From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D92CC35F17D; Fri, 6 Mar 2026 22:56:56 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772837816; cv=none; b=oi2fIBCPm7NU9r01mK8a9Obge4ckV4xRwrOOHaYeJsPflgxbyAlve1vkIIBrBRMZX+iCHlxIO/bVHdRWKif/+u5lEmaOPGEjLD+N+QzCYe53Yk3OG08x2Nw5mBPF3uv9gzhU/CZ4yzCRrd8lGCxS2xaNeyABsCdj4+M0UYrzVw0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772837816; c=relaxed/simple; bh=Z22ghlULx44oqzYfZ0VFpWlMBSswAPSxWRRAMOClw4k=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=KDaR0NENsM9ZUVE7RYThNXI3hxQCK3/SMdznnlmYEx3b760RWXfvzLY4NKGqOqz7Z0nxi/neSJ0Xo0+UOXVlrmw0eNpx9ft1PYz12h23KxAgO+YutRusUew1OMkRwimpvuxlrYdVZ6FdHsnDG8ZAOMM9Mug3q9TZzxG0u2EkKcU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=ctqwQye5; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="ctqwQye5" Received: by smtp.kernel.org (Postfix) with ESMTPSA id B463DC4CEF7; Fri, 6 Mar 2026 22:56:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1772837816; bh=Z22ghlULx44oqzYfZ0VFpWlMBSswAPSxWRRAMOClw4k=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=ctqwQye5tirMLMlcZHWP/msUzGRRcYMTOoMXTj300K9pQMQIBT+yINiB7xXl179o3 /iMofptHLhehAjXDzL6/d18ATABHM17bI+2aLpZslxIUR50vxUDcNmLkGwcU/s9Rzf VgDfE6LI3aRz93CaakBU8wyz0/gY3mOFpY5Xcu1cVd2Hnot7lXwzo/0YyGkZebWJFf zo3KLreu2aKEhid9DfKNkZ7DdiZU9MXVDkYaK3H57jYXnUGYqu+EwyM8te85nRWV1H a05oZxPyxETLpeu7hw5P+FpmjTxRuNt4wG/dmp/v1hE1XDXSXyT89NRC2z3ZTOc7Rb wYLvB7Ti8IdMg== Date: Fri, 6 Mar 2026 15:56:48 -0700 From: Nathan Chancellor To: Arnd Bergmann Cc: Madhavan Srinivasan , Michael Ellerman , Heiko Carstens , Vasily Gorbik , Alexander Gordeev , Arnd Bergmann , Mimi Zohar , Roberto Sassu , Dmitry Kasatkin , Paul Moore , James Morris , "Serge E. Hallyn" , Jarkko Sakkinen , Ard Biesheuvel , Coiby Xu , Nicholas Piggin , "Christophe Leroy (CS GROUP)" , Christian Borntraeger , Sven Schnelle , Eric Snowberg , Nick Desaulniers , Bill Wendling , Justin Stitt , Andrew Donnellan , linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, linux-s390@vger.kernel.org, linux-arch@vger.kernel.org, linux-integrity@vger.kernel.org, linux-security-module@vger.kernel.org, keyrings@vger.kernel.org, llvm@lists.linux.dev Subject: Re: [PATCH] integrity: avoid using __weak functions Message-ID: <20260306225648.GC2746259@ax162> References: <20260306150421.270124-1-arnd@kernel.org> Precedence: bulk X-Mailing-List: linux-integrity@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260306150421.270124-1-arnd@kernel.org> On Fri, Mar 06, 2026 at 04:03:24PM +0100, Arnd Bergmann wrote: > From: Arnd Bergmann > > The security/integrity/secure_boot.c file containing only a __weak function > leads to a build failure with clang: > > Cannot find symbol for section 2: .text. > security/integrity/secure_boot.o: failed > > Moving the function into another file that has at least one non-__weak > symbol would solve this, but this is always fragile. > > Avoid __weak definitions entirely and instead move the stub helper into > an asm-generic header that gets used by default on architectures that > do not provide their own version. This is consistent with how a lot > of other architecture specific functionality works, and is more reliable. > > Fixes: a0f87ede3bf4 ("integrity: Make arch_ima_get_secureboot integrity-wide") > Signed-off-by: Arnd Bergmann > --- > This is a larger change than I had hoped for. > > If you prefer a different way to address the build failure, please > treat this as a Reported-by when you apply your own fix > --- > arch/powerpc/include/asm/secure_boot.h | 6 +++ > arch/powerpc/kernel/secure_boot.c | 1 - > arch/s390/include/asm/secure_boot.h | 9 +++++ > include/asm-generic/Kbuild | 1 + > include/asm-generic/secure_boot.h | 37 +++++++++++++++++++ > include/linux/secure_boot.h | 8 +--- > security/integrity/Makefile | 2 +- > .../integrity/platform_certs/load_powerpc.c | 2 +- > security/integrity/secure_boot.c | 16 -------- > 9 files changed, 56 insertions(+), 26 deletions(-) > create mode 100644 arch/s390/include/asm/secure_boot.h > create mode 100644 include/asm-generic/secure_boot.h > delete mode 100644 security/integrity/secure_boot.c Thanks, I noticed this as well. The version I came up with and have been locally testing is the following, which is a little bit more compact. arch/Kconfig | 3 +++ arch/powerpc/Kconfig | 1 + arch/s390/Kconfig | 1 + arch/s390/kernel/ipl.c | 10 +++++----- include/linux/secure_boot.h | 4 ++++ security/integrity/Makefile | 2 +- security/integrity/secure_boot.c | 16 ---------------- 7 files changed, 15 insertions(+), 22 deletions(-) diff --git a/arch/Kconfig b/arch/Kconfig index 102ddbd4298e..a6d1c8cc1d64 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -1841,4 +1841,7 @@ config ARCH_WANTS_PRE_LINK_VMLINUX config ARCH_HAS_CPU_ATTACK_VECTORS bool +config HAVE_ARCH_GET_SECUREBOOT + def_bool EFI + endmenu diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index c28776660246..e76d6cf0c403 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -1062,6 +1062,7 @@ config PPC_SECURE_BOOT depends on IMA_ARCH_POLICY imply IMA_SECURE_AND_OR_TRUSTED_BOOT select PSERIES_PLPKS if PPC_PSERIES + select HAVE_ARCH_GET_SECUREBOOT help Systems with firmware secure boot enabled need to define security policies to extend secure boot to the OS. This config allows a user diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig index 24695ea29d5b..76f191dd208b 100644 --- a/arch/s390/Kconfig +++ b/arch/s390/Kconfig @@ -181,6 +181,7 @@ config S390 select GENERIC_IOREMAP if PCI select HAVE_ALIGNED_STRUCT_PAGE select HAVE_ARCH_AUDITSYSCALL + select HAVE_ARCH_GET_SECUREBOOT select HAVE_ARCH_JUMP_LABEL select HAVE_ARCH_JUMP_LABEL_RELATIVE select HAVE_ARCH_KASAN diff --git a/arch/s390/kernel/ipl.c b/arch/s390/kernel/ipl.c index 2d01a1713938..3c346b02ceb9 100644 --- a/arch/s390/kernel/ipl.c +++ b/arch/s390/kernel/ipl.c @@ -2388,6 +2388,11 @@ void __no_stack_protector s390_reset_system(void) diag_amode31_ops.diag308_reset(); } +bool arch_get_secureboot(void) +{ + return ipl_secure_flag; +} + #ifdef CONFIG_KEXEC_FILE int ipl_report_add_component(struct ipl_report *report, struct kexec_buf *kbuf, @@ -2505,11 +2510,6 @@ void *ipl_report_finish(struct ipl_report *report) return buf; } -bool arch_get_secureboot(void) -{ - return ipl_secure_flag; -} - int ipl_report_free(struct ipl_report *report) { struct ipl_report_component *comp, *ncomp; diff --git a/include/linux/secure_boot.h b/include/linux/secure_boot.h index 3ded3f03655c..d17e92351567 100644 --- a/include/linux/secure_boot.h +++ b/include/linux/secure_boot.h @@ -10,10 +10,14 @@ #include +#ifdef CONFIG_HAVE_ARCH_GET_SECUREBOOT /* * Returns true if the platform secure boot is enabled. * Returns false if disabled or not supported. */ bool arch_get_secureboot(void); +#else +static inline bool arch_get_secureboot(void) { return false; } +#endif #endif /* _LINUX_SECURE_BOOT_H */ diff --git a/security/integrity/Makefile b/security/integrity/Makefile index 548665e2b702..45dfdedbdad4 100644 --- a/security/integrity/Makefile +++ b/security/integrity/Makefile @@ -5,7 +5,7 @@ obj-$(CONFIG_INTEGRITY) += integrity.o -integrity-y := iint.o secure_boot.o +integrity-y := iint.o integrity-$(CONFIG_INTEGRITY_AUDIT) += integrity_audit.o integrity-$(CONFIG_INTEGRITY_SIGNATURE) += digsig.o integrity-$(CONFIG_INTEGRITY_ASYMMETRIC_KEYS) += digsig_asymmetric.o diff --git a/security/integrity/secure_boot.c b/security/integrity/secure_boot.c deleted file mode 100644 index fc2693c286f8..000000000000 --- a/security/integrity/secure_boot.c +++ /dev/null @@ -1,16 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0-only -/* - * Copyright (C) 2026 Red Hat, Inc. All Rights Reserved. - * - * Author: Coiby Xu - */ -#include - -/* - * Default weak implementation. - * Architectures that support secure boot must override this. - */ -__weak bool arch_get_secureboot(void) -{ - return false; -}