From patchwork Tue Oct 13 00:31:39 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sami Tolvanen X-Patchwork-Id: 11834547 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 EABAA92C for ; Tue, 13 Oct 2020 00:32:28 +0000 (UTC) Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.kernel.org (Postfix) with SMTP id DA59F21655 for ; Tue, 13 Oct 2020 00:32:27 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="Z96hT5gh" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org DA59F21655 Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kernel-hardening-return-20174-patchwork-kernel-hardening=patchwork.kernel.org@lists.openwall.com Received: (qmail 10051 invoked by uid 550); 13 Oct 2020 00:32:20 -0000 Mailing-List: contact kernel-hardening-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Delivered-To: mailing list kernel-hardening@lists.openwall.com Received: (qmail 9881 invoked from network); 13 Oct 2020 00:32:19 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=sender:date:in-reply-to:message-id:mime-version:references:subject :from:to:cc; bh=cloCclz36A1w92k6Zbeecg4QRyayzvUWthNVuds2M9U=; b=Z96hT5ghe95A4l04B5UCnPDxXSIMybdadUy/cjvfyIfXj6wxTXzuWH2I8ouvwAYXQj LBOhLRSvRP2iNbCnrzvy9iCC1A1QBU/BWo5ItmOegPJ5Bxskm6xzbsvJCCQbvRaapvNT yKM6gqIiKsmifZbaWj0xem9mLLHq+XOv8S9d6pjnZp0Rwwtj1WnmshYxVOVxmOU9Xth6 +86qF78YZLlLF1Ytnb3a4FYnrd6rvIkNRGsewv1ZIfz83z1DnjDHho2xRkKGjVHwheNz kFakYaKKt70pSbEcht4vngbZjDv3FXiG54n8U0UYJkrP1KqAwYwBFchuQ4Tz0rdhM3nl 8nog== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=cloCclz36A1w92k6Zbeecg4QRyayzvUWthNVuds2M9U=; b=YEaGVsc2h+K+JJCg8pHXKRYqa6+yRCwiD9PKQZlH1hgPR6xRAsxidD4CK+BrN5EFkK aN1xncT9g21yLSYUiRbqgByqfEfkYTx7p23myV5QFolUZ7r+Kow5IHt908OWzx0U0e7Q AbfTtvrGYJ6a4kc0Bp2Fo+6HICakWTPRzaT8bIXd80n0v+pqaxAp2Yn3qqFGDDBkGGLM 1lSRDgXAOf8wsBPaZCbYw5E+FDVQRZg0caKoRr3Yyv7f40V/4Ije/wP90EI1EUdUm1mN m+bK+gF87UkKbhTE9gHcadWihQ+9J7Oiwvn0GpwZOaHqI2DWpy9PxIZtJBAc/bono8+y 3tHQ== X-Gm-Message-State: AOAM530SZU+ffx28uBPmjuiMnK1fMHM/esWyEAno3rDy1PwadaX/ljXM VlaUmkkaE0Tnu4PZA/CAEyFdm7Eg6sQT+KDD5IU= X-Google-Smtp-Source: ABdhPJwkNyv1MD6cWxznbV/DuOICSJnW/qGDGOQmA0l8Q53uBj4VWtQnElrVm3rGF6TBes7M9vMjukgDrEXb9mO7Mws= Sender: "samitolvanen via sendgmr" X-Received: from samitolvanen1.mtv.corp.google.com ([2620:15c:201:2:f693:9fff:fef4:1b6d]) (user=samitolvanen job=sendgmr) by 2002:a25:5403:: with SMTP id i3mr40522422ybb.43.1602549127241; Mon, 12 Oct 2020 17:32:07 -0700 (PDT) Date: Mon, 12 Oct 2020 17:31:39 -0700 In-Reply-To: <20201013003203.4168817-1-samitolvanen@google.com> Message-Id: <20201013003203.4168817-2-samitolvanen@google.com> Mime-Version: 1.0 References: <20201013003203.4168817-1-samitolvanen@google.com> X-Mailer: git-send-email 2.28.0.1011.ga647a8990f-goog Subject: [PATCH v6 01/25] kbuild: preprocess module linker script From: Sami Tolvanen To: Masahiro Yamada , Steven Rostedt Cc: Will Deacon , Peter Zijlstra , Greg Kroah-Hartman , "Paul E. McKenney" , Kees Cook , Nick Desaulniers , clang-built-linux@googlegroups.com, kernel-hardening@lists.openwall.com, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, x86@kernel.org From: Masahiro Yamada There was a request to preprocess the module linker script like we do for the vmlinux one. (https://lkml.org/lkml/2020/8/21/512) The difference between vmlinux.lds and module.lds is that the latter is needed for external module builds, thus must be cleaned up by 'make mrproper' instead of 'make clean'. Also, it must be created by 'make modules_prepare'. You cannot put it in arch/$(SRCARCH)/kernel/, which is cleaned up by 'make clean'. I moved arch/$(SRCARCH)/kernel/module.lds to arch/$(SRCARCH)/include/asm/module.lds.h, which is included from scripts/module.lds.S. scripts/module.lds is fine because 'make clean' keeps all the build artifacts under scripts/. You can add arch-specific sections in . Signed-off-by: Masahiro Yamada Tested-by: Jessica Yu Acked-by: Will Deacon Acked-by: Geert Uytterhoeven Acked-by: Palmer Dabbelt Reviewed-by: Kees Cook Acked-by: Jessica Yu --- Makefile | 10 ++++++---- arch/arm/Makefile | 4 ---- .../{kernel/module.lds => include/asm/module.lds.h} | 2 ++ arch/arm64/Makefile | 4 ---- .../{kernel/module.lds => include/asm/module.lds.h} | 2 ++ arch/ia64/Makefile | 1 - arch/ia64/{module.lds => include/asm/module.lds.h} | 0 arch/m68k/Makefile | 1 - .../{kernel/module.lds => include/asm/module.lds.h} | 0 arch/powerpc/Makefile | 1 - .../{kernel/module.lds => include/asm/module.lds.h} | 0 arch/riscv/Makefile | 3 --- .../{kernel/module.lds => include/asm/module.lds.h} | 3 ++- arch/um/include/asm/Kbuild | 1 + include/asm-generic/Kbuild | 1 + include/asm-generic/module.lds.h | 10 ++++++++++ scripts/.gitignore | 1 + scripts/Makefile | 3 +++ scripts/Makefile.modfinal | 5 ++--- scripts/{module-common.lds => module.lds.S} | 3 +++ scripts/package/builddeb | 2 +- 21 files changed, 34 insertions(+), 23 deletions(-) rename arch/arm/{kernel/module.lds => include/asm/module.lds.h} (72%) rename arch/arm64/{kernel/module.lds => include/asm/module.lds.h} (76%) rename arch/ia64/{module.lds => include/asm/module.lds.h} (100%) rename arch/m68k/{kernel/module.lds => include/asm/module.lds.h} (100%) rename arch/powerpc/{kernel/module.lds => include/asm/module.lds.h} (100%) rename arch/riscv/{kernel/module.lds => include/asm/module.lds.h} (84%) create mode 100644 include/asm-generic/module.lds.h rename scripts/{module-common.lds => module.lds.S} (93%) diff --git a/Makefile b/Makefile index 51540b291738..0dcf302fe2da 100644 --- a/Makefile +++ b/Makefile @@ -505,7 +505,6 @@ KBUILD_CFLAGS_KERNEL := KBUILD_AFLAGS_MODULE := -DMODULE KBUILD_CFLAGS_MODULE := -DMODULE KBUILD_LDFLAGS_MODULE := -export KBUILD_LDS_MODULE := $(srctree)/scripts/module-common.lds KBUILD_LDFLAGS := CLANG_FLAGS := @@ -1384,7 +1383,7 @@ endif # using awk while concatenating to the final file. PHONY += modules -modules: $(if $(KBUILD_BUILTIN),vmlinux) modules_check +modules: $(if $(KBUILD_BUILTIN),vmlinux) modules_check modules_prepare $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost PHONY += modules_check @@ -1401,6 +1400,7 @@ targets += modules.order # Target to prepare building external modules PHONY += modules_prepare modules_prepare: prepare + $(Q)$(MAKE) $(build)=scripts scripts/module.lds # Target to install modules PHONY += modules_install @@ -1722,7 +1722,9 @@ help: @echo ' clean - remove generated files in module directory only' @echo '' -PHONY += prepare +# no-op for external module builds +PHONY += prepare modules_prepare + endif # KBUILD_EXTMOD # Single targets @@ -1755,7 +1757,7 @@ MODORDER := .modules.tmp endif PHONY += single_modpost -single_modpost: $(single-no-ko) +single_modpost: $(single-no-ko) modules_prepare $(Q){ $(foreach m, $(single-ko), echo $(extmod-prefix)$m;) } > $(MODORDER) $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost diff --git a/arch/arm/Makefile b/arch/arm/Makefile index e589da3c8949..9c4d19ae7d61 100644 --- a/arch/arm/Makefile +++ b/arch/arm/Makefile @@ -20,10 +20,6 @@ endif # linker. All sections should be explicitly named in the linker script. LDFLAGS_vmlinux += $(call ld-option, --orphan-handling=warn) -ifeq ($(CONFIG_ARM_MODULE_PLTS),y) -KBUILD_LDS_MODULE += $(srctree)/arch/arm/kernel/module.lds -endif - GZFLAGS :=-9 #KBUILD_CFLAGS +=-pipe diff --git a/arch/arm/kernel/module.lds b/arch/arm/include/asm/module.lds.h similarity index 72% rename from arch/arm/kernel/module.lds rename to arch/arm/include/asm/module.lds.h index 79cb6af565e5..0e7cb4e314b4 100644 --- a/arch/arm/kernel/module.lds +++ b/arch/arm/include/asm/module.lds.h @@ -1,5 +1,7 @@ /* SPDX-License-Identifier: GPL-2.0 */ +#ifdef CONFIG_ARM_MODULE_PLTS SECTIONS { .plt : { BYTE(0) } .init.plt : { BYTE(0) } } +#endif diff --git a/arch/arm64/Makefile b/arch/arm64/Makefile index aff994473eb2..32d7e07b0acf 100644 --- a/arch/arm64/Makefile +++ b/arch/arm64/Makefile @@ -127,10 +127,6 @@ endif CHECKFLAGS += -D__aarch64__ -ifeq ($(CONFIG_ARM64_MODULE_PLTS),y) -KBUILD_LDS_MODULE += $(srctree)/arch/arm64/kernel/module.lds -endif - ifeq ($(CONFIG_DYNAMIC_FTRACE_WITH_REGS),y) KBUILD_CPPFLAGS += -DCC_USING_PATCHABLE_FUNCTION_ENTRY CC_FLAGS_FTRACE := -fpatchable-function-entry=2 diff --git a/arch/arm64/kernel/module.lds b/arch/arm64/include/asm/module.lds.h similarity index 76% rename from arch/arm64/kernel/module.lds rename to arch/arm64/include/asm/module.lds.h index 22e36a21c113..691f15af788e 100644 --- a/arch/arm64/kernel/module.lds +++ b/arch/arm64/include/asm/module.lds.h @@ -1,5 +1,7 @@ +#ifdef CONFIG_ARM64_MODULE_PLTS SECTIONS { .plt (NOLOAD) : { BYTE(0) } .init.plt (NOLOAD) : { BYTE(0) } .text.ftrace_trampoline (NOLOAD) : { BYTE(0) } } +#endif diff --git a/arch/ia64/Makefile b/arch/ia64/Makefile index 2876a7df1b0a..703b1c4f6d12 100644 --- a/arch/ia64/Makefile +++ b/arch/ia64/Makefile @@ -20,7 +20,6 @@ CHECKFLAGS += -D__ia64=1 -D__ia64__=1 -D_LP64 -D__LP64__ OBJCOPYFLAGS := --strip-all LDFLAGS_vmlinux := -static -KBUILD_LDS_MODULE += $(srctree)/arch/ia64/module.lds KBUILD_AFLAGS_KERNEL := -mconstant-gp EXTRA := diff --git a/arch/ia64/module.lds b/arch/ia64/include/asm/module.lds.h similarity index 100% rename from arch/ia64/module.lds rename to arch/ia64/include/asm/module.lds.h diff --git a/arch/m68k/Makefile b/arch/m68k/Makefile index 4438ffb4bbe1..ea14f2046fb4 100644 --- a/arch/m68k/Makefile +++ b/arch/m68k/Makefile @@ -75,7 +75,6 @@ KBUILD_CPPFLAGS += -D__uClinux__ endif KBUILD_LDFLAGS := -m m68kelf -KBUILD_LDS_MODULE += $(srctree)/arch/m68k/kernel/module.lds ifdef CONFIG_SUN3 LDFLAGS_vmlinux = -N diff --git a/arch/m68k/kernel/module.lds b/arch/m68k/include/asm/module.lds.h similarity index 100% rename from arch/m68k/kernel/module.lds rename to arch/m68k/include/asm/module.lds.h diff --git a/arch/powerpc/Makefile b/arch/powerpc/Makefile index 3e8da9cf2eb9..8935658fcd06 100644 --- a/arch/powerpc/Makefile +++ b/arch/powerpc/Makefile @@ -65,7 +65,6 @@ UTS_MACHINE := $(subst $(space),,$(machine-y)) ifdef CONFIG_PPC32 KBUILD_LDFLAGS_MODULE += arch/powerpc/lib/crtsavres.o else -KBUILD_LDS_MODULE += $(srctree)/arch/powerpc/kernel/module.lds ifeq ($(call ld-ifversion, -ge, 225000000, y),y) # Have the linker provide sfpr if possible. # There is a corresponding test in arch/powerpc/lib/Makefile diff --git a/arch/powerpc/kernel/module.lds b/arch/powerpc/include/asm/module.lds.h similarity index 100% rename from arch/powerpc/kernel/module.lds rename to arch/powerpc/include/asm/module.lds.h diff --git a/arch/riscv/Makefile b/arch/riscv/Makefile index fb6e37db836d..8edaa8bd86d6 100644 --- a/arch/riscv/Makefile +++ b/arch/riscv/Makefile @@ -53,9 +53,6 @@ endif ifeq ($(CONFIG_CMODEL_MEDANY),y) KBUILD_CFLAGS += -mcmodel=medany endif -ifeq ($(CONFIG_MODULE_SECTIONS),y) - KBUILD_LDS_MODULE += $(srctree)/arch/riscv/kernel/module.lds -endif ifeq ($(CONFIG_PERF_EVENTS),y) KBUILD_CFLAGS += -fno-omit-frame-pointer endif diff --git a/arch/riscv/kernel/module.lds b/arch/riscv/include/asm/module.lds.h similarity index 84% rename from arch/riscv/kernel/module.lds rename to arch/riscv/include/asm/module.lds.h index 295ecfb341a2..4254ff2ff049 100644 --- a/arch/riscv/kernel/module.lds +++ b/arch/riscv/include/asm/module.lds.h @@ -1,8 +1,9 @@ /* SPDX-License-Identifier: GPL-2.0 */ /* Copyright (C) 2017 Andes Technology Corporation */ - +#ifdef CONFIG_MODULE_SECTIONS SECTIONS { .plt (NOLOAD) : { BYTE(0) } .got (NOLOAD) : { BYTE(0) } .got.plt (NOLOAD) : { BYTE(0) } } +#endif diff --git a/arch/um/include/asm/Kbuild b/arch/um/include/asm/Kbuild index 8d435f8a6dec..1c63b260ecc4 100644 --- a/arch/um/include/asm/Kbuild +++ b/arch/um/include/asm/Kbuild @@ -16,6 +16,7 @@ generic-y += kdebug.h generic-y += mcs_spinlock.h generic-y += mm-arch-hooks.h generic-y += mmiowb.h +generic-y += module.lds.h generic-y += param.h generic-y += pci.h generic-y += percpu.h diff --git a/include/asm-generic/Kbuild b/include/asm-generic/Kbuild index 74b0612601dd..7cd4e627e00e 100644 --- a/include/asm-generic/Kbuild +++ b/include/asm-generic/Kbuild @@ -40,6 +40,7 @@ mandatory-y += mmiowb.h mandatory-y += mmu.h mandatory-y += mmu_context.h mandatory-y += module.h +mandatory-y += module.lds.h mandatory-y += msi.h mandatory-y += pci.h mandatory-y += percpu.h diff --git a/include/asm-generic/module.lds.h b/include/asm-generic/module.lds.h new file mode 100644 index 000000000000..f210d5c1b78b --- /dev/null +++ b/include/asm-generic/module.lds.h @@ -0,0 +1,10 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +#ifndef __ASM_GENERIC_MODULE_LDS_H +#define __ASM_GENERIC_MODULE_LDS_H + +/* + * can specify arch-specific sections for linking modules. + * Empty for the asm-generic header. + */ + +#endif /* __ASM_GENERIC_MODULE_LDS_H */ diff --git a/scripts/.gitignore b/scripts/.gitignore index 0d1c8e217cd7..a6c11316c969 100644 --- a/scripts/.gitignore +++ b/scripts/.gitignore @@ -8,3 +8,4 @@ asn1_compiler extract-cert sign-file insert-sys-cert +/module.lds diff --git a/scripts/Makefile b/scripts/Makefile index bc018e4b733e..b5418ec587fb 100644 --- a/scripts/Makefile +++ b/scripts/Makefile @@ -29,6 +29,9 @@ endif # The following programs are only built on demand hostprogs += unifdef +# The module linker script is preprocessed on demand +targets += module.lds + subdir-$(CONFIG_GCC_PLUGINS) += gcc-plugins subdir-$(CONFIG_MODVERSIONS) += genksyms subdir-$(CONFIG_SECURITY_SELINUX) += selinux diff --git a/scripts/Makefile.modfinal b/scripts/Makefile.modfinal index 411c1e600e7d..ae01baf96f4e 100644 --- a/scripts/Makefile.modfinal +++ b/scripts/Makefile.modfinal @@ -33,11 +33,10 @@ quiet_cmd_ld_ko_o = LD [M] $@ cmd_ld_ko_o = \ $(LD) -r $(KBUILD_LDFLAGS) \ $(KBUILD_LDFLAGS_MODULE) $(LDFLAGS_MODULE) \ - $(addprefix -T , $(KBUILD_LDS_MODULE)) \ - -o $@ $(filter %.o, $^); \ + -T scripts/module.lds -o $@ $(filter %.o, $^); \ $(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true) -$(modules): %.ko: %.o %.mod.o $(KBUILD_LDS_MODULE) FORCE +$(modules): %.ko: %.o %.mod.o scripts/module.lds FORCE +$(call if_changed,ld_ko_o) targets += $(modules) $(modules:.ko=.mod.o) diff --git a/scripts/module-common.lds b/scripts/module.lds.S similarity index 93% rename from scripts/module-common.lds rename to scripts/module.lds.S index d61b9e8678e8..69b9b71a6a47 100644 --- a/scripts/module-common.lds +++ b/scripts/module.lds.S @@ -24,3 +24,6 @@ SECTIONS { __jump_table 0 : ALIGN(8) { KEEP(*(__jump_table)) } } + +/* bring in arch-specific sections */ +#include diff --git a/scripts/package/builddeb b/scripts/package/builddeb index 6df3c9f8b2da..44f212e37935 100755 --- a/scripts/package/builddeb +++ b/scripts/package/builddeb @@ -55,7 +55,7 @@ deploy_kernel_headers () { cd $srctree find . arch/$SRCARCH -maxdepth 1 -name Makefile\* find include scripts -type f -o -type l - find arch/$SRCARCH -name module.lds -o -name Kbuild.platforms -o -name Platform + find arch/$SRCARCH -name Kbuild.platforms -o -name Platform find $(find arch/$SRCARCH -name include -o -name scripts -type d) -type f ) > debian/hdrsrcfiles From patchwork Tue Oct 13 00:31:40 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sami Tolvanen X-Patchwork-Id: 11834549 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 D26D714D5 for ; Tue, 13 Oct 2020 00:32:36 +0000 (UTC) Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.kernel.org (Postfix) with SMTP id 0419521BE5 for ; Tue, 13 Oct 2020 00:32:35 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="IXTPLb0y" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0419521BE5 Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kernel-hardening-return-20175-patchwork-kernel-hardening=patchwork.kernel.org@lists.openwall.com Received: (qmail 11322 invoked by uid 550); 13 Oct 2020 00:32:22 -0000 Mailing-List: contact kernel-hardening-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Delivered-To: mailing list kernel-hardening@lists.openwall.com Received: (qmail 10185 invoked from network); 13 Oct 2020 00:32:22 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=sender:date:in-reply-to:message-id:mime-version:references:subject :from:to:cc; bh=TMDqK7SaU5cOFiGBMdZ8Uvp/vuFhiQD2dpfcaMKefDQ=; b=IXTPLb0yFS0o2Ga79gr7xdNEuO4HV13KRVxV2TTekWKuTZxx//v6pgCz5d15EYldkD BZ57RN/e61FhDemXvwUx/f/NWB6TRPm+Js/jxH+Ozhr38+xqoMr+mLGrfiRquS2j3kZJ fYrUrVndpVuef4YOld3pXFi3jcBOAwRlkcsfQZwg/xUdayEHuKtVYacnXMtm0b/I38Qx WxiKUnZ+mL2wNK3BuVJubCd8sZKHY38WZpOm/vNkaFMYl+vqbCp10u/22PEAKbjAh45D sMdah9r1FW+zKiF03OY7alXL/9E4fBd9YI1yEFlLk7unOBGLusyORO3j8boBtmXDyJax UZbw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=TMDqK7SaU5cOFiGBMdZ8Uvp/vuFhiQD2dpfcaMKefDQ=; b=ZsDQIF6Bzo8sR/2JlaP3+XqfmVg8cst07C7JvgBRFsfGqNzbdLwCqcn+nKbzgDyX0k VTxtgojAlasNRbAWf9emPO4hhm0b5ddX+v4n1kt8jZzh9JIg4+Ed9rhp7MZ7ED+fImfA YIaoMkeLtQbcBRGHXEklvswZhQmDI4F7YNUHdWapoIVPIKxvzm1/0pulChMrVXLg8yrL 7dUNrZ03l3XHLCY/59iSBqNkC/ok4lFJ7x+jF7HnPS8I9+MQJG/MJ0QHz1wjNT4JUB83 0FYgunjNFD68CiiJldxVHJnjXgZfYie9IePCUFf/QPfdTD7jPcG88uaWIFBthZTij3i7 1qOw== X-Gm-Message-State: AOAM532lN5lKZj4/HutBjHXoD6PA3cRiJiTWf1HVx/15oP7M289HPB75 ltkDOmkkViWGyo/azrNeTSgpkndeGvTpwZHmHiI= X-Google-Smtp-Source: ABdhPJzsd4CCmnhcLZkBRbfSKkJeEB8ZYCNEDRSF1U6z3faMrYXBKcMOZdLok8oHysnniolDxRFIZGt/9cwSiZFRwQU= Sender: "samitolvanen via sendgmr" X-Received: from samitolvanen1.mtv.corp.google.com ([2620:15c:201:2:f693:9fff:fef4:1b6d]) (user=samitolvanen job=sendgmr) by 2002:a17:90a:940c:: with SMTP id r12mr3210626pjo.1.1602549129256; Mon, 12 Oct 2020 17:32:09 -0700 (PDT) Date: Mon, 12 Oct 2020 17:31:40 -0700 In-Reply-To: <20201013003203.4168817-1-samitolvanen@google.com> Message-Id: <20201013003203.4168817-3-samitolvanen@google.com> Mime-Version: 1.0 References: <20201013003203.4168817-1-samitolvanen@google.com> X-Mailer: git-send-email 2.28.0.1011.ga647a8990f-goog Subject: [PATCH v6 02/25] objtool: Add a pass for generating __mcount_loc From: Sami Tolvanen To: Masahiro Yamada , Steven Rostedt Cc: Will Deacon , Peter Zijlstra , Greg Kroah-Hartman , "Paul E. McKenney" , Kees Cook , Nick Desaulniers , clang-built-linux@googlegroups.com, kernel-hardening@lists.openwall.com, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, x86@kernel.org, Sami Tolvanen From: Peter Zijlstra Add the --mcount option for generating __mcount_loc sections needed for dynamic ftrace. Using this pass requires the kernel to be compiled with -mfentry and CC_USING_NOP_MCOUNT to be defined in Makefile. Link: https://lore.kernel.org/lkml/20200625200235.GQ4781@hirez.programming.kicks-ass.net/ Signed-off-by: Peter Zijlstra [Sami: rebased, dropped config changes, fixed to actually use --mcount, and wrote a commit message.] Signed-off-by: Sami Tolvanen Reviewed-by: Kees Cook --- tools/objtool/builtin-check.c | 3 +- tools/objtool/builtin.h | 2 +- tools/objtool/check.c | 82 +++++++++++++++++++++++++++++++++++ tools/objtool/check.h | 1 + tools/objtool/objtool.c | 1 + tools/objtool/objtool.h | 1 + 6 files changed, 88 insertions(+), 2 deletions(-) diff --git a/tools/objtool/builtin-check.c b/tools/objtool/builtin-check.c index c6d199bfd0ae..e92e76f69176 100644 --- a/tools/objtool/builtin-check.c +++ b/tools/objtool/builtin-check.c @@ -18,7 +18,7 @@ #include "builtin.h" #include "objtool.h" -bool no_fp, no_unreachable, retpoline, module, backtrace, uaccess, stats, validate_dup, vmlinux; +bool no_fp, no_unreachable, retpoline, module, backtrace, uaccess, stats, validate_dup, vmlinux, mcount; static const char * const check_usage[] = { "objtool check [] file.o", @@ -35,6 +35,7 @@ const struct option check_options[] = { OPT_BOOLEAN('s', "stats", &stats, "print statistics"), OPT_BOOLEAN('d', "duplicate", &validate_dup, "duplicate validation for vmlinux.o"), OPT_BOOLEAN('l', "vmlinux", &vmlinux, "vmlinux.o validation"), + OPT_BOOLEAN('M', "mcount", &mcount, "generate __mcount_loc"), OPT_END(), }; diff --git a/tools/objtool/builtin.h b/tools/objtool/builtin.h index 85c979caa367..94565a72b701 100644 --- a/tools/objtool/builtin.h +++ b/tools/objtool/builtin.h @@ -8,7 +8,7 @@ #include extern const struct option check_options[]; -extern bool no_fp, no_unreachable, retpoline, module, backtrace, uaccess, stats, validate_dup, vmlinux; +extern bool no_fp, no_unreachable, retpoline, module, backtrace, uaccess, stats, validate_dup, vmlinux, mcount; extern int cmd_check(int argc, const char **argv); extern int cmd_orc(int argc, const char **argv); diff --git a/tools/objtool/check.c b/tools/objtool/check.c index c6ab44543c92..c39c4d2b432a 100644 --- a/tools/objtool/check.c +++ b/tools/objtool/check.c @@ -523,6 +523,65 @@ static int create_static_call_sections(struct objtool_file *file) return 0; } +static int create_mcount_loc_sections(struct objtool_file *file) +{ + struct section *sec, *reloc_sec; + struct reloc *reloc; + unsigned long *loc; + struct instruction *insn; + int idx; + + sec = find_section_by_name(file->elf, "__mcount_loc"); + if (sec) { + INIT_LIST_HEAD(&file->mcount_loc_list); + WARN("file already has __mcount_loc section, skipping"); + return 0; + } + + if (list_empty(&file->mcount_loc_list)) + return 0; + + idx = 0; + list_for_each_entry(insn, &file->mcount_loc_list, mcount_loc_node) + idx++; + + sec = elf_create_section(file->elf, "__mcount_loc", 0, sizeof(unsigned long), idx); + if (!sec) + return -1; + + reloc_sec = elf_create_reloc_section(file->elf, sec, SHT_RELA); + if (!reloc_sec) + return -1; + + idx = 0; + list_for_each_entry(insn, &file->mcount_loc_list, mcount_loc_node) { + + loc = (unsigned long *)sec->data->d_buf + idx; + memset(loc, 0, sizeof(unsigned long)); + + reloc = malloc(sizeof(*reloc)); + if (!reloc) { + perror("malloc"); + return -1; + } + memset(reloc, 0, sizeof(*reloc)); + + reloc->sym = insn->sec->sym; + reloc->addend = insn->offset; + reloc->type = R_X86_64_64; + reloc->offset = idx * sizeof(unsigned long); + reloc->sec = reloc_sec; + elf_add_reloc(file->elf, reloc); + + idx++; + } + + if (elf_rebuild_reloc_section(file->elf, reloc_sec)) + return -1; + + return 0; +} + /* * Warnings shouldn't be reported for ignored functions. */ @@ -949,6 +1008,22 @@ static int add_call_destinations(struct objtool_file *file) insn->type = INSN_NOP; } + if (mcount && !strcmp(insn->call_dest->name, "__fentry__")) { + if (reloc) { + reloc->type = R_NONE; + elf_write_reloc(file->elf, reloc); + } + + elf_write_insn(file->elf, insn->sec, + insn->offset, insn->len, + arch_nop_insn(insn->len)); + + insn->type = INSN_NOP; + + list_add_tail(&insn->mcount_loc_node, + &file->mcount_loc_list); + } + /* * Whatever stack impact regular CALLs have, should be undone * by the RETURN of the called function. @@ -2920,6 +2995,13 @@ int check(struct objtool_file *file) goto out; warnings += ret; + if (mcount) { + ret = create_mcount_loc_sections(file); + if (ret < 0) + goto out; + warnings += ret; + } + out: if (ret < 0) { /* diff --git a/tools/objtool/check.h b/tools/objtool/check.h index 5ec00a4b891b..070baec2050a 100644 --- a/tools/objtool/check.h +++ b/tools/objtool/check.h @@ -23,6 +23,7 @@ struct instruction { struct list_head list; struct hlist_node hash; struct list_head static_call_node; + struct list_head mcount_loc_node; struct section *sec; unsigned long offset; unsigned int len; diff --git a/tools/objtool/objtool.c b/tools/objtool/objtool.c index 9df0cd86d310..c1819a6f2a18 100644 --- a/tools/objtool/objtool.c +++ b/tools/objtool/objtool.c @@ -62,6 +62,7 @@ struct objtool_file *objtool_open_read(const char *_objname) INIT_LIST_HEAD(&file.insn_list); hash_init(file.insn_hash); INIT_LIST_HEAD(&file.static_call_list); + INIT_LIST_HEAD(&file.mcount_loc_list); file.c_file = !vmlinux && find_section_by_name(file.elf, ".comment"); file.ignore_unreachables = no_unreachable; file.hints = false; diff --git a/tools/objtool/objtool.h b/tools/objtool/objtool.h index 4125d4578b23..cf004dd60c2b 100644 --- a/tools/objtool/objtool.h +++ b/tools/objtool/objtool.h @@ -19,6 +19,7 @@ struct objtool_file { struct list_head insn_list; DECLARE_HASHTABLE(insn_hash, 20); struct list_head static_call_list; + struct list_head mcount_loc_list; bool ignore_unreachables, c_file, hints, rodata; }; From patchwork Tue Oct 13 00:31:41 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sami Tolvanen X-Patchwork-Id: 11834551 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 3BE2D92C for ; Tue, 13 Oct 2020 00:32:46 +0000 (UTC) Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.kernel.org (Postfix) with SMTP id 8DC7021655 for ; Tue, 13 Oct 2020 00:32:45 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="qUa1vHHc" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8DC7021655 Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kernel-hardening-return-20176-patchwork-kernel-hardening=patchwork.kernel.org@lists.openwall.com Received: (qmail 11480 invoked by uid 550); 13 Oct 2020 00:32:24 -0000 Mailing-List: contact kernel-hardening-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Delivered-To: mailing list kernel-hardening@lists.openwall.com Received: (qmail 11329 invoked from network); 13 Oct 2020 00:32:23 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=sender:date:in-reply-to:message-id:mime-version:references:subject :from:to:cc; bh=kVJaNW7eSaj0HFfwrYDw0RQeIfteodxyLLwn3XkvFZA=; b=qUa1vHHcZgq+GOQlX2iLACARLoC/9h8vfuF9kwmVqVXA6Ay82zVe3uxoPk7oE9G3a5 qspmhivovZKsl7zTe/TB3hhhY10WADRHi+k8hnkVHAdhubXLpnUEkMhxCS4DpvzY4fG5 PHSzJ/adCJ3UEYsP53P7E1DazaOwM3ZH1sxI6dX+vcxypIOCYcQNAdiKAN+VBaDFVnEm 8IPYRyR+hoO/wI0KaLDF4HCza/Ja8k6r7MrNh/bpFr8Hc/LwI0gzp5Wcj5mZmwtbzUgg SiAlpC4qMNr7O/bt2XOuW/rZtWiM/XRlM4/puqQkxdt2vQoQuYb0S+oJ1E4MnJy4FDei mUPg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=kVJaNW7eSaj0HFfwrYDw0RQeIfteodxyLLwn3XkvFZA=; b=uLNFT908nHJ7+vJtAOruiA3ChfXkgYBCqmJOTmIVELAxomRpzBBBU6ftB2JdAPb+K2 IxKHlt6eEEOFwsMa2D2IJTM4yZ9DZkxmgd+XaiZxB9lNLzrzrIorvQ8VS8nZswga87li CmPTUqLI9F2zuQlwpdojiD702ml11KvEr4oeHkovPvW0/YVu+h0opQJ51VSUaVbva7Vq bQ/siqi/ROJqhKRq8PvSLoMWjs+cWtbqpnBSvPpvtaRCvktod3n9NZ40Fzf5cmcCU6wx n3wMRj0DyfzGxsBhcPDo4t5ZY1mZOIKQ1p2resBlPZBiQmCKWJ68alyPwNVaSh82MbMe R6rw== X-Gm-Message-State: AOAM532+svNFGPeF83pYIM8KURgA3ayQDBaJRiCWbrawkl7JPFT9mN// X9nF1RH/n5hfltzbYPbOIzP5USncKasMWfPgymM= X-Google-Smtp-Source: ABdhPJxxVxVLXATH28VAjZYJvCMjRNOfP6FG+zwrqzoHwd+tVOzS3ssjn2tzJdDq4rR6gIG7Z06UGW92/5YWikencXY= Sender: "samitolvanen via sendgmr" X-Received: from samitolvanen1.mtv.corp.google.com ([2620:15c:201:2:f693:9fff:fef4:1b6d]) (user=samitolvanen job=sendgmr) by 2002:ad4:5843:: with SMTP id de3mr28374099qvb.12.1602549131356; Mon, 12 Oct 2020 17:32:11 -0700 (PDT) Date: Mon, 12 Oct 2020 17:31:41 -0700 In-Reply-To: <20201013003203.4168817-1-samitolvanen@google.com> Message-Id: <20201013003203.4168817-4-samitolvanen@google.com> Mime-Version: 1.0 References: <20201013003203.4168817-1-samitolvanen@google.com> X-Mailer: git-send-email 2.28.0.1011.ga647a8990f-goog Subject: [PATCH v6 03/25] objtool: Don't autodetect vmlinux.o From: Sami Tolvanen To: Masahiro Yamada , Steven Rostedt Cc: Will Deacon , Peter Zijlstra , Greg Kroah-Hartman , "Paul E. McKenney" , Kees Cook , Nick Desaulniers , clang-built-linux@googlegroups.com, kernel-hardening@lists.openwall.com, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, x86@kernel.org, Sami Tolvanen With LTO, we run objtool on vmlinux.o, but don't want noinstr validation. This change requires --vmlinux to be passed to objtool explicitly. Suggested-by: Peter Zijlstra Signed-off-by: Sami Tolvanen Reviewed-by: Kees Cook --- scripts/link-vmlinux.sh | 2 +- tools/objtool/builtin-check.c | 6 +----- 2 files changed, 2 insertions(+), 6 deletions(-) diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh index e6e2d9e5ff48..372c3719f94c 100755 --- a/scripts/link-vmlinux.sh +++ b/scripts/link-vmlinux.sh @@ -64,7 +64,7 @@ objtool_link() local objtoolopt; if [ -n "${CONFIG_VMLINUX_VALIDATION}" ]; then - objtoolopt="check" + objtoolopt="check --vmlinux" if [ -z "${CONFIG_FRAME_POINTER}" ]; then objtoolopt="${objtoolopt} --no-fp" fi diff --git a/tools/objtool/builtin-check.c b/tools/objtool/builtin-check.c index e92e76f69176..facfc10bc5dc 100644 --- a/tools/objtool/builtin-check.c +++ b/tools/objtool/builtin-check.c @@ -41,7 +41,7 @@ const struct option check_options[] = { int cmd_check(int argc, const char **argv) { - const char *objname, *s; + const char *objname; struct objtool_file *file; int ret; @@ -52,10 +52,6 @@ int cmd_check(int argc, const char **argv) objname = argv[0]; - s = strstr(objname, "vmlinux.o"); - if (s && !s[9]) - vmlinux = true; - file = objtool_open_read(objname); if (!file) return 1; From patchwork Tue Oct 13 00:31:42 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sami Tolvanen X-Patchwork-Id: 11834553 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 782FE92C for ; Tue, 13 Oct 2020 00:32:54 +0000 (UTC) Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.kernel.org (Postfix) with SMTP id 6D10F218AC for ; Tue, 13 Oct 2020 00:32:53 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="qUGfJyLp" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6D10F218AC Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kernel-hardening-return-20177-patchwork-kernel-hardening=patchwork.kernel.org@lists.openwall.com Received: (qmail 11685 invoked by uid 550); 13 Oct 2020 00:32:26 -0000 Mailing-List: contact kernel-hardening-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Delivered-To: mailing list kernel-hardening@lists.openwall.com Received: (qmail 11525 invoked from network); 13 Oct 2020 00:32:24 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=sender:date:in-reply-to:message-id:mime-version:references:subject :from:to:cc; bh=f2KSu+z7jDKn/rdJa/Ip0wrfAi6otBE8x5RUzQIqnlQ=; b=qUGfJyLpLmfej5ayabZKu5Bx4lT6/dyQBaJieiAyUkElQNJXRTsFGO3tBSTM0lH2WA E8V9ctIk3cowUGCLCj+ga8NWhuW8IsfwOiJPG1VpvW+N9kqDnIZHA2+bYHE9+JVl/qUy HkLMvl1JsNGiHimiSWLmswdh++6c+veGwVRY0BjKT7ZP8U4LeGCMRGB4XDAMh69ghBO/ 5nFy/ZHge5bmVUXcC9MrHZlc3Xr5nTl0ryjhWHaz5aNwTpnOR/W3z6l/IOWulBcFblgs 8AEBWXHGSuLlm30LeIElRQ+qmxGsBMMzGPECrypA4+EfaFSAGSv0sR/xXe5bUivu5Azc zG5A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=f2KSu+z7jDKn/rdJa/Ip0wrfAi6otBE8x5RUzQIqnlQ=; b=sUlemNo6ZkQZIWc6S6bGdhOQ7gytBII27A1iEVAqoI71yNo9C/SytwgmXC3ZEs/8vZ wCJpnMx1s0zm1+t8OFh8KqpLfsexvQ0XpCgOG3oaBF85hoxir/FU6Wa2TCkLc5WAWXwG zEpKTweszCqeZEB2m95C3M4X0NVQDIlx4/7xSHrQgMLd0i+82vjcvc3xtwFZe3ckZeeP r9WJJo7oWrr+G6QJNXlZRBXw3GZ0GRTASkS4QnqprJ5u5AHAyoil/Ib9DgYLOwpoUoib YonBXp4H+UcMDtdsoKfa51WnLlYkSWMchf4MtN/ey6/p/Gu5fI4D1Qhnf+UApW66Z2HG u5lg== X-Gm-Message-State: AOAM532xUt8w1NOIx3NGW70WuPE/f7FgGRFUaE3krxfkPjGqZxpOrpt/ /nt0/xKJ5LjP0+YLN0jagWvpufStkk8uv4RqkvQ= X-Google-Smtp-Source: ABdhPJx/eVhqbFhuf8A/9RKbRt5xAPrKG8l+BlgeU9T8uNxkYkRthW5oOA8rtJHTS4Ep1kI0dRFFhyGDS7i3dzc9NJc= Sender: "samitolvanen via sendgmr" X-Received: from samitolvanen1.mtv.corp.google.com ([2620:15c:201:2:f693:9fff:fef4:1b6d]) (user=samitolvanen job=sendgmr) by 2002:a0c:e5cf:: with SMTP id u15mr27081552qvm.24.1602549133091; Mon, 12 Oct 2020 17:32:13 -0700 (PDT) Date: Mon, 12 Oct 2020 17:31:42 -0700 In-Reply-To: <20201013003203.4168817-1-samitolvanen@google.com> Message-Id: <20201013003203.4168817-5-samitolvanen@google.com> Mime-Version: 1.0 References: <20201013003203.4168817-1-samitolvanen@google.com> X-Mailer: git-send-email 2.28.0.1011.ga647a8990f-goog Subject: [PATCH v6 04/25] tracing: move function tracer options to Kconfig From: Sami Tolvanen To: Masahiro Yamada , Steven Rostedt Cc: Will Deacon , Peter Zijlstra , Greg Kroah-Hartman , "Paul E. McKenney" , Kees Cook , Nick Desaulniers , clang-built-linux@googlegroups.com, kernel-hardening@lists.openwall.com, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, x86@kernel.org, Sami Tolvanen Move function tracer options to Kconfig to make it easier to add new methods for generating __mcount_loc, and to make the options available also when building kernel modules. Note that FTRACE_MCOUNT_USE_* options are updated on rebuild and therefore, work even if the .config was generated in a different environment. Signed-off-by: Sami Tolvanen --- Makefile | 20 ++++++++------------ kernel/trace/Kconfig | 16 ++++++++++++++++ scripts/Makefile.build | 6 ++---- 3 files changed, 26 insertions(+), 16 deletions(-) diff --git a/Makefile b/Makefile index 0dcf302fe2da..129001b38357 100644 --- a/Makefile +++ b/Makefile @@ -841,12 +841,8 @@ KBUILD_CFLAGS += $(DEBUG_CFLAGS) export DEBUG_CFLAGS ifdef CONFIG_FUNCTION_TRACER -ifdef CONFIG_FTRACE_MCOUNT_RECORD - # gcc 5 supports generating the mcount tables directly - ifeq ($(call cc-option-yn,-mrecord-mcount),y) - CC_FLAGS_FTRACE += -mrecord-mcount - export CC_USING_RECORD_MCOUNT := 1 - endif +ifdef CONFIG_FTRACE_MCOUNT_USE_CC + CC_FLAGS_FTRACE += -mrecord-mcount ifdef CONFIG_HAVE_NOP_MCOUNT ifeq ($(call cc-option-yn, -mnop-mcount),y) CC_FLAGS_FTRACE += -mnop-mcount @@ -854,6 +850,12 @@ ifdef CONFIG_FTRACE_MCOUNT_RECORD endif endif endif +ifdef CONFIG_FTRACE_MCOUNT_USE_RECORDMCOUNT + ifdef CONFIG_HAVE_C_RECORDMCOUNT + BUILD_C_RECORDMCOUNT := y + export BUILD_C_RECORDMCOUNT + endif +endif ifdef CONFIG_HAVE_FENTRY ifeq ($(call cc-option-yn, -mfentry),y) CC_FLAGS_FTRACE += -mfentry @@ -863,12 +865,6 @@ endif export CC_FLAGS_FTRACE KBUILD_CFLAGS += $(CC_FLAGS_FTRACE) $(CC_FLAGS_USING) KBUILD_AFLAGS += $(CC_FLAGS_USING) -ifdef CONFIG_DYNAMIC_FTRACE - ifdef CONFIG_HAVE_C_RECORDMCOUNT - BUILD_C_RECORDMCOUNT := y - export BUILD_C_RECORDMCOUNT - endif -endif endif # We trigger additional mismatches with less inlining diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig index a4020c0b4508..927ad004888a 100644 --- a/kernel/trace/Kconfig +++ b/kernel/trace/Kconfig @@ -595,6 +595,22 @@ config FTRACE_MCOUNT_RECORD depends on DYNAMIC_FTRACE depends on HAVE_FTRACE_MCOUNT_RECORD +config FTRACE_MCOUNT_USE_PATCHABLE_FUNCTION_ENTRY + bool + depends on FTRACE_MCOUNT_RECORD + +config FTRACE_MCOUNT_USE_CC + def_bool y + depends on $(cc-option,-mrecord-mcount) + depends on !FTRACE_MCOUNT_USE_PATCHABLE_FUNCTION_ENTRY + depends on FTRACE_MCOUNT_RECORD + +config FTRACE_MCOUNT_USE_RECORDMCOUNT + def_bool y + depends on !FTRACE_MCOUNT_USE_PATCHABLE_FUNCTION_ENTRY + depends on !FTRACE_MCOUNT_USE_CC + depends on FTRACE_MCOUNT_RECORD + config TRACING_MAP bool depends on ARCH_HAVE_NMI_SAFE_CMPXCHG diff --git a/scripts/Makefile.build b/scripts/Makefile.build index a467b9323442..a4634aae1506 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -178,8 +178,7 @@ cmd_modversions_c = \ fi endif -ifdef CONFIG_FTRACE_MCOUNT_RECORD -ifndef CC_USING_RECORD_MCOUNT +ifdef CONFIG_FTRACE_MCOUNT_USE_RECORDMCOUNT # compiler will not generate __mcount_loc use recordmcount or recordmcount.pl ifdef BUILD_C_RECORDMCOUNT ifeq ("$(origin RECORDMCOUNT_WARN)", "command line") @@ -206,8 +205,7 @@ recordmcount_source := $(srctree)/scripts/recordmcount.pl endif # BUILD_C_RECORDMCOUNT cmd_record_mcount = $(if $(findstring $(strip $(CC_FLAGS_FTRACE)),$(_c_flags)), \ $(sub_cmd_record_mcount)) -endif # CC_USING_RECORD_MCOUNT -endif # CONFIG_FTRACE_MCOUNT_RECORD +endif # CONFIG_FTRACE_MCOUNT_USE_RECORDMCOUNT ifdef CONFIG_STACK_VALIDATION ifneq ($(SKIP_STACK_VALIDATION),1) From patchwork Tue Oct 13 00:31:43 2020 Content-Type: text/plain; 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McKenney" , Kees Cook , Nick Desaulniers , clang-built-linux@googlegroups.com, kernel-hardening@lists.openwall.com, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, x86@kernel.org, Sami Tolvanen This change adds build support for using objtool to generate __mcount_loc sections. Signed-off-by: Sami Tolvanen --- Makefile | 12 ++++++++++-- kernel/trace/Kconfig | 13 +++++++++++++ scripts/Makefile.build | 3 +++ 3 files changed, 26 insertions(+), 2 deletions(-) diff --git a/Makefile b/Makefile index 129001b38357..fda1f8a0b1c7 100644 --- a/Makefile +++ b/Makefile @@ -850,6 +850,9 @@ ifdef CONFIG_FTRACE_MCOUNT_USE_CC endif endif endif +ifdef CONFIG_FTRACE_MCOUNT_USE_OBJTOOL + CC_FLAGS_USING += -DCC_USING_NOP_MCOUNT +endif ifdef CONFIG_FTRACE_MCOUNT_USE_RECORDMCOUNT ifdef CONFIG_HAVE_C_RECORDMCOUNT BUILD_C_RECORDMCOUNT := y @@ -1209,11 +1212,16 @@ uapi-asm-generic: PHONY += prepare-objtool prepare-resolve_btfids prepare-objtool: $(objtool_target) ifeq ($(SKIP_STACK_VALIDATION),1) +objtool-lib-prompt := "please install libelf-dev, libelf-devel or elfutils-libelf-devel" +ifdef CONFIG_FTRACE_MCOUNT_USE_OBJTOOL + @echo "error: Cannot generate __mcount_loc for CONFIG_DYNAMIC_FTRACE=y, $(objtool-lib-prompt)" >&2 + @false +endif ifdef CONFIG_UNWINDER_ORC - @echo "error: Cannot generate ORC metadata for CONFIG_UNWINDER_ORC=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2 + @echo "error: Cannot generate ORC metadata for CONFIG_UNWINDER_ORC=y, $(objtool-lib-prompt)" >&2 @false else - @echo "warning: Cannot use CONFIG_STACK_VALIDATION=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2 + @echo "warning: Cannot use CONFIG_STACK_VALIDATION=y, $(objtool-lib-prompt)" >&2 endif endif diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig index 927ad004888a..89263210ab26 100644 --- a/kernel/trace/Kconfig +++ b/kernel/trace/Kconfig @@ -51,6 +51,11 @@ config HAVE_NOP_MCOUNT help Arch supports the gcc options -pg with -mrecord-mcount and -nop-mcount +config HAVE_OBJTOOL_MCOUNT + bool + help + Arch supports objtool --mcount + config HAVE_C_RECORDMCOUNT bool help @@ -605,10 +610,18 @@ config FTRACE_MCOUNT_USE_CC depends on !FTRACE_MCOUNT_USE_PATCHABLE_FUNCTION_ENTRY depends on FTRACE_MCOUNT_RECORD +config FTRACE_MCOUNT_USE_OBJTOOL + def_bool y + depends on HAVE_OBJTOOL_MCOUNT + depends on !FTRACE_MCOUNT_USE_PATCHABLE_FUNCTION_ENTRY + depends on !FTRACE_MCOUNT_USE_CC + depends on FTRACE_MCOUNT_RECORD + config FTRACE_MCOUNT_USE_RECORDMCOUNT def_bool y depends on !FTRACE_MCOUNT_USE_PATCHABLE_FUNCTION_ENTRY depends on !FTRACE_MCOUNT_USE_CC + depends on !FTRACE_MCOUNT_USE_OBJTOOL depends on FTRACE_MCOUNT_RECORD config TRACING_MAP diff --git a/scripts/Makefile.build b/scripts/Makefile.build index a4634aae1506..cd4294435fef 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -228,6 +228,9 @@ endif ifdef CONFIG_X86_SMAP objtool_args += --uaccess endif +ifdef CONFIG_FTRACE_MCOUNT_USE_OBJTOOL + objtool_args += --mcount +endif # 'OBJECT_FILES_NON_STANDARD := y': skip objtool checking for a directory # 'OBJECT_FILES_NON_STANDARD_foo.o := 'y': skip objtool checking for a file From patchwork Tue Oct 13 00:31:44 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sami Tolvanen X-Patchwork-Id: 11834557 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 ADC4592C for ; Tue, 13 Oct 2020 00:33:10 +0000 (UTC) Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.kernel.org (Postfix) with SMTP id F1F8F218AC for ; Tue, 13 Oct 2020 00:33:09 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="IdXB04m+" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org F1F8F218AC Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kernel-hardening-return-20179-patchwork-kernel-hardening=patchwork.kernel.org@lists.openwall.com Received: (qmail 12081 invoked by uid 550); 13 Oct 2020 00:32:30 -0000 Mailing-List: contact kernel-hardening-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Delivered-To: mailing list kernel-hardening@lists.openwall.com Received: (qmail 11982 invoked from network); 13 Oct 2020 00:32:29 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=sender:date:in-reply-to:message-id:mime-version:references:subject :from:to:cc; bh=xL7tn5bk8rd7QhzERnW5XDCxrWNQLuaGbP7lLdALs6Y=; b=IdXB04m+VIhq9Ywfk+Q6SdQxAtxltKDIhWNIfo+jhdLwgrlbdcpJkCD1dg60k4KicG 1IgqLYFzJP4YEVrqWrx9pldSCsrIUIQZ+WBgBNy02BbQgKQE7dyYmjEiSSvKFbyI2xXj TV/V2tWK25kaN3vgAN5S+M0sENDBoc3aH1FQDGeTof6qqw+rbjH3bLU8q4fusukkB6D6 mAux60p4YIG3jSjYIx2pWv96v7XCJ9hy4Ka8a16xDIx9CMpYSDwuHtmOn9Zpz0sBYoxo n76+DpbDHdACleamKfcxERH+Pqgb3G4b5AAOxxW5ydqXddcuIHi5FDSPpeBjiqI6FIaq F5XQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=xL7tn5bk8rd7QhzERnW5XDCxrWNQLuaGbP7lLdALs6Y=; b=Fkdh3VI10Ho1sNEugBA/6r8lBfyazxJPwMlRGqEVFPBIWXalh7RZdOPbNYXej23Boj /hQkKubItDD86umsQoCdRiSdbqRbZ4FQYYwWoWKnOyo+Lo6CS3oEd0tZumtKApNCrYBG x3onJlALKnHyE2g/pQ/tb3zNrx1HYPf59dz0CZzUkMrRr0HYptT+UCPYI1WBFXRr6IPa kj7HGYz+2Ljap0cnsaMV5KGoTqh9I/eLLhpmdZkjn6qtC5kCL1hj5MK6UV8eINlE4gJK tZlD1+Zaedy/BrKCwTd7kLPXcdJ0n4pN+aPI/5Y751Eg8R9+e4GBMvDHv5HfKZ8h3zLy cEkg== X-Gm-Message-State: AOAM532xEjdT1otfvDaxz7qX9iZn0fVJc4o2usfZY3BLKsWXpC+0xTsG YsKkhN6nxr4Qm9kF6kd1t4i5WKBcxYRPC4mD/aA= X-Google-Smtp-Source: ABdhPJzmHD4XCersd5eY8ZPVkbKw3ea3PfM0fSiP3AGN8FM08tkamilxzFI74ZhTfsYbcW37PW4YYLWgNBpJiUusVu4= Sender: "samitolvanen via sendgmr" X-Received: from samitolvanen1.mtv.corp.google.com ([2620:15c:201:2:f693:9fff:fef4:1b6d]) (user=samitolvanen job=sendgmr) by 2002:aa7:9a87:0:b029:156:5806:b478 with SMTP id w7-20020aa79a870000b02901565806b478mr3079925pfi.8.1602549137181; Mon, 12 Oct 2020 17:32:17 -0700 (PDT) Date: Mon, 12 Oct 2020 17:31:44 -0700 In-Reply-To: <20201013003203.4168817-1-samitolvanen@google.com> Message-Id: <20201013003203.4168817-7-samitolvanen@google.com> Mime-Version: 1.0 References: <20201013003203.4168817-1-samitolvanen@google.com> X-Mailer: git-send-email 2.28.0.1011.ga647a8990f-goog Subject: [PATCH v6 06/25] x86, build: use objtool mcount From: Sami Tolvanen To: Masahiro Yamada , Steven Rostedt Cc: Will Deacon , Peter Zijlstra , Greg Kroah-Hartman , "Paul E. McKenney" , Kees Cook , Nick Desaulniers , clang-built-linux@googlegroups.com, kernel-hardening@lists.openwall.com, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, x86@kernel.org, Sami Tolvanen Select HAVE_OBJTOOL_MCOUNT if STACK_VALIDATION is selected to use objtool to generate __mcount_loc sections for dynamic ftrace with Clang and gcc <5 (later versions of gcc use -mrecord-mcount). Signed-off-by: Sami Tolvanen Reviewed-by: Kees Cook --- arch/x86/Kconfig | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 5e832fd520b5..6d67646153bc 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -163,6 +163,7 @@ config X86 select HAVE_CMPXCHG_LOCAL select HAVE_CONTEXT_TRACKING if X86_64 select HAVE_C_RECORDMCOUNT + select HAVE_OBJTOOL_MCOUNT if STACK_VALIDATION select HAVE_DEBUG_KMEMLEAK select HAVE_DMA_CONTIGUOUS select HAVE_DYNAMIC_FTRACE From patchwork Tue Oct 13 00:31:45 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sami Tolvanen X-Patchwork-Id: 11834561 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 BB14B14D5 for ; Tue, 13 Oct 2020 00:33:19 +0000 (UTC) Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.kernel.org (Postfix) with SMTP id 1910E216C4 for ; Tue, 13 Oct 2020 00:33:18 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="tToV5WHA" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1910E216C4 Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kernel-hardening-return-20180-patchwork-kernel-hardening=patchwork.kernel.org@lists.openwall.com Received: (qmail 12276 invoked by uid 550); 13 Oct 2020 00:32:31 -0000 Mailing-List: contact kernel-hardening-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Delivered-To: mailing list kernel-hardening@lists.openwall.com Received: (qmail 12175 invoked from network); 13 Oct 2020 00:32:30 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=sender:date:in-reply-to:message-id:mime-version:references:subject :from:to:cc; bh=DpKDWbKTWTks9tV0s5R4bAv6I99K4U3GWyHtOORPWq0=; b=tToV5WHAo5KqbZWvmvK6V50kBP7lFH3FOB2CpC/8vUKu1aRiVvkQ0yMN0vQ89CF6e5 JRyw7EkAwMm6H7peFQHQIMNjEArgToT8cMngzUtewp6pjEsEnKihkjsnBtvO6oPWyoY5 0jEoVe5t1I0r/WTDYyCiLYBEDIC8osSOQ1G5cl4z6TNyAQclWkSSmuTXoRh0op1Xl5s4 0Q1DPTZbYn6GTjC25XWRmtS3tD3Yc9zFyn9Pd4h3pvxgPKUIZShi/wu0rDWou0nHcj7q RIn/E/s2/75f3avHOb7sHbB3x3aWYsCQGwnME8C9IgglpttXQYXa7cI9BcTPqzUO1vEH +83Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=DpKDWbKTWTks9tV0s5R4bAv6I99K4U3GWyHtOORPWq0=; b=WIM02BKYhWX82qOnG9TpByzvFMGllnTzNa5QfSq7apRJTbkI+Kdzj1L+L/t2ETKUCT um4YtMlmH+PYeg0CseQpnOc/gDdzr04PCvdNkyWHjIoP6A7ynk4g55CoDZSSg443ub+g LFrl8a6H/pLv65lvQQ0LLybHVB0T8rcmgq2gRx45zP9otojL3Qg58gbWKatmiyVR/c8Z 1U6TuLXPK+hw8gWVapy+8mud00nNod88Zi030ezqMcUHma95/d9bjXWzQn290+/Pw1tc IMXRmgaDmOB9ODvzAPdDlu2gCndXkhfrNMjwfK8WaxV55hALGZEGvk5lpOKmlvQ12QxE KDcQ== X-Gm-Message-State: AOAM532OqXH7NCtKr4IHdz6C3F9xHWbLXepszuiH1zM0YZY/i6avKfBC xRQY1Brhp7OPcVsxPgF5UOvPi4/lpYLMhMH/qIM= X-Google-Smtp-Source: ABdhPJx3VxsNQ9tGu8xO95a1t6wVsoYxq4cLAxTVRK8Lq6kP9gEUNleSTLK5SuOy50JiEDn6GMUiyP2OF00DUvOhVxA= Sender: "samitolvanen via sendgmr" X-Received: from samitolvanen1.mtv.corp.google.com ([2620:15c:201:2:f693:9fff:fef4:1b6d]) (user=samitolvanen job=sendgmr) by 2002:a0c:e1d1:: with SMTP id v17mr25826493qvl.15.1602549139059; Mon, 12 Oct 2020 17:32:19 -0700 (PDT) Date: Mon, 12 Oct 2020 17:31:45 -0700 In-Reply-To: <20201013003203.4168817-1-samitolvanen@google.com> Message-Id: <20201013003203.4168817-8-samitolvanen@google.com> Mime-Version: 1.0 References: <20201013003203.4168817-1-samitolvanen@google.com> X-Mailer: git-send-email 2.28.0.1011.ga647a8990f-goog Subject: [PATCH v6 07/25] treewide: remove DISABLE_LTO From: Sami Tolvanen To: Masahiro Yamada , Steven Rostedt Cc: Will Deacon , Peter Zijlstra , Greg Kroah-Hartman , "Paul E. McKenney" , Kees Cook , Nick Desaulniers , clang-built-linux@googlegroups.com, kernel-hardening@lists.openwall.com, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, x86@kernel.org, Sami Tolvanen This change removes all instances of DISABLE_LTO from Makefiles, as they are currently unused, and the preferred method of disabling LTO is to filter out the flags instead. Suggested-by: Kees Cook Signed-off-by: Sami Tolvanen Reviewed-by: Kees Cook --- arch/arm64/kernel/vdso/Makefile | 1 - arch/sparc/vdso/Makefile | 2 -- arch/x86/entry/vdso/Makefile | 2 -- kernel/Makefile | 3 --- scripts/Makefile.build | 2 +- 5 files changed, 1 insertion(+), 9 deletions(-) diff --git a/arch/arm64/kernel/vdso/Makefile b/arch/arm64/kernel/vdso/Makefile index 45d5cfe46429..e836e300440f 100644 --- a/arch/arm64/kernel/vdso/Makefile +++ b/arch/arm64/kernel/vdso/Makefile @@ -31,7 +31,6 @@ ccflags-y := -fno-common -fno-builtin -fno-stack-protector -ffixed-x18 ccflags-y += -DDISABLE_BRANCH_PROFILING CFLAGS_REMOVE_vgettimeofday.o = $(CC_FLAGS_FTRACE) -Os $(CC_FLAGS_SCS) $(GCC_PLUGINS_CFLAGS) -KBUILD_CFLAGS += $(DISABLE_LTO) KASAN_SANITIZE := n UBSAN_SANITIZE := n OBJECT_FILES_NON_STANDARD := y diff --git a/arch/sparc/vdso/Makefile b/arch/sparc/vdso/Makefile index f44355e46f31..476c4b315505 100644 --- a/arch/sparc/vdso/Makefile +++ b/arch/sparc/vdso/Makefile @@ -3,8 +3,6 @@ # Building vDSO images for sparc. # -KBUILD_CFLAGS += $(DISABLE_LTO) - VDSO64-$(CONFIG_SPARC64) := y VDSOCOMPAT-$(CONFIG_COMPAT) := y diff --git a/arch/x86/entry/vdso/Makefile b/arch/x86/entry/vdso/Makefile index 215376d975a2..ecc27018ae13 100644 --- a/arch/x86/entry/vdso/Makefile +++ b/arch/x86/entry/vdso/Makefile @@ -9,8 +9,6 @@ ARCH_REL_TYPE_ABS := R_X86_64_JUMP_SLOT|R_X86_64_GLOB_DAT|R_X86_64_RELATIVE| ARCH_REL_TYPE_ABS += R_386_GLOB_DAT|R_386_JMP_SLOT|R_386_RELATIVE include $(srctree)/lib/vdso/Makefile -KBUILD_CFLAGS += $(DISABLE_LTO) - # Sanitizer runtimes are unavailable and cannot be linked here. KASAN_SANITIZE := n UBSAN_SANITIZE := n diff --git a/kernel/Makefile b/kernel/Makefile index 16ec9262ce9d..2561abc91961 100644 --- a/kernel/Makefile +++ b/kernel/Makefile @@ -38,9 +38,6 @@ KASAN_SANITIZE_kcov.o := n KCSAN_SANITIZE_kcov.o := n CFLAGS_kcov.o := $(call cc-option, -fno-conserve-stack) -fno-stack-protector -# cond_syscall is currently not LTO compatible -CFLAGS_sys_ni.o = $(DISABLE_LTO) - obj-y += sched/ obj-y += locking/ obj-y += power/ diff --git a/scripts/Makefile.build b/scripts/Makefile.build index cd4294435fef..6db5b1f55b14 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -111,7 +111,7 @@ endif # --------------------------------------------------------------------------- quiet_cmd_cc_s_c = CC $(quiet_modtag) $@ - cmd_cc_s_c = $(CC) $(filter-out $(DEBUG_CFLAGS), $(c_flags)) $(DISABLE_LTO) -fverbose-asm -S -o $@ $< + cmd_cc_s_c = $(CC) $(filter-out $(DEBUG_CFLAGS), $(c_flags)) -fverbose-asm -S -o $@ $< $(obj)/%.s: $(src)/%.c FORCE $(call if_changed_dep,cc_s_c) From patchwork Tue Oct 13 00:31:46 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sami Tolvanen X-Patchwork-Id: 11834563 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 CC9C992C for ; Tue, 13 Oct 2020 00:33:28 +0000 (UTC) Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.kernel.org (Postfix) with SMTP id CB41321655 for ; Tue, 13 Oct 2020 00:33:27 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="RXU63nRy" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org CB41321655 Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kernel-hardening-return-20181-patchwork-kernel-hardening=patchwork.kernel.org@lists.openwall.com Received: (qmail 13514 invoked by uid 550); 13 Oct 2020 00:32:33 -0000 Mailing-List: contact kernel-hardening-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Delivered-To: mailing list kernel-hardening@lists.openwall.com Received: (qmail 13394 invoked from network); 13 Oct 2020 00:32:32 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=sender:date:in-reply-to:message-id:mime-version:references:subject :from:to:cc; bh=qE83d2elAZP27CB1PRHA3Fr1lT1xa1WkQfnE8zZm1tE=; b=RXU63nRybnD2t8JpGzmXL/DsTM38owNB1K71SQEMpWDTIbxEdoBGrcd288nX4smGZa Xd86odoWA0CTwSUiB19ulAQkfkPn3n3tfy2QGcGNdcPrJPfn6VTUzLpTma5i9+lezfM4 8Cp4VPW1+cXnnYA+8sbqNZuUBjA5jPo3jP5BJ65UMiCbQlngQCfEtwKQmXESVevqv7PK XXtk7NcD/3OhwPT21838KnbbqTi+0+vRJp18ywQBKdifX+bU+IV+864WSm6DOAywvRK+ ZcIdOnGQGcovXiqyYSovpnyjKAQUoKZmqOOXgNPDKXC/WAt922pr39f6jbfJaZUv0XF4 Zc6A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=qE83d2elAZP27CB1PRHA3Fr1lT1xa1WkQfnE8zZm1tE=; b=nQi3DjGsAG3Pp6GEwlEUL+KIE5mAcrmsa7Hh5f6VoxT5infaAFwjfCMP+w4cBd5cxs 8xhCsohGYBLnzoyvjyc03Te2AwqlMaduZC1mujVLAXNmoCEcAYBM5p37wZBuj2qmJFu3 hLSlaK26nxnAw4Poj4yVdSvdBrq4kwz/o6tI3w2o3nFyDO+IO1SBzke667H/UQ1iKCV2 kLpo3srLxpR/uyRETichcorIiimzrrWecH+jucSNVNVzsyHFjTY90OwIYXOXUQXiZ8H/ lc06BTfDwlv0S6HMkUu2dYfFh3Yk2JutIDrxU/VaikIER54vOoHOs7kjNyjVdDCnQCDL /1dw== X-Gm-Message-State: AOAM530PYQGCXOrOP9SQZSzFr7W49QfcdA0GQa3v/tfvqJXFC68LM/qe zlj7AYY7Dc+DkFeSbgsf7wsVWPX9gY6aJLGXj9Q= X-Google-Smtp-Source: ABdhPJw2v/JFZFAKbU/0XDfsQiQVYriog4TU0WgxHiMjW1W8cOtWNUxP6qLYcmbF4aOyAweLKLC7mx7b975rFgY+j+g= Sender: "samitolvanen via sendgmr" X-Received: from samitolvanen1.mtv.corp.google.com ([2620:15c:201:2:f693:9fff:fef4:1b6d]) (user=samitolvanen job=sendgmr) by 2002:a0c:bec4:: with SMTP id f4mr28443151qvj.14.1602549140951; Mon, 12 Oct 2020 17:32:20 -0700 (PDT) Date: Mon, 12 Oct 2020 17:31:46 -0700 In-Reply-To: <20201013003203.4168817-1-samitolvanen@google.com> Message-Id: <20201013003203.4168817-9-samitolvanen@google.com> Mime-Version: 1.0 References: <20201013003203.4168817-1-samitolvanen@google.com> X-Mailer: git-send-email 2.28.0.1011.ga647a8990f-goog Subject: [PATCH v6 08/25] kbuild: add support for Clang LTO From: Sami Tolvanen To: Masahiro Yamada , Steven Rostedt Cc: Will Deacon , Peter Zijlstra , Greg Kroah-Hartman , "Paul E. McKenney" , Kees Cook , Nick Desaulniers , clang-built-linux@googlegroups.com, kernel-hardening@lists.openwall.com, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, x86@kernel.org, Sami Tolvanen This change adds build system support for Clang's Link Time Optimization (LTO). With -flto, instead of ELF object files, Clang produces LLVM bitcode, which is compiled into native code at link time, allowing the final binary to be optimized globally. For more details, see: https://llvm.org/docs/LinkTimeOptimization.html The Kconfig option CONFIG_LTO_CLANG is implemented as a choice, which defaults to LTO being disabled. To use LTO, the architecture must select ARCH_SUPPORTS_LTO_CLANG and support: - compiling with Clang, - compiling inline assembly with Clang's integrated assembler, - and linking with LLD. While using full LTO results in the best runtime performance, the compilation is not scalable in time or memory. CONFIG_THINLTO enables ThinLTO, which allows parallel optimization and faster incremental builds. ThinLTO is used by default if the architecture also selects ARCH_SUPPORTS_THINLTO: https://clang.llvm.org/docs/ThinLTO.html To enable LTO, LLVM tools must be used to handle bitcode files. The easiest way is to pass the LLVM=1 option to make: $ make LLVM=1 defconfig $ scripts/config -e LTO_CLANG $ make LLVM=1 Alternatively, at least the following LLVM tools must be used: CC=clang LD=ld.lld AR=llvm-ar NM=llvm-nm To prepare for LTO support with other compilers, common parts are gated behind the CONFIG_LTO option, and LTO can be disabled for specific files by filtering out CC_FLAGS_LTO. Note that support for DYNAMIC_FTRACE and MODVERSIONS are added in follow-up patches. Signed-off-by: Sami Tolvanen Reviewed-by: Kees Cook --- Makefile | 20 ++++++++- arch/Kconfig | 75 +++++++++++++++++++++++++++++++ include/asm-generic/vmlinux.lds.h | 11 +++-- scripts/Makefile.build | 9 +++- scripts/Makefile.modfinal | 9 +++- scripts/Makefile.modpost | 21 ++++++++- scripts/link-vmlinux.sh | 32 +++++++++---- 7 files changed, 159 insertions(+), 18 deletions(-) diff --git a/Makefile b/Makefile index fda1f8a0b1c7..e91347082163 100644 --- a/Makefile +++ b/Makefile @@ -886,6 +886,21 @@ KBUILD_CFLAGS += $(CC_FLAGS_SCS) export CC_FLAGS_SCS endif +ifdef CONFIG_LTO_CLANG +ifdef CONFIG_THINLTO +CC_FLAGS_LTO += -flto=thin -fsplit-lto-unit +KBUILD_LDFLAGS += --thinlto-cache-dir=$(extmod-prefix).thinlto-cache +else +CC_FLAGS_LTO += -flto +endif +CC_FLAGS_LTO += -fvisibility=default +endif + +ifdef CONFIG_LTO +KBUILD_CFLAGS += $(CC_FLAGS_LTO) +export CC_FLAGS_LTO +endif + ifdef CONFIG_DEBUG_FORCE_FUNCTION_ALIGN_32B KBUILD_CFLAGS += -falign-functions=32 endif @@ -1477,7 +1492,7 @@ MRPROPER_FILES += include/config include/generated \ *.spec # Directories & files removed with 'make distclean' -DISTCLEAN_FILES += tags TAGS cscope* GPATH GTAGS GRTAGS GSYMS +DISTCLEAN_FILES += tags TAGS cscope* GPATH GTAGS GRTAGS GSYMS .thinlto-cache # clean - Delete most, but leave enough to build external modules # @@ -1714,7 +1729,8 @@ _emodinst_post: _emodinst_ $(call cmd,depmod) clean-dirs := $(KBUILD_EXTMOD) -clean: rm-files := $(KBUILD_EXTMOD)/Module.symvers $(KBUILD_EXTMOD)/modules.nsdeps +clean: rm-files := $(KBUILD_EXTMOD)/Module.symvers $(KBUILD_EXTMOD)/modules.nsdeps \ + $(KBUILD_EXTMOD)/.thinlto-cache PHONY += help help: diff --git a/arch/Kconfig b/arch/Kconfig index 76ec3395b843..4ac5dda6d873 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -558,6 +558,81 @@ config SHADOW_CALL_STACK reading and writing arbitrary memory may be able to locate them and hijack control flow by modifying the stacks. +config LTO + bool + +config ARCH_SUPPORTS_LTO_CLANG + bool + help + An architecture should select this option if it supports: + - compiling with Clang, + - compiling inline assembly with Clang's integrated assembler, + - and linking with LLD. + +config ARCH_SUPPORTS_THINLTO + bool + help + An architecture should select this option if it supports Clang's + ThinLTO. + +config THINLTO + bool "Clang ThinLTO" + depends on LTO_CLANG && ARCH_SUPPORTS_THINLTO + default y + help + This option enables Clang's ThinLTO, which allows for parallel + optimization and faster incremental compiles. More information + can be found from Clang's documentation: + + https://clang.llvm.org/docs/ThinLTO.html + + If you say N here, the compiler will use full LTO, which may + produce faster code, but building the kernel will be significantly + slower as the linker won't efficiently utilize multiple threads. + + If unsure, say Y. + +choice + prompt "Link Time Optimization (LTO)" + default LTO_NONE + help + This option enables Link Time Optimization (LTO), which allows the + compiler to optimize binaries globally. + + If unsure, select LTO_NONE. Note that LTO is very resource-intensive + so it's disabled by default. + +config LTO_NONE + bool "None" + +config LTO_CLANG + bool "Clang's Link Time Optimization (EXPERIMENTAL)" + # Clang >= 11: https://github.com/ClangBuiltLinux/linux/issues/510 + depends on CC_IS_CLANG && CLANG_VERSION >= 110000 && LD_IS_LLD + depends on $(success,$(NM) --help | head -n 1 | grep -qi llvm) + depends on $(success,$(AR) --help | head -n 1 | grep -qi llvm) + depends on ARCH_SUPPORTS_LTO_CLANG + depends on !FTRACE_MCOUNT_RECORD + depends on !KASAN + depends on !GCOV_KERNEL + depends on !MODVERSIONS + select LTO + help + This option enables Clang's Link Time Optimization (LTO), which + allows the compiler to optimize the kernel globally. If you enable + this option, the compiler generates LLVM bitcode instead of ELF + object files, and the actual compilation from bitcode happens at + the LTO link step, which may take several minutes depending on the + kernel configuration. More information can be found from LLVM's + documentation: + + https://llvm.org/docs/LinkTimeOptimization.html + + To select this option, you also need to use LLVM tools to handle + the bitcode by passing LLVM=1 to make. + +endchoice + config HAVE_ARCH_WITHIN_STACK_FRAMES bool help diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h index e1843976754a..77e5bd069dd4 100644 --- a/include/asm-generic/vmlinux.lds.h +++ b/include/asm-generic/vmlinux.lds.h @@ -90,15 +90,18 @@ * .data. We don't want to pull in .data..other sections, which Linux * has defined. Same for text and bss. * + * With LTO_CLANG, the linker also splits sections by default, so we need + * these macros to combine the sections during the final link. + * * RODATA_MAIN is not used because existing code already defines .rodata.x * sections to be brought in with rodata. */ -#ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION +#if defined(CONFIG_LD_DEAD_CODE_DATA_ELIMINATION) || defined(CONFIG_LTO_CLANG) #define TEXT_MAIN .text .text.[0-9a-zA-Z_]* -#define DATA_MAIN .data .data.[0-9a-zA-Z_]* .data..LPBX* +#define DATA_MAIN .data .data.[0-9a-zA-Z_]* .data..L* .data..compoundliteral* #define SDATA_MAIN .sdata .sdata.[0-9a-zA-Z_]* -#define RODATA_MAIN .rodata .rodata.[0-9a-zA-Z_]* -#define BSS_MAIN .bss .bss.[0-9a-zA-Z_]* +#define RODATA_MAIN .rodata .rodata.[0-9a-zA-Z_]* .rodata..L* +#define BSS_MAIN .bss .bss.[0-9a-zA-Z_]* .bss..compoundliteral* #define SBSS_MAIN .sbss .sbss.[0-9a-zA-Z_]* #else #define TEXT_MAIN .text diff --git a/scripts/Makefile.build b/scripts/Makefile.build index 6db5b1f55b14..81750ef4a633 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -111,7 +111,7 @@ endif # --------------------------------------------------------------------------- quiet_cmd_cc_s_c = CC $(quiet_modtag) $@ - cmd_cc_s_c = $(CC) $(filter-out $(DEBUG_CFLAGS), $(c_flags)) -fverbose-asm -S -o $@ $< + cmd_cc_s_c = $(CC) $(filter-out $(DEBUG_CFLAGS) $(CC_FLAGS_LTO), $(c_flags)) -fverbose-asm -S -o $@ $< $(obj)/%.s: $(src)/%.c FORCE $(call if_changed_dep,cc_s_c) @@ -428,8 +428,15 @@ $(obj)/lib.a: $(lib-y) FORCE # Do not replace $(filter %.o,^) with $(real-prereqs). When a single object # module is turned into a multi object module, $^ will contain header file # dependencies recorded in the .*.cmd file. +ifdef CONFIG_LTO_CLANG +quiet_cmd_link_multi-m = AR [M] $@ +cmd_link_multi-m = \ + rm -f $@; \ + $(AR) cDPrsT $@ $(filter %.o,$^) +else quiet_cmd_link_multi-m = LD [M] $@ cmd_link_multi-m = $(LD) $(ld_flags) -r -o $@ $(filter %.o,$^) +endif $(multi-used-m): FORCE $(call if_changed,link_multi-m) diff --git a/scripts/Makefile.modfinal b/scripts/Makefile.modfinal index ae01baf96f4e..2cb9a1d88434 100644 --- a/scripts/Makefile.modfinal +++ b/scripts/Makefile.modfinal @@ -6,6 +6,7 @@ PHONY := __modfinal __modfinal: +include $(objtree)/include/config/auto.conf include $(srctree)/scripts/Kbuild.include # for c_flags @@ -29,6 +30,12 @@ quiet_cmd_cc_o_c = CC [M] $@ ARCH_POSTLINK := $(wildcard $(srctree)/arch/$(SRCARCH)/Makefile.postlink) +ifdef CONFIG_LTO_CLANG +# With CONFIG_LTO_CLANG, reuse the object file we compiled for modpost to +# avoid a second slow LTO link +prelink-ext := .lto +endif + quiet_cmd_ld_ko_o = LD [M] $@ cmd_ld_ko_o = \ $(LD) -r $(KBUILD_LDFLAGS) \ @@ -36,7 +43,7 @@ quiet_cmd_ld_ko_o = LD [M] $@ -T scripts/module.lds -o $@ $(filter %.o, $^); \ $(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true) -$(modules): %.ko: %.o %.mod.o scripts/module.lds FORCE +$(modules): %.ko: %$(prelink-ext).o %.mod.o scripts/module.lds FORCE +$(call if_changed,ld_ko_o) targets += $(modules) $(modules:.ko=.mod.o) diff --git a/scripts/Makefile.modpost b/scripts/Makefile.modpost index f54b6ac37ac2..9ff8bfdb574d 100644 --- a/scripts/Makefile.modpost +++ b/scripts/Makefile.modpost @@ -43,6 +43,9 @@ __modpost: include include/config/auto.conf include scripts/Kbuild.include +# for ld_flags +include scripts/Makefile.lib + MODPOST = scripts/mod/modpost \ $(if $(CONFIG_MODVERSIONS),-m) \ $(if $(CONFIG_MODULE_SRCVERSION_ALL),-a) \ @@ -102,12 +105,26 @@ $(input-symdump): @echo >&2 'WARNING: Symbol version dump "$@" is missing.' @echo >&2 ' Modules may not have dependencies or modversions.' +ifdef CONFIG_LTO_CLANG +# With CONFIG_LTO_CLANG, .o files might be LLVM bitcode, so we need to run +# LTO to compile them into native code before running modpost +prelink-ext := .lto + +quiet_cmd_cc_lto_link_modules = LTO [M] $@ +cmd_cc_lto_link_modules = $(LD) $(ld_flags) -r -o $@ --whole-archive $^ + +%.lto.o: %.o + $(call if_changed,cc_lto_link_modules) +endif + +modules := $(sort $(shell cat $(MODORDER))) + # Read out modules.order to pass in modpost. # Otherwise, allmodconfig would fail with "Argument list too long". quiet_cmd_modpost = MODPOST $@ - cmd_modpost = sed 's/ko$$/o/' $< | $(MODPOST) -T - + cmd_modpost = sed 's/\.ko$$/$(prelink-ext)\.o/' $< | $(MODPOST) -T - -$(output-symdump): $(MODORDER) $(input-symdump) FORCE +$(output-symdump): $(MODORDER) $(input-symdump) $(modules:.ko=$(prelink-ext).o) FORCE $(call if_changed,modpost) targets += $(output-symdump) diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh index 372c3719f94c..ebb9f912aab6 100755 --- a/scripts/link-vmlinux.sh +++ b/scripts/link-vmlinux.sh @@ -56,6 +56,14 @@ modpost_link() ${KBUILD_VMLINUX_LIBS} \ --end-group" + if [ -n "${CONFIG_LTO_CLANG}" ]; then + # This might take a while, so indicate that we're doing + # an LTO link + info LTO ${1} + else + info LD ${1} + fi + ${LD} ${KBUILD_LDFLAGS} -r -o ${1} ${objects} } @@ -103,13 +111,22 @@ vmlinux_link() fi if [ "${SRCARCH}" != "um" ]; then - objects="--whole-archive \ - ${KBUILD_VMLINUX_OBJS} \ - --no-whole-archive \ - --start-group \ - ${KBUILD_VMLINUX_LIBS} \ - --end-group \ - ${@}" + if [ -n "${CONFIG_LTO_CLANG}" ]; then + # Use vmlinux.o instead of performing the slow LTO + # link again. + objects="--whole-archive \ + vmlinux.o \ + --no-whole-archive \ + ${@}" + else + objects="--whole-archive \ + ${KBUILD_VMLINUX_OBJS} \ + --no-whole-archive \ + --start-group \ + ${KBUILD_VMLINUX_LIBS} \ + --end-group \ + ${@}" + fi ${LD} ${KBUILD_LDFLAGS} ${LDFLAGS_vmlinux} \ ${strip_debug#-Wl,} \ @@ -274,7 +291,6 @@ fi; ${MAKE} -f "${srctree}/scripts/Makefile.build" obj=init need-builtin=1 #link vmlinux.o -info LD vmlinux.o modpost_link vmlinux.o objtool_link vmlinux.o From patchwork Tue Oct 13 00:31:47 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sami Tolvanen X-Patchwork-Id: 11834567 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 B1A5014D5 for ; Tue, 13 Oct 2020 00:33:39 +0000 (UTC) Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.kernel.org (Postfix) with SMTP id A05DC21655 for ; Tue, 13 Oct 2020 00:33:38 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="hO+ouAmn" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A05DC21655 Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kernel-hardening-return-20182-patchwork-kernel-hardening=patchwork.kernel.org@lists.openwall.com Received: (qmail 13755 invoked by uid 550); 13 Oct 2020 00:32:35 -0000 Mailing-List: contact kernel-hardening-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Delivered-To: mailing list kernel-hardening@lists.openwall.com Received: (qmail 13633 invoked from network); 13 Oct 2020 00:32:34 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=sender:date:in-reply-to:message-id:mime-version:references:subject :from:to:cc; bh=elQ50nEncxP8ueJg68TNJHF0xf9z4qMT6J79emFQEIk=; b=hO+ouAmnxj0Eia3LgSv2Yo2+YGzDS+QNVjXwxLvEsjUf/Abrhf4dCmZ3rUCYGhp4Tw MiCKAh2rFDUZJOcqAFauDHbSbdv+yiXbLzFnhsy0qJcyJM2+c2MJl/jdt69Zbgw6k7Sz 7WVQLVz/kUH3foa41FdryfGZPz6vp/ADiusqVCtj91ugBcq/5fLnBJzH/MptYBjkR32J qe18SzKWG+D3LOMLC6xBHwVKeGau0jXrcO4TjTikbLnPSxFkorWYlH32fG8z2uIQp9b+ 47ivomYnEwHmSxtZevxT+8SfD2hh4jD56SVnaFc1re42RZUMN0Fs4fKGLGk4+eJd1b61 gTaQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=elQ50nEncxP8ueJg68TNJHF0xf9z4qMT6J79emFQEIk=; b=axGMkdL/0h3+jV7j7VKb27bcTikER9ksT++OvabMtu9Ldtu5EyRfCdpX9sxVGGfygX o+xQpmxenzVuEs4b0KQQe/VS0KM7TlbNeUn6E55p772s7Ajwl8xiuXNJxAC7S/OKWWGT sk0RyyT+3gCTddfLbUzOHJGaEdZGXS/iILxuQ9BaHmxsmj1pj+sYmUB/5kaZ1wVZuan/ FkZkWE2C/2922WCprzC0L+QtmjQvpthGlhp6XZQX/d9ndaNzBCGPAZhLk/GYjdd90dTt krSz7qZWytaVBj+kq0+oESzj2K+Q+qE3rq83Ou4F69QUmt4NhdscQL945IMs5mGrAYOk 31Kw== X-Gm-Message-State: AOAM533UHG6PFsFd8Dv3nybD0qs2X0B6QYORK9qVzDbnySCCogfGRC31 f5l2WoftXfMWAn7yvpW38Z3vEjX4e8FfBLY3X1Q= X-Google-Smtp-Source: ABdhPJxpQhMT088r1Uk3I+7jPYoaRFdL9gZyndT977biaTNuihi8CinPeOCY9PkmwrRyimyG+uHdQsu+TCYQhe7i5HI= Sender: "samitolvanen via sendgmr" X-Received: from samitolvanen1.mtv.corp.google.com ([2620:15c:201:2:f693:9fff:fef4:1b6d]) (user=samitolvanen job=sendgmr) by 2002:ad4:5843:: with SMTP id de3mr28374735qvb.12.1602549143066; Mon, 12 Oct 2020 17:32:23 -0700 (PDT) Date: Mon, 12 Oct 2020 17:31:47 -0700 In-Reply-To: <20201013003203.4168817-1-samitolvanen@google.com> Message-Id: <20201013003203.4168817-10-samitolvanen@google.com> Mime-Version: 1.0 References: <20201013003203.4168817-1-samitolvanen@google.com> X-Mailer: git-send-email 2.28.0.1011.ga647a8990f-goog Subject: [PATCH v6 09/25] kbuild: lto: fix module versioning From: Sami Tolvanen To: Masahiro Yamada , Steven Rostedt Cc: Will Deacon , Peter Zijlstra , Greg Kroah-Hartman , "Paul E. McKenney" , Kees Cook , Nick Desaulniers , clang-built-linux@googlegroups.com, kernel-hardening@lists.openwall.com, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, x86@kernel.org, Sami Tolvanen With CONFIG_MODVERSIONS, version information is linked into each compilation unit that exports symbols. With LTO, we cannot use this method as all C code is compiled into LLVM bitcode instead. This change collects symbol versions into .symversions files and merges them in link-vmlinux.sh where they are all linked into vmlinux.o at the same time. Signed-off-by: Sami Tolvanen Reviewed-by: Kees Cook --- .gitignore | 1 + Makefile | 3 ++- arch/Kconfig | 1 - scripts/Makefile.build | 33 +++++++++++++++++++++++++++++++-- scripts/Makefile.modpost | 6 +++++- scripts/link-vmlinux.sh | 23 ++++++++++++++++++++++- 6 files changed, 61 insertions(+), 6 deletions(-) diff --git a/.gitignore b/.gitignore index 162bd2b67bdf..06e76dc39ffe 100644 --- a/.gitignore +++ b/.gitignore @@ -41,6 +41,7 @@ *.so.dbg *.su *.symtypes +*.symversions *.tab.[ch] *.tar *.xz diff --git a/Makefile b/Makefile index e91347082163..91cd6caefa6e 100644 --- a/Makefile +++ b/Makefile @@ -1827,7 +1827,8 @@ clean: $(clean-dirs) -o -name '.tmp_*.o.*' \ -o -name '*.c.[012]*.*' \ -o -name '*.ll' \ - -o -name '*.gcno' \) -type f -print | xargs rm -f + -o -name '*.gcno' \ + -o -name '*.*.symversions' \) -type f -print | xargs rm -f # Generate tags for editors # --------------------------------------------------------------------------- diff --git a/arch/Kconfig b/arch/Kconfig index 4ac5dda6d873..caeb6feb517e 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -615,7 +615,6 @@ config LTO_CLANG depends on !FTRACE_MCOUNT_RECORD depends on !KASAN depends on !GCOV_KERNEL - depends on !MODVERSIONS select LTO help This option enables Clang's Link Time Optimization (LTO), which diff --git a/scripts/Makefile.build b/scripts/Makefile.build index 81750ef4a633..e08e66413dbe 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -166,6 +166,15 @@ ifdef CONFIG_MODVERSIONS # the actual value of the checksum generated by genksyms # o remove .tmp_.o to .o +ifdef CONFIG_LTO_CLANG +# Generate .o.symversions files for each .o with exported symbols, and link these +# to the kernel and/or modules at the end. +cmd_modversions_c = \ + if $(NM) $@ 2>/dev/null | grep -q __ksymtab; then \ + $(call cmd_gensymtypes_c,$(KBUILD_SYMTYPES),$(@:.o=.symtypes)) \ + > $@.symversions; \ + fi; +else cmd_modversions_c = \ if $(OBJDUMP) -h $@ | grep -q __ksymtab; then \ $(call cmd_gensymtypes_c,$(KBUILD_SYMTYPES),$(@:.o=.symtypes)) \ @@ -177,6 +186,7 @@ cmd_modversions_c = \ rm -f $(@D)/.tmp_$(@F:.o=.ver); \ fi endif +endif ifdef CONFIG_FTRACE_MCOUNT_USE_RECORDMCOUNT # compiler will not generate __mcount_loc use recordmcount or recordmcount.pl @@ -393,6 +403,18 @@ $(obj)/%.asn1.c $(obj)/%.asn1.h: $(src)/%.asn1 $(objtree)/scripts/asn1_compiler $(subdir-builtin): $(obj)/%/built-in.a: $(obj)/% ; $(subdir-modorder): $(obj)/%/modules.order: $(obj)/% ; +# combine symversions for later processing +quiet_cmd_update_lto_symversions = SYMVER $@ +ifeq ($(CONFIG_LTO_CLANG) $(CONFIG_MODVERSIONS),y y) + cmd_update_lto_symversions = \ + rm -f $@.symversions \ + $(foreach n, $(filter-out FORCE,$^), \ + $(if $(wildcard $(n).symversions), \ + ; cat $(n).symversions >> $@.symversions)) +else + cmd_update_lto_symversions = echo >/dev/null +endif + # # Rule to compile a set of .o files into one .a file (without symbol table) # @@ -400,8 +422,11 @@ $(subdir-modorder): $(obj)/%/modules.order: $(obj)/% ; quiet_cmd_ar_builtin = AR $@ cmd_ar_builtin = rm -f $@; $(AR) cDPrST $@ $(real-prereqs) +quiet_cmd_ar_and_symver = AR $@ + cmd_ar_and_symver = $(cmd_update_lto_symversions); $(cmd_ar_builtin) + $(obj)/built-in.a: $(real-obj-y) FORCE - $(call if_changed,ar_builtin) + $(call if_changed,ar_and_symver) # # Rule to create modules.order file @@ -421,8 +446,11 @@ $(obj)/modules.order: $(obj-m) FORCE # # Rule to compile a set of .o files into one .a file (with symbol table) # +quiet_cmd_ar_lib = AR $@ + cmd_ar_lib = $(cmd_update_lto_symversions); $(cmd_ar) + $(obj)/lib.a: $(lib-y) FORCE - $(call if_changed,ar) + $(call if_changed,ar_lib) # NOTE: # Do not replace $(filter %.o,^) with $(real-prereqs). When a single object @@ -431,6 +459,7 @@ $(obj)/lib.a: $(lib-y) FORCE ifdef CONFIG_LTO_CLANG quiet_cmd_link_multi-m = AR [M] $@ cmd_link_multi-m = \ + $(cmd_update_lto_symversions); \ rm -f $@; \ $(AR) cDPrsT $@ $(filter %.o,$^) else diff --git a/scripts/Makefile.modpost b/scripts/Makefile.modpost index 9ff8bfdb574d..066beffca09a 100644 --- a/scripts/Makefile.modpost +++ b/scripts/Makefile.modpost @@ -111,7 +111,11 @@ ifdef CONFIG_LTO_CLANG prelink-ext := .lto quiet_cmd_cc_lto_link_modules = LTO [M] $@ -cmd_cc_lto_link_modules = $(LD) $(ld_flags) -r -o $@ --whole-archive $^ +cmd_cc_lto_link_modules = \ + $(LD) $(ld_flags) -r -o $@ \ + $(shell [ -s $(@:.lto.o=.o.symversions) ] && \ + echo -T $(@:.lto.o=.o.symversions)) \ + --whole-archive $^ %.lto.o: %.o $(call if_changed,cc_lto_link_modules) diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh index ebb9f912aab6..1a48ef525f46 100755 --- a/scripts/link-vmlinux.sh +++ b/scripts/link-vmlinux.sh @@ -43,11 +43,26 @@ info() fi } +# If CONFIG_LTO_CLANG is selected, collect generated symbol versions into +# .tmp_symversions.lds +gen_symversions() +{ + info GEN .tmp_symversions.lds + rm -f .tmp_symversions.lds + + for o in ${KBUILD_VMLINUX_OBJS} ${KBUILD_VMLINUX_LIBS}; do + if [ -f ${o}.symversions ]; then + cat ${o}.symversions >> .tmp_symversions.lds + fi + done +} + # Link of vmlinux.o used for section mismatch analysis # ${1} output file modpost_link() { local objects + local lds="" objects="--whole-archive \ ${KBUILD_VMLINUX_OBJS} \ @@ -57,6 +72,11 @@ modpost_link() --end-group" if [ -n "${CONFIG_LTO_CLANG}" ]; then + if [ -n "${CONFIG_MODVERSIONS}" ]; then + gen_symversions + lds="${lds} -T .tmp_symversions.lds" + fi + # This might take a while, so indicate that we're doing # an LTO link info LTO ${1} @@ -64,7 +84,7 @@ modpost_link() info LD ${1} fi - ${LD} ${KBUILD_LDFLAGS} -r -o ${1} ${objects} + ${LD} ${KBUILD_LDFLAGS} -r -o ${1} ${lds} ${objects} } objtool_link() @@ -242,6 +262,7 @@ cleanup() { rm -f .btf.* rm -f .tmp_System.map + rm -f .tmp_symversions.lds rm -f .tmp_vmlinux* rm -f System.map rm -f vmlinux From patchwork Tue Oct 13 00:31:48 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sami Tolvanen X-Patchwork-Id: 11834569 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 F21E992C for ; 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Mon, 12 Oct 2020 17:32:25 -0700 (PDT) Date: Mon, 12 Oct 2020 17:31:48 -0700 In-Reply-To: <20201013003203.4168817-1-samitolvanen@google.com> Message-Id: <20201013003203.4168817-11-samitolvanen@google.com> Mime-Version: 1.0 References: <20201013003203.4168817-1-samitolvanen@google.com> X-Mailer: git-send-email 2.28.0.1011.ga647a8990f-goog Subject: [PATCH v6 10/25] objtool: Split noinstr validation from --vmlinux From: Sami Tolvanen To: Masahiro Yamada , Steven Rostedt Cc: Will Deacon , Peter Zijlstra , Greg Kroah-Hartman , "Paul E. McKenney" , Kees Cook , Nick Desaulniers , clang-built-linux@googlegroups.com, kernel-hardening@lists.openwall.com, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, x86@kernel.org, Sami Tolvanen This change adds a --noinstr flag to objtool to allow us to specify that we're processing vmlinux.o without also enabling noinstr validation. This is needed to avoid false positives with LTO when we run objtool on vmlinux.o without CONFIG_DEBUG_ENTRY. Signed-off-by: Sami Tolvanen --- scripts/link-vmlinux.sh | 2 +- tools/objtool/builtin-check.c | 3 ++- tools/objtool/builtin.h | 2 +- tools/objtool/check.c | 2 +- 4 files changed, 5 insertions(+), 4 deletions(-) diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh index 1a48ef525f46..5ace1dc43993 100755 --- a/scripts/link-vmlinux.sh +++ b/scripts/link-vmlinux.sh @@ -92,7 +92,7 @@ objtool_link() local objtoolopt; if [ -n "${CONFIG_VMLINUX_VALIDATION}" ]; then - objtoolopt="check --vmlinux" + objtoolopt="check --vmlinux --noinstr" if [ -z "${CONFIG_FRAME_POINTER}" ]; then objtoolopt="${objtoolopt} --no-fp" fi diff --git a/tools/objtool/builtin-check.c b/tools/objtool/builtin-check.c index facfc10bc5dc..b84cdc72b51f 100644 --- a/tools/objtool/builtin-check.c +++ b/tools/objtool/builtin-check.c @@ -18,7 +18,7 @@ #include "builtin.h" #include "objtool.h" -bool no_fp, no_unreachable, retpoline, module, backtrace, uaccess, stats, validate_dup, vmlinux, mcount; +bool no_fp, no_unreachable, retpoline, module, backtrace, uaccess, stats, validate_dup, vmlinux, mcount, noinstr; static const char * const check_usage[] = { "objtool check [] file.o", @@ -34,6 +34,7 @@ const struct option check_options[] = { OPT_BOOLEAN('a', "uaccess", &uaccess, "enable uaccess checking"), OPT_BOOLEAN('s', "stats", &stats, "print statistics"), OPT_BOOLEAN('d', "duplicate", &validate_dup, "duplicate validation for vmlinux.o"), + OPT_BOOLEAN('n', "noinstr", &noinstr, "noinstr validation for vmlinux.o"), OPT_BOOLEAN('l', "vmlinux", &vmlinux, "vmlinux.o validation"), OPT_BOOLEAN('M', "mcount", &mcount, "generate __mcount_loc"), OPT_END(), diff --git a/tools/objtool/builtin.h b/tools/objtool/builtin.h index 94565a72b701..2502bb27de17 100644 --- a/tools/objtool/builtin.h +++ b/tools/objtool/builtin.h @@ -8,7 +8,7 @@ #include extern const struct option check_options[]; -extern bool no_fp, no_unreachable, retpoline, module, backtrace, uaccess, stats, validate_dup, vmlinux, mcount; +extern bool no_fp, no_unreachable, retpoline, module, backtrace, uaccess, stats, validate_dup, vmlinux, mcount, noinstr; extern int cmd_check(int argc, const char **argv); extern int cmd_orc(int argc, const char **argv); diff --git a/tools/objtool/check.c b/tools/objtool/check.c index c39c4d2b432a..c216dd4d662c 100644 --- a/tools/objtool/check.c +++ b/tools/objtool/check.c @@ -244,7 +244,7 @@ static void init_insn_state(struct insn_state *state, struct section *sec) * not correctly determine insn->call_dest->sec (external symbols do * not have a section). */ - if (vmlinux && sec) + if (vmlinux && noinstr && sec) state->noinstr = sec->noinstr; } From patchwork Tue Oct 13 00:31:49 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sami Tolvanen X-Patchwork-Id: 11834573 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 1447092C for ; Tue, 13 Oct 2020 00:33:58 +0000 (UTC) Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.kernel.org (Postfix) with SMTP id 31DDF21655 for ; 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Mon, 12 Oct 2020 17:32:27 -0700 (PDT) Date: Mon, 12 Oct 2020 17:31:49 -0700 In-Reply-To: <20201013003203.4168817-1-samitolvanen@google.com> Message-Id: <20201013003203.4168817-12-samitolvanen@google.com> Mime-Version: 1.0 References: <20201013003203.4168817-1-samitolvanen@google.com> X-Mailer: git-send-email 2.28.0.1011.ga647a8990f-goog Subject: [PATCH v6 11/25] kbuild: lto: postpone objtool From: Sami Tolvanen To: Masahiro Yamada , Steven Rostedt Cc: Will Deacon , Peter Zijlstra , Greg Kroah-Hartman , "Paul E. McKenney" , Kees Cook , Nick Desaulniers , clang-built-linux@googlegroups.com, kernel-hardening@lists.openwall.com, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, x86@kernel.org, Sami Tolvanen With LTO, LLVM bitcode won't be compiled into native code until modpost_link, or modfinal for modules. This change postpones calls to objtool until after these steps, and moves objtool_args to Makefile.lib, so the arguments can be reused in Makefile.modfinal. As we didn't have objects to process earlier, we use --duplicate when processing vmlinux.o. This change also disables unreachable instruction warnings with LTO to avoid warnings about the int3 padding between functions. Signed-off-by: Sami Tolvanen Reviewed-by: Kees Cook --- arch/Kconfig | 2 +- scripts/Makefile.build | 22 ++-------------------- scripts/Makefile.lib | 11 +++++++++++ scripts/Makefile.modfinal | 19 ++++++++++++++++--- scripts/link-vmlinux.sh | 28 +++++++++++++++++++++++++--- 5 files changed, 55 insertions(+), 27 deletions(-) diff --git a/arch/Kconfig b/arch/Kconfig index caeb6feb517e..74cbd6e3b116 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -612,7 +612,7 @@ config LTO_CLANG depends on $(success,$(NM) --help | head -n 1 | grep -qi llvm) depends on $(success,$(AR) --help | head -n 1 | grep -qi llvm) depends on ARCH_SUPPORTS_LTO_CLANG - depends on !FTRACE_MCOUNT_RECORD + depends on !FTRACE_MCOUNT_USE_RECORDMCOUNT depends on !KASAN depends on !GCOV_KERNEL select LTO diff --git a/scripts/Makefile.build b/scripts/Makefile.build index e08e66413dbe..ab0ddf4884fd 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -218,30 +218,11 @@ cmd_record_mcount = $(if $(findstring $(strip $(CC_FLAGS_FTRACE)),$(_c_flags)), endif # CONFIG_FTRACE_MCOUNT_USE_RECORDMCOUNT ifdef CONFIG_STACK_VALIDATION +ifndef CONFIG_LTO_CLANG ifneq ($(SKIP_STACK_VALIDATION),1) __objtool_obj := $(objtree)/tools/objtool/objtool -objtool_args = $(if $(CONFIG_UNWINDER_ORC),orc generate,check) - -objtool_args += $(if $(part-of-module), --module,) - -ifndef CONFIG_FRAME_POINTER -objtool_args += --no-fp -endif -ifdef CONFIG_GCOV_KERNEL -objtool_args += --no-unreachable -endif -ifdef CONFIG_RETPOLINE - objtool_args += --retpoline -endif -ifdef CONFIG_X86_SMAP - objtool_args += --uaccess -endif -ifdef CONFIG_FTRACE_MCOUNT_USE_OBJTOOL - objtool_args += --mcount -endif - # 'OBJECT_FILES_NON_STANDARD := y': skip objtool checking for a directory # 'OBJECT_FILES_NON_STANDARD_foo.o := 'y': skip objtool checking for a file # 'OBJECT_FILES_NON_STANDARD_foo.o := 'n': override directory skip for a file @@ -253,6 +234,7 @@ objtool_obj = $(if $(patsubst y%,, \ $(__objtool_obj)) endif # SKIP_STACK_VALIDATION +endif # CONFIG_LTO_CLANG endif # CONFIG_STACK_VALIDATION # Rebuild all objects when objtool changes, or is enabled/disabled. diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib index 3d599716940c..ecb97c9f5feb 100644 --- a/scripts/Makefile.lib +++ b/scripts/Makefile.lib @@ -216,6 +216,17 @@ dtc_cpp_flags = -Wp,-MMD,$(depfile).pre.tmp -nostdinc \ $(addprefix -I,$(DTC_INCLUDE)) \ -undef -D__DTS__ +# Objtool arguments are also needed for modfinal with LTO, so we define +# then here to avoid duplication. +objtool_args = \ + $(if $(CONFIG_UNWINDER_ORC),orc generate,check) \ + $(if $(part-of-module), --module,) \ + $(if $(CONFIG_FRAME_POINTER),, --no-fp) \ + $(if $(CONFIG_GCOV_KERNEL), --no-unreachable,) \ + $(if $(CONFIG_RETPOLINE), --retpoline,) \ + $(if $(CONFIG_X86_SMAP), --uaccess,) \ + $(if $(CONFIG_FTRACE_MCOUNT_USE_OBJTOOL), --mcount,) + # Useful for describing the dependency of composite objects # Usage: # $(call multi_depend, multi_used_targets, suffix_to_remove, suffix_to_add) diff --git a/scripts/Makefile.modfinal b/scripts/Makefile.modfinal index 2cb9a1d88434..1bd2953b11c4 100644 --- a/scripts/Makefile.modfinal +++ b/scripts/Makefile.modfinal @@ -9,7 +9,7 @@ __modfinal: include $(objtree)/include/config/auto.conf include $(srctree)/scripts/Kbuild.include -# for c_flags +# for c_flags and objtool_args include $(srctree)/scripts/Makefile.lib # find all modules listed in modules.order @@ -34,10 +34,23 @@ ifdef CONFIG_LTO_CLANG # With CONFIG_LTO_CLANG, reuse the object file we compiled for modpost to # avoid a second slow LTO link prelink-ext := .lto -endif + +# ELF processing was skipped earlier because we didn't have native code, +# so let's now process the prelinked binary before we link the module. + +ifdef CONFIG_STACK_VALIDATION +ifneq ($(SKIP_STACK_VALIDATION),1) +cmd_ld_ko_o += \ + $(objtree)/tools/objtool/objtool $(objtool_args) \ + $(@:.ko=$(prelink-ext).o); + +endif # SKIP_STACK_VALIDATION +endif # CONFIG_STACK_VALIDATION + +endif # CONFIG_LTO_CLANG quiet_cmd_ld_ko_o = LD [M] $@ - cmd_ld_ko_o = \ + cmd_ld_ko_o += \ $(LD) -r $(KBUILD_LDFLAGS) \ $(KBUILD_LDFLAGS_MODULE) $(LDFLAGS_MODULE) \ -T scripts/module.lds -o $@ $(filter %.o, $^); \ diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh index 5ace1dc43993..7f4d19271180 100755 --- a/scripts/link-vmlinux.sh +++ b/scripts/link-vmlinux.sh @@ -89,14 +89,36 @@ modpost_link() objtool_link() { + local objtoolcmd; local objtoolopt; + if [ "${CONFIG_LTO_CLANG} ${CONFIG_STACK_VALIDATION}" = "y y" ]; then + # Don't perform vmlinux validation unless explicitly requested, + # but run objtool on vmlinux.o now that we have an object file. + if [ -n "${CONFIG_UNWINDER_ORC}" ]; then + objtoolcmd="orc generate" + fi + + objtoolopt="${objtoolopt} --duplicate" + + if [ -n "${CONFIG_FTRACE_MCOUNT_USE_OBJTOOL}" ]; then + objtoolopt="${objtoolopt} --mcount" + fi + fi + if [ -n "${CONFIG_VMLINUX_VALIDATION}" ]; then - objtoolopt="check --vmlinux --noinstr" + objtoolopt="${objtoolopt} --noinstr" + fi + + if [ -n "${objtoolopt}" ]; then + if [ -z "${objtoolcmd}" ]; then + objtoolcmd="check" + fi + objtoolopt="${objtoolopt} --vmlinux" if [ -z "${CONFIG_FRAME_POINTER}" ]; then objtoolopt="${objtoolopt} --no-fp" fi - if [ -n "${CONFIG_GCOV_KERNEL}" ]; then + if [ -n "${CONFIG_GCOV_KERNEL}" ] || [ -n "${CONFIG_LTO_CLANG}" ]; then objtoolopt="${objtoolopt} --no-unreachable" fi if [ -n "${CONFIG_RETPOLINE}" ]; then @@ -106,7 +128,7 @@ objtool_link() objtoolopt="${objtoolopt} --uaccess" fi info OBJTOOL ${1} - tools/objtool/objtool ${objtoolopt} ${1} + tools/objtool/objtool ${objtoolcmd} ${objtoolopt} ${1} fi } From patchwork Tue Oct 13 00:31:50 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sami Tolvanen X-Patchwork-Id: 11834575 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 8155392C for ; 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Mon, 12 Oct 2020 17:32:30 -0700 (PDT) Date: Mon, 12 Oct 2020 17:31:50 -0700 In-Reply-To: <20201013003203.4168817-1-samitolvanen@google.com> Message-Id: <20201013003203.4168817-13-samitolvanen@google.com> Mime-Version: 1.0 References: <20201013003203.4168817-1-samitolvanen@google.com> X-Mailer: git-send-email 2.28.0.1011.ga647a8990f-goog Subject: [PATCH v6 12/25] kbuild: lto: limit inlining From: Sami Tolvanen To: Masahiro Yamada , Steven Rostedt Cc: Will Deacon , Peter Zijlstra , Greg Kroah-Hartman , "Paul E. McKenney" , Kees Cook , Nick Desaulniers , clang-built-linux@googlegroups.com, kernel-hardening@lists.openwall.com, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, x86@kernel.org, Sami Tolvanen This change limits function inlining across translation unit boundaries in order to reduce the binary size with LTO. The -import-instr-limit flag defines a size limit, as the number of LLVM IR instructions, for importing functions from other TUs, defaulting to 100. Based on testing with arm64 defconfig, we found that a limit of 5 is a reasonable compromise between performance and binary size, reducing the size of a stripped vmlinux by 11%. Suggested-by: George Burgess IV Signed-off-by: Sami Tolvanen Reviewed-by: Kees Cook --- Makefile | 3 +++ 1 file changed, 3 insertions(+) diff --git a/Makefile b/Makefile index 91cd6caefa6e..41b01248d400 100644 --- a/Makefile +++ b/Makefile @@ -894,6 +894,9 @@ else CC_FLAGS_LTO += -flto endif CC_FLAGS_LTO += -fvisibility=default + +# Limit inlining across translation units to reduce binary size +KBUILD_LDFLAGS += -mllvm -import-instr-limit=5 endif ifdef CONFIG_LTO From patchwork Tue Oct 13 00:31:51 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sami Tolvanen X-Patchwork-Id: 11834579 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 885F892C for ; Tue, 13 Oct 2020 00:34:16 +0000 (UTC) Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.kernel.org (Postfix) with SMTP id CFA3121655 for ; Tue, 13 Oct 2020 00:34:15 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="RWGnAnvd" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org CFA3121655 Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kernel-hardening-return-20186-patchwork-kernel-hardening=patchwork.kernel.org@lists.openwall.com Received: (qmail 15736 invoked by uid 550); 13 Oct 2020 00:32:45 -0000 Mailing-List: contact kernel-hardening-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Delivered-To: mailing list kernel-hardening@lists.openwall.com Received: (qmail 15637 invoked from network); 13 Oct 2020 00:32:44 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=sender:date:in-reply-to:message-id:mime-version:references:subject :from:to:cc; bh=i0HfMD/wRChzzw+H0j5SIQI+XYlsyfomuEvjB0A2b7U=; b=RWGnAnvd5Lp76tMdFpNH1+zuCs711HvTmjeeqWExWdLO0b+IYvl8hseJy7bQVsA/yQ WbWgdjz9odSgS33tA7SyJrG23HtPbcQQ2sqTeDLN0z+XNW/U1+B04f29pxuTIBAo0Bwr 1kuUI0qew0RRwWEdSqeHxrYPCuM0lKcyAQQHVJyqk0NDK5lndU4kJ0nEntK7Gw/b+6ds NINAxQFY1xV9pWKvIAxegfc8BATcwAptMc23jyb2HlWegaJKMJtRw94gvpud1QRadkKB gA/bzBYbBksOIuoqgqduz/XaFVcQDSEIQm1NvRkC4MArUYBfjsPwupbm8iuKYDaYWWMx dfRw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=i0HfMD/wRChzzw+H0j5SIQI+XYlsyfomuEvjB0A2b7U=; b=gwqfGm7VetomM3Iq4USpKNcgX1XAf20JVy+P2GvMFZXE3v0hPKy8ArMEBphp+af2+1 Am6HoTi9qVtSBBGeBFSaejQ55kOWmerr/wbFwuvDpt3Cr5+jFhuGeR0/YprVlEFRzser yuG7/Z9hgs8CnqnlYgubXBWywiS+loYGPGw4Zfi/HJtrBuGPgJuTbcAkqXQIGw8sC/hf hrUwQ3ieMA9GKYOgOYAdYgXs2DFH8khFbtFqScK0oI5nhnQje/s/fJOqpJbbwCdnZ9HR 4Wwnz7zTET1yeM29mI/9JU8ib6wDq4cAskQ2ACVZheGFiOfOKgO5ZK4JrFnGBxTWGSOC +M6w== X-Gm-Message-State: AOAM531BUE2vT4RqaCJy7h6wjnKGYSiSyGGTHhY4Fj0D6dN1RG7krWSv DLHSbcPCUr61XNBP/FvHHcXaolY0Oi5S88S/8RU= X-Google-Smtp-Source: ABdhPJyWpX0TYRebf3Rkf2Yh1c8ADAskEKEgvpC4cZTbopj2J6pmYFQCkigTg2srbz/p2P1Qt1W0jVbIt5KqdOEhaLA= Sender: "samitolvanen via sendgmr" X-Received: from samitolvanen1.mtv.corp.google.com ([2620:15c:201:2:f693:9fff:fef4:1b6d]) (user=samitolvanen job=sendgmr) by 2002:a25:cc89:: with SMTP id l131mr12649555ybf.154.1602549152704; Mon, 12 Oct 2020 17:32:32 -0700 (PDT) Date: Mon, 12 Oct 2020 17:31:51 -0700 In-Reply-To: <20201013003203.4168817-1-samitolvanen@google.com> Message-Id: <20201013003203.4168817-14-samitolvanen@google.com> Mime-Version: 1.0 References: <20201013003203.4168817-1-samitolvanen@google.com> X-Mailer: git-send-email 2.28.0.1011.ga647a8990f-goog Subject: [PATCH v6 13/25] kbuild: lto: merge module sections From: Sami Tolvanen To: Masahiro Yamada , Steven Rostedt Cc: Will Deacon , Peter Zijlstra , Greg Kroah-Hartman , "Paul E. McKenney" , Kees Cook , Nick Desaulniers , clang-built-linux@googlegroups.com, kernel-hardening@lists.openwall.com, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, x86@kernel.org, Sami Tolvanen LLD always splits sections with LTO, which increases module sizes. This change adds linker script rules to merge the split sections in the final module. Suggested-by: Nick Desaulniers Signed-off-by: Sami Tolvanen Reviewed-by: Kees Cook --- scripts/module.lds.S | 28 ++++++++++++++++++++++++++++ 1 file changed, 28 insertions(+) diff --git a/scripts/module.lds.S b/scripts/module.lds.S index 69b9b71a6a47..037120173a22 100644 --- a/scripts/module.lds.S +++ b/scripts/module.lds.S @@ -25,5 +25,33 @@ SECTIONS { __jump_table 0 : ALIGN(8) { KEEP(*(__jump_table)) } } +#ifdef CONFIG_LTO_CLANG +/* + * With CONFIG_LTO_CLANG, LLD always enables -fdata-sections and + * -ffunction-sections, which increases the size of the final module. + * Merge the split sections in the final binary. + */ +SECTIONS { + __patchable_function_entries : { *(__patchable_function_entries) } + + .bss : { + *(.bss .bss.[0-9a-zA-Z_]*) + *(.bss..L*) + } + + .data : { + *(.data .data.[0-9a-zA-Z_]*) + *(.data..L*) + } + + .rodata : { + *(.rodata .rodata.[0-9a-zA-Z_]*) + *(.rodata..L*) + } + + .text : { *(.text .text.[0-9a-zA-Z_]*) } +} +#endif + /* bring in arch-specific sections */ #include From patchwork Tue Oct 13 00:31:52 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sami Tolvanen X-Patchwork-Id: 11834585 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 C1FD214D5 for ; Tue, 13 Oct 2020 00:34:25 +0000 (UTC) Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.kernel.org (Postfix) with SMTP id 21ED221655 for ; Tue, 13 Oct 2020 00:34:24 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="CfMw3Lf2" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 21ED221655 Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kernel-hardening-return-20187-patchwork-kernel-hardening=patchwork.kernel.org@lists.openwall.com Received: (qmail 16070 invoked by uid 550); 13 Oct 2020 00:32:48 -0000 Mailing-List: contact kernel-hardening-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Delivered-To: mailing list kernel-hardening@lists.openwall.com Received: (qmail 15963 invoked from network); 13 Oct 2020 00:32:47 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=sender:date:in-reply-to:message-id:mime-version:references:subject :from:to:cc; bh=s6lKkOY6jDvHdKU5rddxnOybuTgb4UG6S62YgATiqsw=; b=CfMw3Lf2RqxuH1gK/LplrUVdrli+0+CHSSkm8IVXoxiERluD9UBxqoVgGLYbB0zcGH fcd+f/qjElRp1j6Jdey9Bh7NDBDe4hB9i6yurpQFinDV80y/ezy2gjJtTugW6x9+TxXB lOD7ufXL8OAxIH+6uzRqxS9SQox8gQ5U7CudTH1hC4sfe/ktNYfAhjsreZIIFTMjFG1C RQt8+AhPqYKsAgf3F+x4HsSqm87l4hiDBx+TxXtL+Ap2+aCO42F+hEV40MZGJK2CkBo8 P4FhwGbSHoh+MmiJ53pkyum1T4qHIVaGpa4LSlzx+7mtM5okXCbjhUku3Y3pd0VFE6Pn ksJg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=s6lKkOY6jDvHdKU5rddxnOybuTgb4UG6S62YgATiqsw=; b=nb7iYcSB3s20sJFSsH82nxWiq8Q5EmlJs+m7zPhdYjbv31ckVQorOYCxYeC843KDXR kNnXtfUY1IkA++lBr2gDI1Ag1PGk8tCLFDeSYAYhpug30misS0QGEidcYkye9lmPfdfZ vlAm2pZJO+qJ6oRTWG1rpr3LiiIIQK9GO6NZQLXPw5wRIGKc43TaYBsl6tUZGLUDaZBb +Tq5pwwuxyXkgO38YOuABuvOeNCmzu9pcNmRjrNjvV3GH1jXWOdJ6wIVXBVzLJsXKHxl vfYwqVc9r6nH3Lz1sw+yzrlI/vfC/ZquKlBFLDRgJzYXIgPhlwcIHOCZWPeHIum3Jqa1 DesA== X-Gm-Message-State: AOAM531xmHpOr1gKVwCpRRAE7YOkR6QCkcO9UlLs5iTB2DBQCJGxR5+u SSL00f7FOa0riEvQJ4Fu/RwymRX/selAUfuHO+o= X-Google-Smtp-Source: ABdhPJyFxyU35wX46NP9k8EgBAnMCUQ4LjUrf9Ha6HBecKs6BME4DjIGIM9k+HTmfXPW/UAyVK3X9uWCjK1Lv7DEg7U= Sender: "samitolvanen via sendgmr" X-Received: from samitolvanen1.mtv.corp.google.com ([2620:15c:201:2:f693:9fff:fef4:1b6d]) (user=samitolvanen job=sendgmr) by 2002:aa7:8492:0:b029:155:79b1:437a with SMTP id u18-20020aa784920000b029015579b1437amr18970192pfn.26.1602549155518; Mon, 12 Oct 2020 17:32:35 -0700 (PDT) Date: Mon, 12 Oct 2020 17:31:52 -0700 In-Reply-To: <20201013003203.4168817-1-samitolvanen@google.com> Message-Id: <20201013003203.4168817-15-samitolvanen@google.com> Mime-Version: 1.0 References: <20201013003203.4168817-1-samitolvanen@google.com> X-Mailer: git-send-email 2.28.0.1011.ga647a8990f-goog Subject: [PATCH v6 14/25] kbuild: lto: remove duplicate dependencies from .mod files From: Sami Tolvanen To: Masahiro Yamada , Steven Rostedt Cc: Will Deacon , Peter Zijlstra , Greg Kroah-Hartman , "Paul E. McKenney" , Kees Cook , Nick Desaulniers , clang-built-linux@googlegroups.com, kernel-hardening@lists.openwall.com, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, x86@kernel.org, Sami Tolvanen With LTO, llvm-nm prints out symbols for each archive member separately, which results in a lot of duplicate dependencies in the .mod file when CONFIG_TRIM_UNUSED_SYMS is enabled. When a module consists of several compilation units, the output can exceed the default xargs command size limit and split the dependency list to multiple lines, which results in used symbols getting trimmed. This change removes duplicate dependencies, which will reduce the probability of this happening and makes .mod files smaller and easier to read. Signed-off-by: Sami Tolvanen Reviewed-by: Kees Cook --- scripts/Makefile.build | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/scripts/Makefile.build b/scripts/Makefile.build index ab0ddf4884fd..96d6c9e18901 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -266,7 +266,7 @@ endef # List module undefined symbols (or empty line if not enabled) ifdef CONFIG_TRIM_UNUSED_KSYMS -cmd_undef_syms = $(NM) $< | sed -n 's/^ *U //p' | xargs echo +cmd_undef_syms = $(NM) $< | sed -n 's/^ *U //p' | sort -u | xargs echo else cmd_undef_syms = echo endif From patchwork Tue Oct 13 00:31:53 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sami Tolvanen X-Patchwork-Id: 11834587 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 1285614D5 for ; Tue, 13 Oct 2020 00:34:35 +0000 (UTC) Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.kernel.org (Postfix) with SMTP id 137D321655 for ; Tue, 13 Oct 2020 00:34:33 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="HkPk8tpK" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 137D321655 Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kernel-hardening-return-20188-patchwork-kernel-hardening=patchwork.kernel.org@lists.openwall.com Received: (qmail 16369 invoked by uid 550); 13 Oct 2020 00:32:51 -0000 Mailing-List: contact kernel-hardening-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Delivered-To: mailing list kernel-hardening@lists.openwall.com Received: (qmail 16226 invoked from network); 13 Oct 2020 00:32:50 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=sender:date:in-reply-to:message-id:mime-version:references:subject :from:to:cc; bh=8qK4bJZyQDR87RnO4mGuyFKTVY7cPxnhOBu/7+99VLY=; b=HkPk8tpKW7WNnX/puTQlfRj44UC27N1NhH2tG/YyUiPz4mI9bSOC4Y6B6fSEEEn+IG ElaLzdBOf9b7tZxNWFrEcImnIIH6aSKSkYSToht73sjFdvn+kDlp0b+oKIP6LenxYBWT DKbVWaGk97x1MWhB+s+oGuhH1a5ZllEus6dVqCOlEuDZJTH+dsRVKikqCuLIzzVaNsL9 BCc1skei0i5aLHnUTJbxRQXQ9k0Ogj8Foq09Ag7oTZ/Tx+UgJH+oGlAa2ZKEmbAxkZJZ Ooz89u5G0Q1uQnIADF8Vlg61uMyLhDXZx+rQzbVRWiy9eQohNScX437uj2ZdjCx7eniW MMBQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=8qK4bJZyQDR87RnO4mGuyFKTVY7cPxnhOBu/7+99VLY=; b=ZsfLwH3CVrb9i2KAxA7iwzIPvdWu7KnEgoFVYn23Jpix0u/gD2dXT0el0xrgykBwif oYvjNj8W/JqIWZ/41eNNz8B5xUiiTtH2+Og9JEnlMufKb8gNPZekYVOZJb4Wawu/B1DE /ALTlHe4sI4ZXLuWG7IJtysYIw1pGgGAahVjwsUKddSlosBkTkKmxdbS3UcTcP+E1BNG sMINdmLrzUZQuWohbHN3BGVg2YauKgOc6tLAYSo4Zj8SQRFqWzKc5nskD0rniKErEq2c Y5GccQBhx8cKQtYkGrsoM9CAKKlnhxQr4UqaeNVWFVCwbCB57cSRgEZS64XvX3lcXrZG uMlg== X-Gm-Message-State: AOAM532ZaSZdCUM0SnwgSJ/JP2zC3+a7Mz74J2D5wCrBdXgTd+hbDPRW GgrfgKtxH2tzYkSB9iNkfEev1O4vBdtcQHppmKQ= X-Google-Smtp-Source: ABdhPJzs0fNxnyU0pJ6O0O4KvAY+CnrL+OVeruHaXnFCM0PX2NsfWKm0CCwR1utz9RzO9ELdZrJZ4TqAmm4y8CBBhBU= Sender: "samitolvanen via sendgmr" X-Received: from samitolvanen1.mtv.corp.google.com ([2620:15c:201:2:f693:9fff:fef4:1b6d]) (user=samitolvanen job=sendgmr) by 2002:a25:2bc4:: with SMTP id r187mr36581790ybr.218.1602549158339; Mon, 12 Oct 2020 17:32:38 -0700 (PDT) Date: Mon, 12 Oct 2020 17:31:53 -0700 In-Reply-To: <20201013003203.4168817-1-samitolvanen@google.com> Message-Id: <20201013003203.4168817-16-samitolvanen@google.com> Mime-Version: 1.0 References: <20201013003203.4168817-1-samitolvanen@google.com> X-Mailer: git-send-email 2.28.0.1011.ga647a8990f-goog Subject: [PATCH v6 15/25] init: lto: ensure initcall ordering From: Sami Tolvanen To: Masahiro Yamada , Steven Rostedt Cc: Will Deacon , Peter Zijlstra , Greg Kroah-Hartman , "Paul E. McKenney" , Kees Cook , Nick Desaulniers , clang-built-linux@googlegroups.com, kernel-hardening@lists.openwall.com, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, x86@kernel.org, Sami Tolvanen With LTO, the compiler doesn't necessarily obey the link order for initcalls, and initcall variables need globally unique names to avoid collisions at link time. This change exports __KBUILD_MODNAME and adds the initcall_id() macro, which uses it together with __COUNTER__ and __LINE__ to help ensure these variables have unique names, and moves each variable to its own section when LTO is enabled, so the correct order can be specified using a linker script. The generate_initcall_ordering.pl script uses nm to find initcalls from the object files passed to the linker, and generates a linker script that specifies the same order for initcalls that we would have without LTO. With LTO enabled, the script is called in link-vmlinux.sh through jobserver-exec to limit the number of jobs spawned. Signed-off-by: Sami Tolvanen Reviewed-by: Kees Cook --- include/linux/init.h | 52 +++++- scripts/Makefile.lib | 6 +- scripts/generate_initcall_order.pl | 270 +++++++++++++++++++++++++++++ scripts/link-vmlinux.sh | 15 ++ 4 files changed, 334 insertions(+), 9 deletions(-) create mode 100755 scripts/generate_initcall_order.pl diff --git a/include/linux/init.h b/include/linux/init.h index 212fc9e2f691..af638cd6dd52 100644 --- a/include/linux/init.h +++ b/include/linux/init.h @@ -184,19 +184,57 @@ extern bool initcall_debug; * as KEEP() in the linker script. */ +/* Format: ____ */ +#define __initcall_id(fn) \ + __PASTE(__KBUILD_MODNAME, \ + __PASTE(__, \ + __PASTE(__COUNTER__, \ + __PASTE(_, \ + __PASTE(__LINE__, \ + __PASTE(_, fn)))))) + +/* Format: ____ */ +#define __initcall_name(prefix, __iid, id) \ + __PASTE(__, \ + __PASTE(prefix, \ + __PASTE(__, \ + __PASTE(__iid, id)))) + +#ifdef CONFIG_LTO_CLANG +/* + * With LTO, the compiler doesn't necessarily obey link order for + * initcalls. In order to preserve the correct order, we add each + * variable into its own section and generate a linker script (in + * scripts/link-vmlinux.sh) to specify the order of the sections. + */ +#define __initcall_section(__sec, __iid) \ + #__sec ".init.." #__iid +#else +#define __initcall_section(__sec, __iid) \ + #__sec ".init" +#endif + #ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS -#define ___define_initcall(fn, id, __sec) \ +#define ____define_initcall(fn, __name, __sec) \ __ADDRESSABLE(fn) \ - asm(".section \"" #__sec ".init\", \"a\" \n" \ - "__initcall_" #fn #id ": \n" \ + asm(".section \"" __sec "\", \"a\" \n" \ + __stringify(__name) ": \n" \ ".long " #fn " - . \n" \ ".previous \n"); #else -#define ___define_initcall(fn, id, __sec) \ - static initcall_t __initcall_##fn##id __used \ - __attribute__((__section__(#__sec ".init"))) = fn; +#define ____define_initcall(fn, __name, __sec) \ + static initcall_t __name __used \ + __attribute__((__section__(__sec))) = fn; #endif +#define __unique_initcall(fn, id, __sec, __iid) \ + ____define_initcall(fn, \ + __initcall_name(initcall, __iid, id), \ + __initcall_section(__sec, __iid)) + +#define ___define_initcall(fn, id, __sec) \ + __unique_initcall(fn, id, __sec, __initcall_id(fn)) + #define __define_initcall(fn, id) ___define_initcall(fn, id, .initcall##id) /* @@ -236,7 +274,7 @@ extern bool initcall_debug; #define __exitcall(fn) \ static exitcall_t __exitcall_##fn __exit_call = fn -#define console_initcall(fn) ___define_initcall(fn,, .con_initcall) +#define console_initcall(fn) ___define_initcall(fn, con, .con_initcall) struct obs_kernel_param { const char *str; diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib index ecb97c9f5feb..1142de6a4161 100644 --- a/scripts/Makefile.lib +++ b/scripts/Makefile.lib @@ -117,9 +117,11 @@ target-stem = $(basename $(patsubst $(obj)/%,%,$@)) # These flags are needed for modversions and compiling, so we define them here # $(modname_flags) defines KBUILD_MODNAME as the name of the module it will # end up in (or would, if it gets compiled in) -name-fix = $(call stringify,$(subst $(comma),_,$(subst -,_,$1))) +name-fix-token = $(subst $(comma),_,$(subst -,_,$1)) +name-fix = $(call stringify,$(call name-fix-token,$1)) basename_flags = -DKBUILD_BASENAME=$(call name-fix,$(basetarget)) -modname_flags = -DKBUILD_MODNAME=$(call name-fix,$(modname)) +modname_flags = -DKBUILD_MODNAME=$(call name-fix,$(modname)) \ + -D__KBUILD_MODNAME=kmod_$(call name-fix-token,$(modname)) modfile_flags = -DKBUILD_MODFILE=$(call stringify,$(modfile)) _c_flags = $(filter-out $(CFLAGS_REMOVE_$(target-stem).o), \ diff --git a/scripts/generate_initcall_order.pl b/scripts/generate_initcall_order.pl new file mode 100755 index 000000000000..1a88d3f1b913 --- /dev/null +++ b/scripts/generate_initcall_order.pl @@ -0,0 +1,270 @@ +#!/usr/bin/env perl +# SPDX-License-Identifier: GPL-2.0 +# +# Generates a linker script that specifies the correct initcall order. +# +# Copyright (C) 2019 Google LLC + +use strict; +use warnings; +use IO::Handle; +use IO::Select; +use POSIX ":sys_wait_h"; + +my $nm = $ENV{'NM'} || die "$0: ERROR: NM not set?"; +my $objtree = $ENV{'objtree'} || '.'; + +## currently active child processes +my $jobs = {}; # child process pid -> file handle +## results from child processes +my $results = {}; # object index -> [ { level, secname }, ... ] + +## reads _NPROCESSORS_ONLN to determine the maximum number of processes to +## start +sub get_online_processors { + open(my $fh, "getconf _NPROCESSORS_ONLN 2>/dev/null |") + or die "$0: ERROR: failed to execute getconf: $!"; + my $procs = <$fh>; + close($fh); + + if (!($procs =~ /^\d+$/)) { + return 1; + } + + return int($procs); +} + +## writes results to the parent process +## format: +sub write_results { + my ($index, $initcalls) = @_; + + # sort by the counter value to ensure the order of initcalls within + # each object file is correct + foreach my $counter (sort { $a <=> $b } keys(%{$initcalls})) { + my $level = $initcalls->{$counter}->{'level'}; + + # section name for the initcall function + my $secname = $initcalls->{$counter}->{'module'} . '__' . + $counter . '_' . + $initcalls->{$counter}->{'line'} . '_' . + $initcalls->{$counter}->{'function'}; + + print "$index $level $secname\n"; + } +} + +## reads a result line from a child process and adds it to the $results array +sub read_results{ + my ($fh) = @_; + + # each child prints out a full line w/ autoflush and exits after the + # last line, so even if buffered I/O blocks here, it shouldn't block + # very long + my $data = <$fh>; + + if (!defined($data)) { + return 0; + } + + chomp($data); + + my ($index, $level, $secname) = $data =~ + /^(\d+)\ ([^\ ]+)\ (.*)$/; + + if (!defined($index) || + !defined($level) || + !defined($secname)) { + die "$0: ERROR: child process returned invalid data: $data\n"; + } + + $index = int($index); + + if (!exists($results->{$index})) { + $results->{$index} = []; + } + + push (@{$results->{$index}}, { + 'level' => $level, + 'secname' => $secname + }); + + return 1; +} + +## finds initcalls from an object file or all object files in an archive, and +## writes results back to the parent process +sub find_initcalls { + my ($index, $file) = @_; + + die "$0: ERROR: file $file doesn't exist?" if (! -f $file); + + open(my $fh, "\"$nm\" --defined-only \"$file\" 2>/dev/null |") + or die "$0: ERROR: failed to execute \"$nm\": $!"; + + my $initcalls = {}; + + while (<$fh>) { + chomp; + + # check for the start of a new object file (if processing an + # archive) + my ($path)= $_ =~ /^(.+)\:$/; + + if (defined($path)) { + write_results($index, $initcalls); + $initcalls = {}; + next; + } + + # look for an initcall + my ($module, $counter, $line, $symbol) = $_ =~ + /[a-z]\s+__initcall__(\S*)__(\d+)_(\d+)_(.*)$/; + + if (!defined($module)) { + $module = '' + } + + if (!defined($counter) || + !defined($line) || + !defined($symbol)) { + next; + } + + # parse initcall level + my ($function, $level) = $symbol =~ + /^(.*)((early|rootfs|con|[0-9])s?)$/; + + die "$0: ERROR: invalid initcall name $symbol in $file($path)" + if (!defined($function) || !defined($level)); + + $initcalls->{$counter} = { + 'module' => $module, + 'line' => $line, + 'function' => $function, + 'level' => $level, + }; + } + + close($fh); + write_results($index, $initcalls); +} + +## waits for any child process to complete, reads the results, and adds them to +## the $results array for later processing +sub wait_for_results { + my ($select) = @_; + + my $pid = 0; + do { + # unblock children that may have a full write buffer + foreach my $fh ($select->can_read(0)) { + read_results($fh); + } + + # check for children that have exited, read the remaining data + # from them, and clean up + $pid = waitpid(-1, WNOHANG); + if ($pid > 0) { + if (!exists($jobs->{$pid})) { + next; + } + + my $fh = $jobs->{$pid}; + $select->remove($fh); + + while (read_results($fh)) { + # until eof + } + + close($fh); + delete($jobs->{$pid}); + } + } while ($pid > 0); +} + +## forks a child to process each file passed in the command line and collects +## the results +sub process_files { + my $index = 0; + my $njobs = $ENV{'PARALLELISM'} || get_online_processors(); + my $select = IO::Select->new(); + + while (my $file = shift(@ARGV)) { + # fork a child process and read it's stdout + my $pid = open(my $fh, '-|'); + + if (!defined($pid)) { + die "$0: ERROR: failed to fork: $!"; + } elsif ($pid) { + # save the child process pid and the file handle + $select->add($fh); + $jobs->{$pid} = $fh; + } else { + # in the child process + STDOUT->autoflush(1); + find_initcalls($index, "$objtree/$file"); + exit; + } + + $index++; + + # limit the number of children to $njobs + if (scalar(keys(%{$jobs})) >= $njobs) { + wait_for_results($select); + } + } + + # wait for the remaining children to complete + while (scalar(keys(%{$jobs})) > 0) { + wait_for_results($select); + } +} + +sub generate_initcall_lds() { + process_files(); + + my $sections = {}; # level -> [ secname, ...] + + # sort results to retain link order and split to sections per + # initcall level + foreach my $index (sort { $a <=> $b } keys(%{$results})) { + foreach my $result (@{$results->{$index}}) { + my $level = $result->{'level'}; + + if (!exists($sections->{$level})) { + $sections->{$level} = []; + } + + push(@{$sections->{$level}}, $result->{'secname'}); + } + } + + die "$0: ERROR: no initcalls?" if (!keys(%{$sections})); + + # print out a linker script that defines the order of initcalls for + # each level + print "SECTIONS {\n"; + + foreach my $level (sort(keys(%{$sections}))) { + my $section; + + if ($level eq 'con') { + $section = '.con_initcall.init'; + } else { + $section = ".initcall${level}.init"; + } + + print "\t${section} : {\n"; + + foreach my $secname (@{$sections->{$level}}) { + print "\t\t*(${section}..${secname}) ;\n"; + } + + print "\t}\n"; + } + + print "}\n"; +} + +generate_initcall_lds(); diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh index 7f4d19271180..cd649dc21c04 100755 --- a/scripts/link-vmlinux.sh +++ b/scripts/link-vmlinux.sh @@ -43,6 +43,17 @@ info() fi } +# Generate a linker script to ensure correct ordering of initcalls. +gen_initcalls() +{ + info GEN .tmp_initcalls.lds + + ${PYTHON} ${srctree}/scripts/jobserver-exec \ + ${PERL} ${srctree}/scripts/generate_initcall_order.pl \ + ${KBUILD_VMLINUX_OBJS} ${KBUILD_VMLINUX_LIBS} \ + > .tmp_initcalls.lds +} + # If CONFIG_LTO_CLANG is selected, collect generated symbol versions into # .tmp_symversions.lds gen_symversions() @@ -72,6 +83,9 @@ modpost_link() --end-group" if [ -n "${CONFIG_LTO_CLANG}" ]; then + gen_initcalls + lds="-T .tmp_initcalls.lds" + if [ -n "${CONFIG_MODVERSIONS}" ]; then gen_symversions lds="${lds} -T .tmp_symversions.lds" @@ -284,6 +298,7 @@ cleanup() { rm -f .btf.* rm -f .tmp_System.map + rm -f .tmp_initcalls.lds rm -f .tmp_symversions.lds rm -f .tmp_vmlinux* rm -f System.map From patchwork Tue Oct 13 00:31:54 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sami Tolvanen X-Patchwork-Id: 11834593 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 D8F3592C for ; Tue, 13 Oct 2020 00:34:44 +0000 (UTC) Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.kernel.org (Postfix) with SMTP id 3B1C121655 for ; Tue, 13 Oct 2020 00:34:44 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="oum/rjpL" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3B1C121655 Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kernel-hardening-return-20189-patchwork-kernel-hardening=patchwork.kernel.org@lists.openwall.com Received: (qmail 17628 invoked by uid 550); 13 Oct 2020 00:32:53 -0000 Mailing-List: contact kernel-hardening-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Delivered-To: mailing list kernel-hardening@lists.openwall.com Received: (qmail 17549 invoked from network); 13 Oct 2020 00:32:52 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=sender:date:in-reply-to:message-id:mime-version:references:subject :from:to:cc; bh=ljsItlz/aE0P1FDke8OIPGTsfsgvR6SCQ5aAaAr+FuY=; b=oum/rjpLgBIXRzOc38bbhKmbjYdpUPokaueoFkr6scrVzuU9bSims44TwDZ3YQ5/wo tyFgp4XcVUbaCRTIJ7WyMGcJzX9IUYyY8SHh85axKohx3B9YKTYssK7rD/sd+9Gs6OYS 5pLTO9ddpancYtucgKle3gEvEszXKuKKjECSTrvhHvUa0sTQkJ9oAv6nDZgXB2iqzs6F HaozULUdcqCQOaO/g6JRs136BCvSZm6oYr/J1aF/vZtIWA1niCkH+rLYrArccBedjSyb 5JHkueqtTR75zT9X9nD843dXt6Ntpa7oVvhDLRM/xKFRBTH7orAGCLXgpiwYxg5ODzqW hhPg== X-Google-DKIM-Signature: v=1; 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Mon, 12 Oct 2020 17:32:40 -0700 (PDT) Date: Mon, 12 Oct 2020 17:31:54 -0700 In-Reply-To: <20201013003203.4168817-1-samitolvanen@google.com> Message-Id: <20201013003203.4168817-17-samitolvanen@google.com> Mime-Version: 1.0 References: <20201013003203.4168817-1-samitolvanen@google.com> X-Mailer: git-send-email 2.28.0.1011.ga647a8990f-goog Subject: [PATCH v6 16/25] init: lto: fix PREL32 relocations From: Sami Tolvanen To: Masahiro Yamada , Steven Rostedt Cc: Will Deacon , Peter Zijlstra , Greg Kroah-Hartman , "Paul E. McKenney" , Kees Cook , Nick Desaulniers , clang-built-linux@googlegroups.com, kernel-hardening@lists.openwall.com, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, x86@kernel.org, Sami Tolvanen With LTO, the compiler can rename static functions to avoid global naming collisions. As initcall functions are typically static, renaming can break references to them in inline assembly. This change adds a global stub with a stable name for each initcall to fix the issue when PREL32 relocations are used. Signed-off-by: Sami Tolvanen Reviewed-by: Kees Cook --- include/linux/init.h | 31 +++++++++++++++++++++++++++---- 1 file changed, 27 insertions(+), 4 deletions(-) diff --git a/include/linux/init.h b/include/linux/init.h index af638cd6dd52..cea63f7e7705 100644 --- a/include/linux/init.h +++ b/include/linux/init.h @@ -209,26 +209,49 @@ extern bool initcall_debug; */ #define __initcall_section(__sec, __iid) \ #__sec ".init.." #__iid + +/* + * With LTO, the compiler can rename static functions to avoid + * global naming collisions. We use a global stub function for + * initcalls to create a stable symbol name whose address can be + * taken in inline assembly when PREL32 relocations are used. + */ +#define __initcall_stub(fn, __iid, id) \ + __initcall_name(initstub, __iid, id) + +#define __define_initcall_stub(__stub, fn) \ + int __init __stub(void); \ + int __init __stub(void) \ + { \ + return fn(); \ + } \ + __ADDRESSABLE(__stub) #else #define __initcall_section(__sec, __iid) \ #__sec ".init" + +#define __initcall_stub(fn, __iid, id) fn + +#define __define_initcall_stub(__stub, fn) \ + __ADDRESSABLE(fn) #endif #ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS -#define ____define_initcall(fn, __name, __sec) \ - __ADDRESSABLE(fn) \ +#define ____define_initcall(fn, __stub, __name, __sec) \ + __define_initcall_stub(__stub, fn) \ asm(".section \"" __sec "\", \"a\" \n" \ __stringify(__name) ": \n" \ - ".long " #fn " - . \n" \ + ".long " __stringify(__stub) " - . \n" \ ".previous \n"); #else -#define ____define_initcall(fn, __name, __sec) \ +#define ____define_initcall(fn, __unused, __name, __sec) \ static initcall_t __name __used \ __attribute__((__section__(__sec))) = fn; #endif #define __unique_initcall(fn, id, __sec, __iid) \ ____define_initcall(fn, \ + __initcall_stub(fn, __iid, id), \ __initcall_name(initcall, __iid, id), \ __initcall_section(__sec, __iid)) From patchwork Tue Oct 13 00:31:55 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sami Tolvanen X-Patchwork-Id: 11834595 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 24B4C92C for ; Tue, 13 Oct 2020 00:34:54 +0000 (UTC) Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.kernel.org (Postfix) with SMTP id 77115206B5 for ; Tue, 13 Oct 2020 00:34:53 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="MykYLsVo" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 77115206B5 Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kernel-hardening-return-20190-patchwork-kernel-hardening=patchwork.kernel.org@lists.openwall.com Received: (qmail 17903 invoked by uid 550); 13 Oct 2020 00:32:55 -0000 Mailing-List: contact kernel-hardening-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Delivered-To: mailing list kernel-hardening@lists.openwall.com Received: (qmail 17791 invoked from network); 13 Oct 2020 00:32:54 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=sender:date:in-reply-to:message-id:mime-version:references:subject :from:to:cc; bh=b5rCnYz4obhAgpKHq4mgEn5Hvv5UPGIbAlGkTv5aKg4=; b=MykYLsVoW6bkD+kFLc2l4bZyxZpNnxo5YIENz3yzcHdNClIoPGRyCYicb5g8AQrHlf df0Gi9/JPdft0uy6mxQ8xnHAIiPgUf/18ZfL8+WUyQb/jixQHXBLhPe7l8ku7/iBS+dk mWk3XCOGF5DUG3vDFMYT/uzcvXkm9kiXnlA1gynp2l/H8pHXYSzhOHAKpK0ZbzYicU1P frWYR08lQPhQRINUTpGAlkvjHk+GvfxvYhoX8ZHnGwBsE5Y4RkibJPqELUFCiH0ueFWl 1IdBzaLdFbnfnlmrxckdCqOEsoDhKenpLBG0Q/F1J5BC444cYLDhWDWGR3dyO2Uj2m9+ febQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=b5rCnYz4obhAgpKHq4mgEn5Hvv5UPGIbAlGkTv5aKg4=; b=XHG+5aM1p1qWf5FuXHrk8KS0+ggvMmzAJ9tvAKsdipx72tu2R/hIYvzKDd5HngY90V tv+lURuVhUsMaCyBZRxkUEik3eSqvIDc4cjQ7ynBD57Qtta8t6ublCkUTmk+VE+X4try poP/gTfrOi0bPAfKxcplRCWO8dRUyodOTd3S7oVLj04ledZbx/KAjd9r06Z01zIevz2k WosX2FvqCUEKYb0+Q8SfWeNYdZdK84dz7kA/MTucp7773HzthwZ4djOtGH0YpUIlcXsV 6xLZ93Lp9FJH2Q2dxL91UAdjWBvIPQJl2yjTDKpLdXUsTx8bx0kvkzw8UKZx0MVv2HNG l3Xg== X-Gm-Message-State: AOAM533rDGXHVgQbhgJbc36yUXzyD29d3MBx0bzbvGymxU7udob9CsCP yRyfbIl6D1zAdT5/zlFOakxRsbPN4L8A4rtIR2U= X-Google-Smtp-Source: ABdhPJxj3WaxnTrI4Y+21BRW/jvruhJbF5tMQ4nUmURYi2TvGAs4d/9YZvJC9PHsI7NLcVk286bnvQSZPRgh877RCN0= Sender: "samitolvanen via sendgmr" X-Received: from samitolvanen1.mtv.corp.google.com ([2620:15c:201:2:f693:9fff:fef4:1b6d]) (user=samitolvanen job=sendgmr) by 2002:a25:73c9:: with SMTP id o192mr13193667ybc.353.1602549162840; Mon, 12 Oct 2020 17:32:42 -0700 (PDT) Date: Mon, 12 Oct 2020 17:31:55 -0700 In-Reply-To: <20201013003203.4168817-1-samitolvanen@google.com> Message-Id: <20201013003203.4168817-18-samitolvanen@google.com> Mime-Version: 1.0 References: <20201013003203.4168817-1-samitolvanen@google.com> X-Mailer: git-send-email 2.28.0.1011.ga647a8990f-goog Subject: [PATCH v6 17/25] PCI: Fix PREL32 relocations for LTO From: Sami Tolvanen To: Masahiro Yamada , Steven Rostedt Cc: Will Deacon , Peter Zijlstra , Greg Kroah-Hartman , "Paul E. McKenney" , Kees Cook , Nick Desaulniers , clang-built-linux@googlegroups.com, kernel-hardening@lists.openwall.com, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, x86@kernel.org, Sami Tolvanen With Clang's Link Time Optimization (LTO), the compiler can rename static functions to avoid global naming collisions. As PCI fixup functions are typically static, renaming can break references to them in inline assembly. This change adds a global stub to DECLARE_PCI_FIXUP_SECTION to fix the issue when PREL32 relocations are used. Signed-off-by: Sami Tolvanen Acked-by: Bjorn Helgaas Reviewed-by: Kees Cook --- include/linux/pci.h | 19 ++++++++++++++----- 1 file changed, 14 insertions(+), 5 deletions(-) diff --git a/include/linux/pci.h b/include/linux/pci.h index 835530605c0d..4e64421981c7 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -1909,19 +1909,28 @@ enum pci_fixup_pass { }; #ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS -#define __DECLARE_PCI_FIXUP_SECTION(sec, name, vendor, device, class, \ - class_shift, hook) \ - __ADDRESSABLE(hook) \ +#define ___DECLARE_PCI_FIXUP_SECTION(sec, name, vendor, device, class, \ + class_shift, hook, stub) \ + void stub(struct pci_dev *dev); \ + void stub(struct pci_dev *dev) \ + { \ + hook(dev); \ + } \ asm(".section " #sec ", \"a\" \n" \ ".balign 16 \n" \ ".short " #vendor ", " #device " \n" \ ".long " #class ", " #class_shift " \n" \ - ".long " #hook " - . \n" \ + ".long " #stub " - . \n" \ ".previous \n"); + +#define __DECLARE_PCI_FIXUP_SECTION(sec, name, vendor, device, class, \ + class_shift, hook, stub) \ + ___DECLARE_PCI_FIXUP_SECTION(sec, name, vendor, device, class, \ + class_shift, hook, stub) #define DECLARE_PCI_FIXUP_SECTION(sec, name, vendor, device, class, \ class_shift, hook) \ __DECLARE_PCI_FIXUP_SECTION(sec, name, vendor, device, class, \ - class_shift, hook) + class_shift, hook, __UNIQUE_ID(hook)) #else /* Anonymous variables would be nice... */ #define DECLARE_PCI_FIXUP_SECTION(section, name, vendor, device, class, \ From patchwork Tue Oct 13 00:31:56 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sami Tolvanen X-Patchwork-Id: 11834599 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 4DFD592C for ; Tue, 13 Oct 2020 00:35:03 +0000 (UTC) Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.kernel.org (Postfix) with SMTP id A245E206B5 for ; Tue, 13 Oct 2020 00:35:02 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="CRqhP/uY" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A245E206B5 Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kernel-hardening-return-20191-patchwork-kernel-hardening=patchwork.kernel.org@lists.openwall.com Received: (qmail 18232 invoked by uid 550); 13 Oct 2020 00:32:58 -0000 Mailing-List: contact kernel-hardening-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Delivered-To: mailing list kernel-hardening@lists.openwall.com Received: (qmail 18092 invoked from network); 13 Oct 2020 00:32:57 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=sender:date:in-reply-to:message-id:mime-version:references:subject :from:to:cc; bh=q9NeEgeJtjuDXz46HWaR2aTcr7U+m+G2Xtw7ZYj0i80=; b=CRqhP/uYxJIvrJ7JFPmz8eieDBpzOaZtoHbS8QXp5nwuPeyuXjSGwF+OiqCNfxI5CI f9yeAi6kntV3Hcb0QAvynqG7PhefhCKc+wf5MgUqjtr36fAj0pAt2fao57QEfV3dPubY qGJERG8RZRx1XLbLQX6q3jLoJmOhxxfuFiNcV2xSqDCoRghQrfZVNu4ZAhFk5CS6GT3/ 8Pt5+A54/c+NAPCc64rs9VaZY7zwtEz0DPx7y815vR14O2JTyeWKP0oBmk5RkEWaLa7A 4TZQZriVb4hxzadVvazocXnBKpQ+glS0GUjQz9+czCuxdUNkAumiLnp2/6AngY9hOLxO KvXg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=q9NeEgeJtjuDXz46HWaR2aTcr7U+m+G2Xtw7ZYj0i80=; b=BJ6EeY+a0HGnhM465j0pM58piYor7iAIWShgopKCy77fA1rLnZQd4Z7cjeXZOnC2a/ KHmxqjWe3r73918fyKg0bcmC6O3h44FX3AtUtNpAP4ClJk1aDqvK+MMGRD+L+li7eIjK myb9M4xxvXoQ9NuvfpUhNKJQoIt3sVWK0SWMZzOSv31X50mmHx3zxoyXQ2zwajX4f4D9 Q1/0Q1TFHvY+xBqJ3fANF/WqjkdvdMk8wkW3DkbTwFkSrUt1C5ji99RKMcWpLiDywaF0 ykGck6tWzs5FC+RLQsEA2a6eQT8azKM6GOhoZOvhf0J/zgPmCPaGrRAnABAMkb6hASeD v89Q== X-Gm-Message-State: AOAM530yj3PeqoYkp4l7W89A46D8sSu1fg/VvSDNek6WK3bQokYvXfrM 4WzlTBmZITBI2YMXnX6n8865hBPRgm9zTQ5NJJg= X-Google-Smtp-Source: ABdhPJwNLiDeOTBP4r3W42txfMRPPrerXEwzhxthxcVcHLs0FVIRyeH0/TIJTUqrtTv7hlK+NeLjhdidQu3kmodb/0Q= Sender: "samitolvanen via sendgmr" X-Received: from samitolvanen1.mtv.corp.google.com ([2620:15c:201:2:f693:9fff:fef4:1b6d]) (user=samitolvanen job=sendgmr) by 2002:a0c:c548:: with SMTP id y8mr20871526qvi.41.1602549165345; Mon, 12 Oct 2020 17:32:45 -0700 (PDT) Date: Mon, 12 Oct 2020 17:31:56 -0700 In-Reply-To: <20201013003203.4168817-1-samitolvanen@google.com> Message-Id: <20201013003203.4168817-19-samitolvanen@google.com> Mime-Version: 1.0 References: <20201013003203.4168817-1-samitolvanen@google.com> X-Mailer: git-send-email 2.28.0.1011.ga647a8990f-goog Subject: [PATCH v6 18/25] modpost: lto: strip .lto from module names From: Sami Tolvanen To: Masahiro Yamada , Steven Rostedt Cc: Will Deacon , Peter Zijlstra , Greg Kroah-Hartman , "Paul E. McKenney" , Kees Cook , Nick Desaulniers , clang-built-linux@googlegroups.com, kernel-hardening@lists.openwall.com, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, x86@kernel.org, Sami Tolvanen With LTO, everything is compiled into LLVM bitcode, so we have to link each module into native code before modpost. Kbuild uses the .lto.o suffix for these files, which also ends up in module information. This change strips the unnecessary .lto suffix from the module name. Suggested-by: Bill Wendling Signed-off-by: Sami Tolvanen Reviewed-by: Kees Cook --- scripts/mod/modpost.c | 16 +++++++--------- scripts/mod/modpost.h | 9 +++++++++ scripts/mod/sumversion.c | 6 +++++- 3 files changed, 21 insertions(+), 10 deletions(-) diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c index 69341b36f271..5a329df55cc3 100644 --- a/scripts/mod/modpost.c +++ b/scripts/mod/modpost.c @@ -17,7 +17,6 @@ #include #include #include -#include #include #include "modpost.h" #include "../../include/linux/license.h" @@ -80,14 +79,6 @@ modpost_log(enum loglevel loglevel, const char *fmt, ...) exit(1); } -static inline bool strends(const char *str, const char *postfix) -{ - if (strlen(str) < strlen(postfix)) - return false; - - return strcmp(str + strlen(str) - strlen(postfix), postfix) == 0; -} - void *do_nofail(void *ptr, const char *expr) { if (!ptr) @@ -1984,6 +1975,10 @@ static char *remove_dot(char *s) size_t m = strspn(s + n + 1, "0123456789"); if (m && (s[n + m] == '.' || s[n + m] == 0)) s[n] = 0; + + /* strip trailing .lto */ + if (strends(s, ".lto")) + s[strlen(s) - 4] = '\0'; } return s; } @@ -2007,6 +2002,9 @@ static void read_symbols(const char *modname) /* strip trailing .o */ tmp = NOFAIL(strdup(modname)); tmp[strlen(tmp) - 2] = '\0'; + /* strip trailing .lto */ + if (strends(tmp, ".lto")) + tmp[strlen(tmp) - 4] = '\0'; mod = new_module(tmp); free(tmp); } diff --git a/scripts/mod/modpost.h b/scripts/mod/modpost.h index 3aa052722233..fab30d201f9e 100644 --- a/scripts/mod/modpost.h +++ b/scripts/mod/modpost.h @@ -2,6 +2,7 @@ #include #include #include +#include #include #include #include @@ -180,6 +181,14 @@ static inline unsigned int get_secindex(const struct elf_info *info, return info->symtab_shndx_start[sym - info->symtab_start]; } +static inline bool strends(const char *str, const char *postfix) +{ + if (strlen(str) < strlen(postfix)) + return false; + + return strcmp(str + strlen(str) - strlen(postfix), postfix) == 0; +} + /* file2alias.c */ extern unsigned int cross_build; void handle_moddevtable(struct module *mod, struct elf_info *info, diff --git a/scripts/mod/sumversion.c b/scripts/mod/sumversion.c index d587f40f1117..760e6baa7eda 100644 --- a/scripts/mod/sumversion.c +++ b/scripts/mod/sumversion.c @@ -391,10 +391,14 @@ void get_src_version(const char *modname, char sum[], unsigned sumlen) struct md4_ctx md; char *fname; char filelist[PATH_MAX + 1]; + int postfix_len = 1; + + if (strends(modname, ".lto.o")) + postfix_len = 5; /* objects for a module are listed in the first line of *.mod file. */ snprintf(filelist, sizeof(filelist), "%.*smod", - (int)strlen(modname) - 1, modname); + (int)strlen(modname) - postfix_len, modname); buf = read_text_file(filelist); From patchwork Tue Oct 13 00:31:57 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sami Tolvanen X-Patchwork-Id: 11834601 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 AD39C14D5 for ; Tue, 13 Oct 2020 00:35:12 +0000 (UTC) Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.kernel.org (Postfix) with SMTP id 0EE48206B5 for ; Tue, 13 Oct 2020 00:35:11 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="bb3nDFzI" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0EE48206B5 Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kernel-hardening-return-20192-patchwork-kernel-hardening=patchwork.kernel.org@lists.openwall.com Received: (qmail 19460 invoked by uid 550); 13 Oct 2020 00:33:00 -0000 Mailing-List: contact kernel-hardening-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Delivered-To: mailing list kernel-hardening@lists.openwall.com Received: (qmail 18324 invoked from network); 13 Oct 2020 00:32:59 -0000 DKIM-Signature: v=1; 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Mon, 12 Oct 2020 17:32:47 -0700 (PDT) Date: Mon, 12 Oct 2020 17:31:57 -0700 In-Reply-To: <20201013003203.4168817-1-samitolvanen@google.com> Message-Id: <20201013003203.4168817-20-samitolvanen@google.com> Mime-Version: 1.0 References: <20201013003203.4168817-1-samitolvanen@google.com> X-Mailer: git-send-email 2.28.0.1011.ga647a8990f-goog Subject: [PATCH v6 19/25] scripts/mod: disable LTO for empty.c From: Sami Tolvanen To: Masahiro Yamada , Steven Rostedt Cc: Will Deacon , Peter Zijlstra , Greg Kroah-Hartman , "Paul E. McKenney" , Kees Cook , Nick Desaulniers , clang-built-linux@googlegroups.com, kernel-hardening@lists.openwall.com, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, x86@kernel.org, Sami Tolvanen With CONFIG_LTO_CLANG, clang generates LLVM IR instead of ELF object files. As empty.o is used for probing target properties, disable LTO for it to produce an object file instead. Signed-off-by: Sami Tolvanen Reviewed-by: Kees Cook --- scripts/mod/Makefile | 1 + 1 file changed, 1 insertion(+) diff --git a/scripts/mod/Makefile b/scripts/mod/Makefile index 78071681d924..c9e38ad937fd 100644 --- a/scripts/mod/Makefile +++ b/scripts/mod/Makefile @@ -1,5 +1,6 @@ # SPDX-License-Identifier: GPL-2.0 OBJECT_FILES_NON_STANDARD := y +CFLAGS_REMOVE_empty.o += $(CC_FLAGS_LTO) hostprogs-always-y += modpost mk_elfconfig always-y += empty.o From patchwork Tue Oct 13 00:31:58 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sami Tolvanen X-Patchwork-Id: 11834609 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 87D9114D5 for ; Tue, 13 Oct 2020 00:35:22 +0000 (UTC) Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.kernel.org (Postfix) with SMTP id D896D206B5 for ; Tue, 13 Oct 2020 00:35:21 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="kWr9Y/fq" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D896D206B5 Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kernel-hardening-return-20193-patchwork-kernel-hardening=patchwork.kernel.org@lists.openwall.com Received: (qmail 19768 invoked by uid 550); 13 Oct 2020 00:33:03 -0000 Mailing-List: contact kernel-hardening-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Delivered-To: mailing list kernel-hardening@lists.openwall.com Received: (qmail 19619 invoked from network); 13 Oct 2020 00:33:02 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=sender:date:in-reply-to:message-id:mime-version:references:subject :from:to:cc; bh=IWlwO4V8zfIKj2VoQVJSOpIzEd6XIOwNzizfhzYsm+I=; b=kWr9Y/fqtR1gjXlZbCdcFUO5y9KCbBO6doGSE6eV/R4SdmCC/fG0VIYwLLj+OKBwVo t88hxunzWeAhsqD6nX4pMH3NXEN3LQTEHYiul8l16k+sa2iBaYnnGR+mH9hNA4iikAmL fqVb25yRhuLsNSg7v5YJjN/fVyXPqCbeWKnvoXYnl9WCtRWuKoabyI01wNyG9w6/b7UM 4pHEaQubfMyOEQT05Qht8Nh3XzDQC3RyvotMkxtCaBQJVlkntTJDfU68nv0YNejU3LJ8 DLC87sAOS1Egq4SGIijIlfkUP3DDU2E/gTaUdoloBdFbRBoomS8YvmW0JUlEF9bGUTbb DK5w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=IWlwO4V8zfIKj2VoQVJSOpIzEd6XIOwNzizfhzYsm+I=; b=fSo2Zkr0NrRJk77R6X+utq27CK50Lkrhq4NhVqedP5ahHg1BO9bcK10+Hyd3GvScXH 6DgZDgCxW4eDVeojMXo1dB4iNgq5knJuz6Sa4K6oGUxhx/u/Q1keHvFxdBHRIjq82VhT y3jQmSm5gVyx6cKdKjcBfmaHYZEmBFw8RW6V5nKGS3pXlGYVR9pKC3ViTRHSpu8+pizE vXEOBUHB3HQ3yFSp1QYouNTHZjsfpN4xTWWi4uQ3Zhpvu0xvo3pdaTfn9myhRxjKjqgU sOphbGCr+ZaodVaG5sON7l0n9twcGNzlozvC9N/GVMGKxpYdW+/OLUiBFgq7Dg8dNFp4 8ggA== X-Gm-Message-State: AOAM530NLJFpq2MfjBRaPEny5H18LuytF18RNB7fz5vVua1g2Progs+m SBlyFTiBm7HoztRQmyczKE3HA/wzlzSvI2DHhYQ= X-Google-Smtp-Source: ABdhPJxmlU/A1sroaipRnUbPqUCXYyj5EeYMFDk9TnoZTSUFb4GItjuig8hO655sUorVd0VW8HG+pUfRKD2TGlP3Uv4= Sender: "samitolvanen via sendgmr" X-Received: from samitolvanen1.mtv.corp.google.com ([2620:15c:201:2:f693:9fff:fef4:1b6d]) (user=samitolvanen job=sendgmr) by 2002:ad4:4f46:: with SMTP id eu6mr28230471qvb.9.1602549170292; Mon, 12 Oct 2020 17:32:50 -0700 (PDT) Date: Mon, 12 Oct 2020 17:31:58 -0700 In-Reply-To: <20201013003203.4168817-1-samitolvanen@google.com> Message-Id: <20201013003203.4168817-21-samitolvanen@google.com> Mime-Version: 1.0 References: <20201013003203.4168817-1-samitolvanen@google.com> X-Mailer: git-send-email 2.28.0.1011.ga647a8990f-goog Subject: [PATCH v6 20/25] efi/libstub: disable LTO From: Sami Tolvanen To: Masahiro Yamada , Steven Rostedt Cc: Will Deacon , Peter Zijlstra , Greg Kroah-Hartman , "Paul E. McKenney" , Kees Cook , Nick Desaulniers , clang-built-linux@googlegroups.com, kernel-hardening@lists.openwall.com, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, x86@kernel.org, Sami Tolvanen With CONFIG_LTO_CLANG, we produce LLVM bitcode instead of ELF object files. Since LTO is not really needed here and the Makefile assumes we produce an object file, disable LTO for libstub. Signed-off-by: Sami Tolvanen Reviewed-by: Kees Cook --- drivers/firmware/efi/libstub/Makefile | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/firmware/efi/libstub/Makefile b/drivers/firmware/efi/libstub/Makefile index 0c911e391d75..e927876f3a05 100644 --- a/drivers/firmware/efi/libstub/Makefile +++ b/drivers/firmware/efi/libstub/Makefile @@ -36,6 +36,8 @@ KBUILD_CFLAGS := $(cflags-y) -Os -DDISABLE_BRANCH_PROFILING \ # remove SCS flags from all objects in this directory KBUILD_CFLAGS := $(filter-out $(CC_FLAGS_SCS), $(KBUILD_CFLAGS)) +# disable LTO +KBUILD_CFLAGS := $(filter-out $(CC_FLAGS_LTO), $(KBUILD_CFLAGS)) GCOV_PROFILE := n # Sanitizer runtimes are unavailable and cannot be linked here. From patchwork Tue Oct 13 00:31:59 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sami Tolvanen X-Patchwork-Id: 11834611 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 23C0C92C for ; Tue, 13 Oct 2020 00:35:33 +0000 (UTC) Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.kernel.org (Postfix) with SMTP id 7631321655 for ; Tue, 13 Oct 2020 00:35:32 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="XNjBIDIN" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7631321655 Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kernel-hardening-return-20194-patchwork-kernel-hardening=patchwork.kernel.org@lists.openwall.com Received: (qmail 20002 invoked by uid 550); 13 Oct 2020 00:33:05 -0000 Mailing-List: contact kernel-hardening-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Delivered-To: mailing list kernel-hardening@lists.openwall.com Received: (qmail 19900 invoked from network); 13 Oct 2020 00:33:04 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=sender:date:in-reply-to:message-id:mime-version:references:subject :from:to:cc; bh=BiHYmAAiH626N89XqxkZXfyE7gUyoYuU5gV65m3nGjQ=; b=XNjBIDINKT2pRuTcs85XqtGqpKKB5NK63w4IySiOIysYaLEiPBkXTqBpHa9k0rcANP Mq8luu8tR+/vZGjuz5FWZqlrWlbhD1dsrCW8kjpnk6Of8lm3Uq7bjBxMFSPhYIwpNkRs wzxAjEDJS3JTBUI9Rc9q6CxPrCEE1D+TblGGgUcWZ9InruHmMULIEq8MSFdie4O9SeCJ CDrDZvBBKT7r3ExX0KMrO5Td8OLZ31CYqJR7Va6pe/bqAPf2uWlcxTyzqGmJpNzT0KMv wQ0Tg2BqZiU27oj8+ptgF/4aA8HHcfJ5uqYDxVmwrvDxTkUyV923+xAgmlUuAFczliXV NdAA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=BiHYmAAiH626N89XqxkZXfyE7gUyoYuU5gV65m3nGjQ=; b=ALmqAGm8KClu0dFISzIJtyT6epH3DlxcOuTMvyPDbLn1SJUXTvUBVFPMVJwDyy8ES9 N88fxbTLaKLNdP6VP/bFrECUlPt39r3Pv9OntNEicXA9IjqLsZoMEUVxRp8bKDN3W7Sp xdrP4TwGeaujq9vuTwZX48IeHT2qeUEmUfPlfhJDJHYQ99dxB+BXDdm4Q0y3g6goMW+N vnmEhm7DR8RNiHNmp1rUGtxvTkA9pebhHIQG48vyZ9XfQ9qbjlyER3+IUZsmN1W2VYok 1PBTf71J0xBaYsCLV4GjeumiWJ3wR5n1QPoSznsXfklvtZXEr0oKIrIS/jRmS0UjX1Ou 6/hA== X-Gm-Message-State: AOAM532X7XgJiddhSby0ph24iTrdyL08joEmnmZRYOVudZr7H6fUkZcb mBmR27NtzEpQ81zDolNKPufGjx6gk1xLDpV/dkQ= X-Google-Smtp-Source: ABdhPJw5yrP7SHcc7TWSGYuiAJWigblY6T4KARgQjUPREPTC4jVDZK0jmnjuyAbsgm5fKdwKwlLo7kamaFSoW1+wZMw= Sender: "samitolvanen via sendgmr" X-Received: from samitolvanen1.mtv.corp.google.com ([2620:15c:201:2:f693:9fff:fef4:1b6d]) (user=samitolvanen job=sendgmr) by 2002:ad4:5747:: with SMTP id q7mr15646088qvx.0.1602549172707; Mon, 12 Oct 2020 17:32:52 -0700 (PDT) Date: Mon, 12 Oct 2020 17:31:59 -0700 In-Reply-To: <20201013003203.4168817-1-samitolvanen@google.com> Message-Id: <20201013003203.4168817-22-samitolvanen@google.com> Mime-Version: 1.0 References: <20201013003203.4168817-1-samitolvanen@google.com> X-Mailer: git-send-email 2.28.0.1011.ga647a8990f-goog Subject: [PATCH v6 21/25] drivers/misc/lkdtm: disable LTO for rodata.o From: Sami Tolvanen To: Masahiro Yamada , Steven Rostedt Cc: Will Deacon , Peter Zijlstra , Greg Kroah-Hartman , "Paul E. McKenney" , Kees Cook , Nick Desaulniers , clang-built-linux@googlegroups.com, kernel-hardening@lists.openwall.com, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, x86@kernel.org, Sami Tolvanen Disable LTO for rodata.o to allow objcopy to be used to manipulate sections. Signed-off-by: Sami Tolvanen Acked-by: Kees Cook --- drivers/misc/lkdtm/Makefile | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/misc/lkdtm/Makefile b/drivers/misc/lkdtm/Makefile index c70b3822013f..dd4c936d4d73 100644 --- a/drivers/misc/lkdtm/Makefile +++ b/drivers/misc/lkdtm/Makefile @@ -13,6 +13,7 @@ lkdtm-$(CONFIG_LKDTM) += cfi.o KASAN_SANITIZE_stackleak.o := n KCOV_INSTRUMENT_rodata.o := n +CFLAGS_REMOVE_rodata.o += $(CC_FLAGS_LTO) OBJCOPYFLAGS := OBJCOPYFLAGS_rodata_objcopy.o := \ From patchwork Tue Oct 13 00:32:00 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sami Tolvanen X-Patchwork-Id: 11834613 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 7FD0E1744 for ; Tue, 13 Oct 2020 00:35:42 +0000 (UTC) Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.kernel.org (Postfix) with SMTP id D31F221655 for ; Tue, 13 Oct 2020 00:35:41 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="lfisHSpM" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D31F221655 Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kernel-hardening-return-20195-patchwork-kernel-hardening=patchwork.kernel.org@lists.openwall.com Received: (qmail 20289 invoked by uid 550); 13 Oct 2020 00:33:08 -0000 Mailing-List: contact kernel-hardening-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Delivered-To: mailing list kernel-hardening@lists.openwall.com Received: (qmail 20132 invoked from network); 13 Oct 2020 00:33:06 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=sender:date:in-reply-to:message-id:mime-version:references:subject :from:to:cc; bh=eOx9MhffeJ9wDXWdE5ocpTXQ8u7ymKHm7bpeM0Lggio=; b=lfisHSpMMsM7ePJwI+v7HRtPOXkYDBWSveo+yiAPp2kd+swu/ghhLB9oJY5IHVFqiE F5vc/SkTvuuf0Lgt7JbGpVg8qXwHBHAcLLbVuo/OA0ocXOhsXIisl8SWGlrqNLOaPUaB 7bgQuMqSvZNQ9teX/jTQ1S1vOOH5dOspFSNwJNQ/4Rwu9xyb592VpU0PqUz7lhyZyXvY fnQb15tKz3yfXXclpkb3Y2MSCar9BR1ao21X+EWkaSZ+y6oxMJbI/K+n3io9XZBJTun5 YTbUEoZEzysrkxGQ0gkCfW+/irLace7s6VHMzWPne9EQazh8q3VwnXUwyj8Lws+oHFyQ 0yog== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=eOx9MhffeJ9wDXWdE5ocpTXQ8u7ymKHm7bpeM0Lggio=; b=oiZ2ECqspSdeKTfvS9px2v74r8QRMHxwf2+Q1qDfyysfkevoIGghRWSRDmfTT12umI nFfn01nkspCGMaolqgrfmSVsEuOIPBYWk/4c9++DdxFHGg5edRIFKceu4kCpDSbFlLh4 ApJN8RUmR2wvyK74B/+DZ4Ty+kn6LsxDoBMPMpCjovAaKcW1H7H30nu9w0VqZG/CtNY5 Hif7WDAYPAcIl3Zeg+VcTsCD7viBTt2xJAMck5iL7URj38K3w1yOuUJHE6uW3PH/dZGk 1WNCSWuv0Vbo+7IjBlzb9urOgp0Z2ZmQhRojUadp90X7DHNKH3lackrXaZgDKyqKRsmr gQSg== X-Gm-Message-State: AOAM533DnoBnMFE+fP1qr2z7HV2XYadVQO46/lQcSUKB+3bSB4OtBvvD 4cgUTGolm84hPg6JtKyfB/cCxERR30tMTRhVEv4= X-Google-Smtp-Source: ABdhPJzpop6dxq3bNALNHs53P2n45RdCQq8Qh6KI82XpeuF+GDPsSVikWyxpJ2HCELYpKgptdSzk3Rhv0WYhOvJFT2Q= Sender: "samitolvanen via sendgmr" X-Received: from samitolvanen1.mtv.corp.google.com ([2620:15c:201:2:f693:9fff:fef4:1b6d]) (user=samitolvanen job=sendgmr) by 2002:ad4:4eaf:: with SMTP id ed15mr7416748qvb.40.1602549175140; Mon, 12 Oct 2020 17:32:55 -0700 (PDT) Date: Mon, 12 Oct 2020 17:32:00 -0700 In-Reply-To: <20201013003203.4168817-1-samitolvanen@google.com> Message-Id: <20201013003203.4168817-23-samitolvanen@google.com> Mime-Version: 1.0 References: <20201013003203.4168817-1-samitolvanen@google.com> X-Mailer: git-send-email 2.28.0.1011.ga647a8990f-goog Subject: [PATCH v6 22/25] x86/asm: annotate indirect jumps From: Sami Tolvanen To: Masahiro Yamada , Steven Rostedt Cc: Will Deacon , Peter Zijlstra , Greg Kroah-Hartman , "Paul E. McKenney" , Kees Cook , Nick Desaulniers , clang-built-linux@googlegroups.com, kernel-hardening@lists.openwall.com, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, x86@kernel.org, Sami Tolvanen Running objtool --vmlinux --duplicate on vmlinux.o produces a few warnings about indirect jumps with retpoline: vmlinux.o: warning: objtool: wakeup_long64()+0x61: indirect jump found in RETPOLINE build ... This change adds ANNOTATE_RETPOLINE_SAFE annotations to the jumps in assembly code to stop the warnings. Signed-off-by: Sami Tolvanen Reviewed-by: Kees Cook Reported-by: Sami Tolvanen Signed-off-by: Josh Poimboeuf Tested-by: Sami Tolvanen --- arch/x86/kernel/acpi/wakeup_64.S | 2 ++ arch/x86/platform/pvh/head.S | 2 ++ arch/x86/power/hibernate_asm_64.S | 3 +++ 3 files changed, 7 insertions(+) diff --git a/arch/x86/kernel/acpi/wakeup_64.S b/arch/x86/kernel/acpi/wakeup_64.S index c8daa92f38dc..041e79c4e195 100644 --- a/arch/x86/kernel/acpi/wakeup_64.S +++ b/arch/x86/kernel/acpi/wakeup_64.S @@ -7,6 +7,7 @@ #include #include #include +#include # Copyright 2003 Pavel Machek #include #include +#include #include #include @@ -105,6 +106,7 @@ SYM_CODE_START_LOCAL(pvh_start_xen) /* startup_64 expects boot_params in %rsi. */ mov $_pa(pvh_bootparams), %rsi mov $_pa(startup_64), %rax + ANNOTATE_RETPOLINE_SAFE jmp *%rax #else /* CONFIG_X86_64 */ diff --git a/arch/x86/power/hibernate_asm_64.S b/arch/x86/power/hibernate_asm_64.S index 7918b8415f13..715509d94fa3 100644 --- a/arch/x86/power/hibernate_asm_64.S +++ b/arch/x86/power/hibernate_asm_64.S @@ -21,6 +21,7 @@ #include #include #include +#include SYM_FUNC_START(swsusp_arch_suspend) movq $saved_context, %rax @@ -66,6 +67,7 @@ SYM_CODE_START(restore_image) /* jump to relocated restore code */ movq relocated_restore_code(%rip), %rcx + ANNOTATE_RETPOLINE_SAFE jmpq *%rcx SYM_CODE_END(restore_image) @@ -97,6 +99,7 @@ SYM_CODE_START(core_restore_code) .Ldone: /* jump to the restore_registers address from the image header */ + ANNOTATE_RETPOLINE_SAFE jmpq *%r8 SYM_CODE_END(core_restore_code) From patchwork Tue Oct 13 00:32:01 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sami Tolvanen X-Patchwork-Id: 11834619 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 9DFFA1744 for ; Tue, 13 Oct 2020 00:35:52 +0000 (UTC) Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.kernel.org (Postfix) with SMTP id F2A1221655 for ; Tue, 13 Oct 2020 00:35:51 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="Q8OgoYWJ" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org F2A1221655 Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kernel-hardening-return-20196-patchwork-kernel-hardening=patchwork.kernel.org@lists.openwall.com Received: (qmail 21539 invoked by uid 550); 13 Oct 2020 00:33:10 -0000 Mailing-List: contact kernel-hardening-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Delivered-To: mailing list kernel-hardening@lists.openwall.com Received: (qmail 20422 invoked from network); 13 Oct 2020 00:33:09 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=sender:date:in-reply-to:message-id:mime-version:references:subject :from:to:cc; bh=hXDRuVDCt6QcdhcOoOZPfzkgSyHjAxTz3vM4hOZGaOg=; b=Q8OgoYWJ38A1DTeEf63Hk3c3hYYH4ZF0z/4PTOL57lC91oiRnkf9gd9B9qku6Q1r6u wJpqEn6EAi4UteX1DyN2q/JvaTTtpy84jR6VL0m2JhAl1RoRGIYWTX9l1lTaDfwxSMKw LefJJwRakxdtpPQ08/FQAf92Wa1ozzQh8P2RP2YZPMgSGdz7KcYbVYFd9TUmBqArokGv +ldWe6u3YKRcL8TPbph9eLO/Rzlrbtj3yh/gdxcr/CPwfeRwl+euqw8SSVnfC+RC6cR4 StF7LmGsoqGTDk0I/EG14+cMInf9+wTZSixivfF3ZGh1ldNUWQxtZk/Jwl6sRHt0BJIe TMlQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=hXDRuVDCt6QcdhcOoOZPfzkgSyHjAxTz3vM4hOZGaOg=; b=kxvEGM40iOcnJ0CJ8vO3WoYlTdnuDl74u0IkicRsC8pgwDvKHagnHBmE9wcjeD6hWH iBuqBfCK1ANPiZE762t2YfwI62T3eoipN4oAZrcFBOVrObWAR5lj9LGcHKy9w+ThSwWj zhKgyYCdmCp6f66R631KLJkkzDuJPj3dkiijZSQtSrFFvvhnpDBvFGWnHBcUn4O2SgaY 7yHrK3sociQr0wq/NOfX7X/xYSWF/uqM1Dhr186/rM7+VoACE5yaQlf4iIwkRZy+9iAT uDDcylQ7NG4kHepU7WowOVIGp5bugpVoQMrLjDTHxnpog/HoHS9Y3CKxsLk22i7llzn3 BF+g== X-Gm-Message-State: AOAM533jNvtF7hk0nLRpOqlqqKmOvGeP8UwkcA7y8oZUKzE6US4mizlb omQe0FESpuwXapcPEY0GcIVC3NGdXXVrQEsORB0= X-Google-Smtp-Source: ABdhPJwbnvZ4QCf51zdpzXBwYixY461mQNfzv2AaPBdgQJxvN6CQhpCGMZEflp7FPw1Aa3EKTn0uJBFEhoLOmniOABo= Sender: "samitolvanen via sendgmr" X-Received: from samitolvanen1.mtv.corp.google.com ([2620:15c:201:2:f693:9fff:fef4:1b6d]) (user=samitolvanen job=sendgmr) by 2002:a25:842:: with SMTP id 63mr33820736ybi.311.1602549177444; Mon, 12 Oct 2020 17:32:57 -0700 (PDT) Date: Mon, 12 Oct 2020 17:32:01 -0700 In-Reply-To: <20201013003203.4168817-1-samitolvanen@google.com> Message-Id: <20201013003203.4168817-24-samitolvanen@google.com> Mime-Version: 1.0 References: <20201013003203.4168817-1-samitolvanen@google.com> X-Mailer: git-send-email 2.28.0.1011.ga647a8990f-goog Subject: [PATCH v6 23/25] x86, vdso: disable LTO only for vDSO From: Sami Tolvanen To: Masahiro Yamada , Steven Rostedt Cc: Will Deacon , Peter Zijlstra , Greg Kroah-Hartman , "Paul E. McKenney" , Kees Cook , Nick Desaulniers , clang-built-linux@googlegroups.com, kernel-hardening@lists.openwall.com, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, x86@kernel.org, Sami Tolvanen Disable LTO for the vDSO. Note that while we could use Clang's LTO for the 64-bit vDSO, it won't add noticeable benefit for the small amount of C code. Signed-off-by: Sami Tolvanen Reviewed-by: Kees Cook --- arch/x86/entry/vdso/Makefile | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/arch/x86/entry/vdso/Makefile b/arch/x86/entry/vdso/Makefile index ecc27018ae13..9b742f21d2db 100644 --- a/arch/x86/entry/vdso/Makefile +++ b/arch/x86/entry/vdso/Makefile @@ -90,7 +90,7 @@ ifneq ($(RETPOLINE_VDSO_CFLAGS),) endif endif -$(vobjs): KBUILD_CFLAGS := $(filter-out $(GCC_PLUGINS_CFLAGS) $(RETPOLINE_CFLAGS),$(KBUILD_CFLAGS)) $(CFL) +$(vobjs): KBUILD_CFLAGS := $(filter-out $(CC_FLAGS_LTO) $(GCC_PLUGINS_CFLAGS) $(RETPOLINE_CFLAGS),$(KBUILD_CFLAGS)) $(CFL) # # vDSO code runs in userspace and -pg doesn't help with profiling anyway. @@ -148,6 +148,7 @@ KBUILD_CFLAGS_32 := $(filter-out -fno-pic,$(KBUILD_CFLAGS_32)) KBUILD_CFLAGS_32 := $(filter-out -mfentry,$(KBUILD_CFLAGS_32)) KBUILD_CFLAGS_32 := $(filter-out $(GCC_PLUGINS_CFLAGS),$(KBUILD_CFLAGS_32)) KBUILD_CFLAGS_32 := $(filter-out $(RETPOLINE_CFLAGS),$(KBUILD_CFLAGS_32)) +KBUILD_CFLAGS_32 := $(filter-out $(CC_FLAGS_LTO),$(KBUILD_CFLAGS_32)) KBUILD_CFLAGS_32 += -m32 -msoft-float -mregparm=0 -fpic KBUILD_CFLAGS_32 += -fno-stack-protector KBUILD_CFLAGS_32 += $(call cc-option, -foptimize-sibling-calls) From patchwork Tue Oct 13 00:32:02 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sami Tolvanen X-Patchwork-Id: 11834621 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 859FA174A for ; Tue, 13 Oct 2020 00:36:02 +0000 (UTC) Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.kernel.org (Postfix) with SMTP id D0BCE21655 for ; Tue, 13 Oct 2020 00:36:01 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="UStis3hb" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D0BCE21655 Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kernel-hardening-return-20197-patchwork-kernel-hardening=patchwork.kernel.org@lists.openwall.com Received: (qmail 21793 invoked by uid 550); 13 Oct 2020 00:33:12 -0000 Mailing-List: contact kernel-hardening-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Delivered-To: mailing list kernel-hardening@lists.openwall.com Received: (qmail 21676 invoked from network); 13 Oct 2020 00:33:11 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=sender:date:in-reply-to:message-id:mime-version:references:subject :from:to:cc; bh=s78GraQfKANUm9dTCmVzo29Dpzl6ui3oK0KuklmHT+M=; b=UStis3hbnwPX4GBdlrEziRJNAuXpozGmmfM1jjzsAsE8VSqd0cbY6odMaz39IA0Ojw whXL6/eJ7EeqBedFDwaT3w5Q+1TV0rdJwA3Y3y9puXLwfjf7F0qnCIboZUysC1WDMVid 4Nj43Y1l6hIv3BvqtYvKlA+3y+Qx5yGdBGC7iek7d9zIgRpsjTFpfGg7cM3b7K4jNPc3 C+tUthfv3AI4pSRMqj3k+jNvTZwQ0NPU9oBd39SNZPMR7BGOFp7+kKDm9ZAbYc3IAGak ZWMXtsvozkuOgmM9rpB2qjGh1x8II7JaobE2C/HaxwERoWZW6ZWfuMc4skxi/3WZYGIY 484A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=s78GraQfKANUm9dTCmVzo29Dpzl6ui3oK0KuklmHT+M=; b=CPFkBK5/mcSvhHBcazZAjM2jJl2c7ynXdTZ6+/K2XIO3NiX/8HDGlkfNzpQ24aCQVz XcMWmCKUHdMlIVcd2Fobfs0dKvasz7j/90v2h53qAw/Ef0YOUQeFr4KZL6fMwrpi7zq1 P3xw7RNUopCNebftLCecscLFY0TegJalbmUU3HOnmKjWl+nmyOeLBxo1lJbOXY7Tlqms D4XA9a5IqdaSz4xI4LcK9Jf9eTJJJYVCBuXVg5bXr9ump2UofwajIwl6c7c9H+mrv0+A wlkUAjbbGFDMXMe1ddYVBcVHmTFF0sURa586TgMrR8RTEVyoO6KKoc9qtiKT135fbqZe jVrw== X-Gm-Message-State: AOAM531TBNEOz0tkiY+a+yxYRS3QtcS4sek5AuUk39wrAnhD1Rsi1njf 9DmCBApO8oWJX2fSwSZ1lt+MvUt4gFbPmMhC68U= X-Google-Smtp-Source: ABdhPJys+9GAtwDLSAFaJoF/SaTJzh0YT4ITojDPzI8BvdeCNUSIWeGX02fenqn9RcJYa4C5XTo/mbLq+dmrOimZhu8= Sender: "samitolvanen via sendgmr" X-Received: from samitolvanen1.mtv.corp.google.com ([2620:15c:201:2:f693:9fff:fef4:1b6d]) (user=samitolvanen job=sendgmr) by 2002:a17:902:b40a:b029:d4:e1c7:db59 with SMTP id x10-20020a170902b40ab02900d4e1c7db59mr157311plr.85.1602549179447; Mon, 12 Oct 2020 17:32:59 -0700 (PDT) Date: Mon, 12 Oct 2020 17:32:02 -0700 In-Reply-To: <20201013003203.4168817-1-samitolvanen@google.com> Message-Id: <20201013003203.4168817-25-samitolvanen@google.com> Mime-Version: 1.0 References: <20201013003203.4168817-1-samitolvanen@google.com> X-Mailer: git-send-email 2.28.0.1011.ga647a8990f-goog Subject: [PATCH v6 24/25] x86, cpu: disable LTO for cpu.c From: Sami Tolvanen To: Masahiro Yamada , Steven Rostedt Cc: Will Deacon , Peter Zijlstra , Greg Kroah-Hartman , "Paul E. McKenney" , Kees Cook , Nick Desaulniers , clang-built-linux@googlegroups.com, kernel-hardening@lists.openwall.com, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, x86@kernel.org, Sami Tolvanen Clang incorrectly inlines functions with differing stack protector attributes, which breaks __restore_processor_state() that relies on stack protector being disabled. This change disables LTO for cpu.c to work aroung the bug. Link: https://bugs.llvm.org/show_bug.cgi?id=47479 Suggested-by: Nick Desaulniers Signed-off-by: Sami Tolvanen --- arch/x86/power/Makefile | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/arch/x86/power/Makefile b/arch/x86/power/Makefile index 6907b523e856..5f711a441623 100644 --- a/arch/x86/power/Makefile +++ b/arch/x86/power/Makefile @@ -5,5 +5,9 @@ OBJECT_FILES_NON_STANDARD_hibernate_asm_$(BITS).o := y # itself be stack-protected CFLAGS_cpu.o := -fno-stack-protector +# Clang may incorrectly inline functions with stack protector enabled into +# __restore_processor_state(): https://bugs.llvm.org/show_bug.cgi?id=47479 +CFLAGS_REMOVE_cpu.o := $(CC_FLAGS_LTO) + obj-$(CONFIG_PM_SLEEP) += cpu.o obj-$(CONFIG_HIBERNATION) += hibernate_$(BITS).o hibernate_asm_$(BITS).o hibernate.o From patchwork Tue Oct 13 00:32:03 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sami Tolvanen X-Patchwork-Id: 11834623 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 997C892C for ; Tue, 13 Oct 2020 00:36:12 +0000 (UTC) Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.kernel.org (Postfix) with SMTP id ED21E21655 for ; Tue, 13 Oct 2020 00:36:11 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="H1F377i8" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org ED21E21655 Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kernel-hardening-return-20198-patchwork-kernel-hardening=patchwork.kernel.org@lists.openwall.com Received: (qmail 21965 invoked by uid 550); 13 Oct 2020 00:33:14 -0000 Mailing-List: contact kernel-hardening-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Delivered-To: mailing list kernel-hardening@lists.openwall.com Received: (qmail 21814 invoked from network); 13 Oct 2020 00:33:13 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=sender:date:in-reply-to:message-id:mime-version:references:subject :from:to:cc; bh=NB4DqWz6+fIfMXcokXEeMggmgfFph8OJ/Hk6TSxy9cU=; b=H1F377i8eGQAU/5A0yi1yr0c33hGgdU8XEV9saDmRDeYR0tkVsNxEXUclpv1KfQaU0 /n56cozTapbGtfIzzZr2zkFu0QiAzdA/2U4pijKUqmCNtwJLZOHMOhyYpo/RVj3+a9up uw03RRjDJUEA07AI3ycjej51uqULrxQxMDVvJUyMWGW9h09GHasuDmPYx3/m4etV9s4F /8ifejQyz9wBUEc+H89uj/k7/XI3IN0cqCEm+8nY+wRoA6LNkaf8a9R7Z2OdYi/ddy5V vh/iycwgiqqL8SNRUxcnX4VZEMdDFUCQ+T9Ak4gRDlRzIex36WiXpUQpVsXw+Sm3BVXa op1w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=NB4DqWz6+fIfMXcokXEeMggmgfFph8OJ/Hk6TSxy9cU=; b=Zmcm1aew1rFwK/u8WFGbbqSUkMz1+Oeg6YXkT3NWFBjkDt+gPB6ZiogRIaE4TZBGYH a/0ioePkLe5KlafZMqXQcA7DREcPxih0Dar6Y9PJUj6z8UrTmENXvBUiA9e4XC3ZEGdH RRdqOl7Y3WnTeNhvGRZecZ3SSAV5yyuL/XTNO84JmYw9neBhC8JWTusPr5IYpPH1+hPM NmDdtnLojkSjRURs0XbdivRGe9/DEq6234SSZ+F6MPfvAs2acSsrU9gJ7UmzuB/vzSod EvO5RLkPLMfCXl0XykUjoWf1HWea5jJ/lF7RM0ijJYhTT/oVIz1pUj6qD1kH5EAep4JZ nnRg== X-Gm-Message-State: AOAM530xuHgsm3mYNtc7aEQedDwQ9zxZmPmrfsTSgIT8QKMINCigxZsz ckzWs5bQQWk1PQ/u52/mEAM7PScsQp2xsuLPIbQ= X-Google-Smtp-Source: ABdhPJwqkp+cAjUgpQ/a4zy6+yRRoWJAx7zl3+DhKe/ksIEW9MuPzDjzs69jj4tiiYYaOThbc4htLgXeM88lIlTIveg= Sender: "samitolvanen via sendgmr" X-Received: from samitolvanen1.mtv.corp.google.com ([2620:15c:201:2:f693:9fff:fef4:1b6d]) (user=samitolvanen job=sendgmr) by 2002:ad4:59cf:: with SMTP id el15mr14045430qvb.17.1602549181397; Mon, 12 Oct 2020 17:33:01 -0700 (PDT) Date: Mon, 12 Oct 2020 17:32:03 -0700 In-Reply-To: <20201013003203.4168817-1-samitolvanen@google.com> Message-Id: <20201013003203.4168817-26-samitolvanen@google.com> Mime-Version: 1.0 References: <20201013003203.4168817-1-samitolvanen@google.com> X-Mailer: git-send-email 2.28.0.1011.ga647a8990f-goog Subject: [PATCH v6 25/25] x86, build: allow LTO_CLANG and THINLTO to be selected From: Sami Tolvanen To: Masahiro Yamada , Steven Rostedt Cc: Will Deacon , Peter Zijlstra , Greg Kroah-Hartman , "Paul E. McKenney" , Kees Cook , Nick Desaulniers , clang-built-linux@googlegroups.com, kernel-hardening@lists.openwall.com, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, x86@kernel.org, Sami Tolvanen Pass code model and stack alignment to the linker as these are not stored in LLVM bitcode, and allow both CONFIG_LTO_CLANG and CONFIG_THINLTO to be selected. Signed-off-by: Sami Tolvanen Reviewed-by: Kees Cook --- arch/x86/Kconfig | 2 ++ arch/x86/Makefile | 5 +++++ 2 files changed, 7 insertions(+) diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 6d67646153bc..c579d7000b67 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -92,6 +92,8 @@ config X86 select ARCH_SUPPORTS_ACPI select ARCH_SUPPORTS_ATOMIC_RMW select ARCH_SUPPORTS_NUMA_BALANCING if X86_64 + select ARCH_SUPPORTS_LTO_CLANG if X86_64 + select ARCH_SUPPORTS_THINLTO if X86_64 select ARCH_USE_BUILTIN_BSWAP select ARCH_USE_QUEUED_RWLOCKS select ARCH_USE_QUEUED_SPINLOCKS diff --git a/arch/x86/Makefile b/arch/x86/Makefile index 154259f18b8b..774a7debb27c 100644 --- a/arch/x86/Makefile +++ b/arch/x86/Makefile @@ -173,6 +173,11 @@ ifeq ($(ACCUMULATE_OUTGOING_ARGS), 1) KBUILD_CFLAGS += $(call cc-option,-maccumulate-outgoing-args,) endif +ifdef CONFIG_LTO_CLANG +KBUILD_LDFLAGS += -plugin-opt=-code-model=kernel \ + -plugin-opt=-stack-alignment=$(if $(CONFIG_X86_32),4,8) +endif + # Workaround for a gcc prelease that unfortunately was shipped in a suse release KBUILD_CFLAGS += -Wno-sign-compare #