From patchwork Wed Jan 8 10:32:49 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kevin Brodsky X-Patchwork-Id: 13930520 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 0BC571FC118; Wed, 8 Jan 2025 10:34:53 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1736332495; cv=none; b=Skv325h1c+RG6Gs4+B6gmMLK9H5xFTlEAzaXWcuOdOwOI7Pc9+RMlSz/XkxSlGoVmH6LNRpdoBczVjAcjd1Z8UAVMoPknLotCtqQEGKoSGzBAKrE5KS+vfznB1oDczZcTwq83FYxTqddAMKWZTNpeo6pA6nAIlOiOtZAkCD+ktA= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1736332495; c=relaxed/simple; bh=o4svn+5Fa1eoioikppJPbyVvZH1mHcJe8QRlXXRxZEM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Qq5cUIkUY9wnjwDmFxyuv0QTMiMHRrcLZOouDvvTAT3KuB3KLUiA7NLrrGFo/Lk0z15LUrR6yZZMZ+I1zkC0RX1zz4FZ7pzNwhULjESgI6Nb8zhwr7pqmH6l9n87qLAvs/IgxyHZp9lf3FGmV5emNd9zJ1DOBp0+V5rV7CyNots= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id B77C613D5; Wed, 8 Jan 2025 02:35:21 -0800 (PST) Received: from e123572-lin.arm.com (e123572-lin.cambridge.arm.com [10.1.194.54]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 9D9D73F673; Wed, 8 Jan 2025 02:34:50 -0800 (PST) From: Kevin Brodsky To: linux-hardening@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Kevin Brodsky , Andrew Morton , Mark Brown , Catalin Marinas , Dave Hansen , Jann Horn , Jeff Xu , Joey Gouly , Kees Cook , Linus Walleij , Andy Lutomirski , Marc Zyngier , Peter Zijlstra , Pierre Langlois , Quentin Perret , "Mike Rapoport (IBM)" , Ryan Roberts , Thomas Gleixner , Will Deacon , Matthew Wilcox , Qi Zheng , linux-arm-kernel@lists.infradead.org, x86@kernel.org Subject: [RFC PATCH v2 14/15] arm64: Enable kpkeys_hardened_pgtables support Date: Wed, 8 Jan 2025 10:32:49 +0000 Message-ID: <20250108103250.3188419-15-kevin.brodsky@arm.com> X-Mailer: git-send-email 2.47.0 In-Reply-To: <20250108103250.3188419-1-kevin.brodsky@arm.com> References: <20250108103250.3188419-1-kevin.brodsky@arm.com> Precedence: bulk X-Mailing-List: linux-hardening@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 kpkeys_hardened_pgtables should be enabled as early as possible (if selected). It does however require kpkeys being available, which means on arm64 POE being detected and enabled. POE is a boot feature, so calling kpkeys_hardened_pgtables_enable() just after setup_boot_cpu_features() in smp_prepare_boot_cpu() is the best we can do. With that done, all the bits are in place and we can advertise support for kpkeys_hardened_pgtables by selecting ARCH_HAS_KPKEYS_HARDENED_PGTABLES if ARM64_POE is enabled. Signed-off-by: Kevin Brodsky --- arch/arm64/Kconfig | 1 + arch/arm64/kernel/smp.c | 2 ++ 2 files changed, 3 insertions(+) diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 688ffd9bf503..654e6dff9a79 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -2185,6 +2185,7 @@ config ARM64_POE select ARCH_USES_HIGH_VMA_FLAGS select ARCH_HAS_PKEYS select ARCH_HAS_KPKEYS + select ARCH_HAS_KPKEYS_HARDENED_PGTABLES help The Permission Overlay Extension is used to implement Memory Protection Keys. Memory Protection Keys provides a mechanism for diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c index 3b3f6b56e733..074cab55f9db 100644 --- a/arch/arm64/kernel/smp.c +++ b/arch/arm64/kernel/smp.c @@ -35,6 +35,7 @@ #include #include #include +#include #include #include @@ -468,6 +469,7 @@ void __init smp_prepare_boot_cpu(void) if (system_uses_irq_prio_masking()) init_gic_priority_masking(); + kpkeys_hardened_pgtables_enable(); kasan_init_hw_tags(); /* Init percpu seeds for random tags after cpus are set up. */ kasan_init_sw_tags();