From patchwork Sun Jul 16 21:51:22 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mark Brown X-Patchwork-Id: 13315012 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8144EC001DE for ; Sun, 16 Jul 2023 21:59:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233173AbjGPV7L (ORCPT ); Sun, 16 Jul 2023 17:59:11 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53278 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230366AbjGPV6e (ORCPT ); Sun, 16 Jul 2023 17:58:34 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 101161FDB; Sun, 16 Jul 2023 14:56:19 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id E1A3260ECC; Sun, 16 Jul 2023 21:55:33 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 94855C433CA; Sun, 16 Jul 2023 21:55:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1689544533; bh=pU/Cpaxis09XYO6pS+Tm9irl4OV1fzcTdHAFs+JXaiE=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=rWGbpHGpAPUGRkeHBlxB3u7YFF02VUBqBH3DDfi/zq+uR3bo5c9/02qDMlbROcq1a TOxZq+swTzl/Cn9rsFrq0fkp5SOMZ9rQdBdNmFqBC1WAmool8nFYx21GlscpJIPaX5 Hj4VHZuaIdAexXk06rf4SIr9g7kTQlHiAqUekjYGnvRjB0F6hrvpboYOjI/7sNGzH6 vO0/Sk0ndEyBZ5Xb7JXIentYaOHaqbRU2SiE/17mQ8tYAWW9MdndQvzgrHI+Gte1+R I25r1VajxxALbkW5eIIXj+twrpfKo9XBumj5mL0llLHJuRgO6RoUYB0fbwIFe2mCnI xdT5wxQd/9Vww== From: Mark Brown Date: Sun, 16 Jul 2023 22:51:22 +0100 Subject: [PATCH 26/35] arm64: Add Kconfig for Guarded Control Stack (GCS) MIME-Version: 1.0 Message-Id: <20230716-arm64-gcs-v1-26-bf567f93bba6@kernel.org> References: <20230716-arm64-gcs-v1-0-bf567f93bba6@kernel.org> In-Reply-To: <20230716-arm64-gcs-v1-0-bf567f93bba6@kernel.org> To: Catalin Marinas , Will Deacon , Jonathan Corbet , Andrew Morton , Marc Zyngier , Oliver Upton , James Morse , Suzuki K Poulose , Arnd Bergmann , Oleg Nesterov , Eric Biederman , Kees Cook , Shuah Khan , "Rick P. Edgecombe" , Deepak Gupta , Ard Biesheuvel , Szabolcs Nagy Cc: "H.J. Lu" , Paul Walmsley , Palmer Dabbelt , Albert Ou , linux-arm-kernel@lists.infradead.org, linux-doc@vger.kernel.org, kvmarm@lists.linux.dev, linux-fsdevel@vger.kernel.org, linux-arch@vger.kernel.org, linux-mm@kvack.org, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org, linux-riscv@lists.infradead.org, Mark Brown X-Mailer: b4 0.13-dev-099c9 X-Developer-Signature: v=1; a=openpgp-sha256; l=1333; i=broonie@kernel.org; h=from:subject:message-id; bh=pU/Cpaxis09XYO6pS+Tm9irl4OV1fzcTdHAFs+JXaiE=; b=owEBbQGS/pANAwAKASTWi3JdVIfQAcsmYgBktGajNEQmje9r0OAkZ6IXOyAN5ruAxFmeetfHxjAC LDyTfAyJATMEAAEKAB0WIQSt5miqZ1cYtZ/in+ok1otyXVSH0AUCZLRmowAKCRAk1otyXVSH0JhGB/ 4uEom4k4x+430HQzhyHP2BDhwiv0Xo2K1mTO20ue7Lk8Wti2gS+bFt3j5ucEpMEwtZzUpbv9aFHg8g yVDFSa62TJm4VnlCyDGJgQ8tJrySIzQDdUWaW4NsZkCYMvzaHn7Io9BSwTN7Zseo4HDAFXeuVN+KcI 6W/YOWtqN+FpSOZSkAOtNDCCtHC+Bnwr5v6a6FDSO91/wXPICZ9z5JG71wr/l8ddWrbzhdD+2lp/5O sqSoPHL3zXgrAcCHuCXDKtfj+XAC/YXjHy8TdZgS0bh4tp9AbE5iob7yXE/SpJfC8W3JOO8pyrZA3r LZHn0cmojWthyoDyKu+QYIQJkyHsLU X-Developer-Key: i=broonie@kernel.org; a=openpgp; fpr=3F2568AAC26998F9E813A1C5C3F436CA30F5D8EB Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org Provide a Kconfig option allowing the user to select if GCS support is built into the kernel. Signed-off-by: Mark Brown --- arch/arm64/Kconfig | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 7856c3a3e35a..e1aeeda13c52 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -2091,6 +2091,25 @@ config ARM64_EPAN if the cpu does not implement the feature. endmenu # "ARMv8.7 architectural features" +menu "v9.4 architectural features" + +config ARM64_GCS + bool "Enable support for Guarded Control Stack (GCS)" + default y + select ARCH_USES_HIGH_VMA_FLAGS + help + Guarded Control Stack (GCS) provides support for a separate + stack with restricted access which contains only return + addresses. This can be used to harden against some attacks + by comparing return address used by the program with what is + stored in the GCS, and may also be used to efficiently obtain + the call stack for applications such as profiling. + + The feature is detected at runtime, and will remain disabled + if the system does not implement the feature. + +endmenu # "2022 archiectural features" + config ARM64_SVE bool "ARM Scalable Vector Extension support" default y