From patchwork Mon Aug 7 22:00:14 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mark Brown X-Patchwork-Id: 13345107 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 58A20C04A94 for ; Mon, 7 Aug 2023 22:03:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231211AbjHGWDf (ORCPT ); Mon, 7 Aug 2023 18:03:35 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42742 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231236AbjHGWC6 (ORCPT ); Mon, 7 Aug 2023 18:02:58 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D2C992136; Mon, 7 Aug 2023 15:02:28 -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 AEDDF622A3; Mon, 7 Aug 2023 22:02:27 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 61D44C433B6; Mon, 7 Aug 2023 22:02:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1691445747; bh=BgZhQzy1ZDJ87SbUj0QMsK2M0tcAHYl7N7+4HCzYWRs=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=EmOZ2tYUJCJhMhJ7hO34qV5fLR5s6c+Swyx0MdJ40FErxgl5j1pJ1C/4mPxfC/fB0 zDT+DR54Mvr4RmVYj3PS0INYq5at6DJwiJvlBLToBENbgbSF9qThUiahmn/iImdMun PbRfcsONPOAz/DgAjZkxiEiueS6TUZ5Yi6L6FvhGBVc1jkT4KNRf3lkY+HfN1hSh2D VFR2AVLEomJrR2LGmXga00ZjV0tf0hkN6eRbDVRD4D3G41ruz+/5U7xBTi7fc6s7L4 8rXROIj6mbaHHv12TMfkAL0zqssrdoHVk7BA+B8lqyVX07XUu8TZWdW8z9DNOBAnTQ 2mlgvyFVXCLDQ== From: Mark Brown Date: Mon, 07 Aug 2023 23:00:14 +0100 Subject: [PATCH v4 09/36] arm64/mm: Allocate PIE slots for EL0 guarded control stack MIME-Version: 1.0 Message-Id: <20230807-arm64-gcs-v4-9-68cfa37f9069@kernel.org> References: <20230807-arm64-gcs-v4-0-68cfa37f9069@kernel.org> In-Reply-To: <20230807-arm64-gcs-v4-0-68cfa37f9069@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-034f2 X-Developer-Signature: v=1; a=openpgp-sha256; l=2919; i=broonie@kernel.org; h=from:subject:message-id; bh=BgZhQzy1ZDJ87SbUj0QMsK2M0tcAHYl7N7+4HCzYWRs=; b=owEBbQGS/pANAwAKASTWi3JdVIfQAcsmYgBk0WmfSCjgX4zgvM1dX0NE3FBZc7yto4Ja/r7dY9ZP YJvd+7mJATMEAAEKAB0WIQSt5miqZ1cYtZ/in+ok1otyXVSH0AUCZNFpnwAKCRAk1otyXVSH0LkeB/ 487t0CeDsRzEJ/l8PbvmVhXGzZVKGNciRrG6v29QenKmFmWK3ROkp6BzL/Dr4xPkYV9tDVG69jz2aW noHAWdge6E/0geaaJAFe05seIm9jrY46BFHIZxolVLKZH4oFO0uG3qyA+Ct9k2m2RQI+zLhSAIj2Ue aO41sp2HhKo8umHeqzwsPEdHCZIlmQUPrK3X5emQgDFo/6iYIl7t2GRErkfDQdNq6kI+7i78vRgwHs M1fyR9/182RGa2FTE6YB6iQZY9Jpp1ngitVNFnpgQz7Gn9UTy5WHOU9xWttf7pOQFH7FZ3OIQ7BGRe w9VbzxIICBHqJFtASettRlZBpIAvmI X-Developer-Key: i=broonie@kernel.org; a=openpgp; fpr=3F2568AAC26998F9E813A1C5C3F436CA30F5D8EB Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org Pages used for guarded control stacks need to be described to the hardware using the Permission Indirection Extension, GCS is not supported without PIE. In order to support copy on write for guarded stacks we allocate two values, one for active GCSs and one for GCS pages marked as read only prior to copy. Since the actual effect is defined using PIE the specific bit pattern used does not matter to the hardware but we choose two values which differ only in PTE_WRITE in order to help share code with non-PIE cases. Signed-off-by: Mark Brown --- arch/arm64/include/asm/pgtable-prot.h | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-) diff --git a/arch/arm64/include/asm/pgtable-prot.h b/arch/arm64/include/asm/pgtable-prot.h index eed814b00a38..b157ae0420ed 100644 --- a/arch/arm64/include/asm/pgtable-prot.h +++ b/arch/arm64/include/asm/pgtable-prot.h @@ -131,15 +131,23 @@ extern bool arm64_use_ng_mappings; /* 6: PTE_PXN | PTE_WRITE */ /* 7: PAGE_SHARED_EXEC PTE_PXN | PTE_WRITE | PTE_USER */ /* 8: PAGE_KERNEL_ROX PTE_UXN */ -/* 9: PTE_UXN | PTE_USER */ +/* 9: PAGE_GCS_RO PTE_UXN | PTE_USER */ /* a: PAGE_KERNEL_EXEC PTE_UXN | PTE_WRITE */ -/* b: PTE_UXN | PTE_WRITE | PTE_USER */ +/* b: PAGE_GCS PTE_UXN | PTE_WRITE | PTE_USER */ /* c: PAGE_KERNEL_RO PTE_UXN | PTE_PXN */ /* d: PAGE_READONLY PTE_UXN | PTE_PXN | PTE_USER */ /* e: PAGE_KERNEL PTE_UXN | PTE_PXN | PTE_WRITE */ /* f: PAGE_SHARED PTE_UXN | PTE_PXN | PTE_WRITE | PTE_USER */ +#define _PAGE_GCS (_PAGE_DEFAULT | PTE_UXN | PTE_WRITE | PTE_USER) +#define _PAGE_GCS_RO (_PAGE_DEFAULT | PTE_UXN | PTE_USER) + +#define PAGE_GCS __pgprot(_PAGE_GCS) +#define PAGE_GCS_RO __pgprot(_PAGE_GCS_RO) + #define PIE_E0 ( \ + PIRx_ELx_PERM(pte_pi_index(_PAGE_GCS), PIE_GCS) | \ + PIRx_ELx_PERM(pte_pi_index(_PAGE_GCS_RO), PIE_R) | \ PIRx_ELx_PERM(pte_pi_index(_PAGE_EXECONLY), PIE_X_O) | \ PIRx_ELx_PERM(pte_pi_index(_PAGE_READONLY_EXEC), PIE_RX) | \ PIRx_ELx_PERM(pte_pi_index(_PAGE_SHARED_EXEC), PIE_RWX) | \ @@ -147,6 +155,8 @@ extern bool arm64_use_ng_mappings; PIRx_ELx_PERM(pte_pi_index(_PAGE_SHARED), PIE_RW)) #define PIE_E1 ( \ + PIRx_ELx_PERM(pte_pi_index(_PAGE_GCS), PIE_RW) | \ + PIRx_ELx_PERM(pte_pi_index(_PAGE_GCS_RO), PIE_R) | \ PIRx_ELx_PERM(pte_pi_index(_PAGE_EXECONLY), PIE_NONE_O) | \ PIRx_ELx_PERM(pte_pi_index(_PAGE_READONLY_EXEC), PIE_R) | \ PIRx_ELx_PERM(pte_pi_index(_PAGE_SHARED_EXEC), PIE_RW) | \