaulniers Reviewed-by: Kees Cook Reviewed-by: Ard Biesheuvel Reviewed-by: Fangrui Song Tested-by: Sedat Dilek Signed-off-by: Arvind Sankar Signed-off-by: Kees Cook --- arch/x86/boot/setup.ld | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/boot/setup.ld b/arch/x86/boot/setup.ld index 24c95522f231..49546c247ae2 100644 --- a/arch/x86/boot/setup.ld +++ b/arch/x86/boot/setup.ld @@ -20,7 +20,7 @@ SECTIONS .initdata : { *(.initdata) } __end_init = .; - .text : { *(.text) } + .text : { *(.text .text.*) } .text32 : { *(.text32) } . = ALIGN(16); -- 2.25.1