From patchwork Wed Nov 22 09:42:21 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mark Brown X-Patchwork-Id: 13464370 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 B055D219FF; Wed, 22 Nov 2023 09:44:15 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="h210R7jL" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9F7A2C433CA; Wed, 22 Nov 2023 09:44:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1700646255; bh=gCkTJXN9hgWCfubwLDLAmQpOXrRFEWNkqe7LcsfqPUI=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=h210R7jLnqkzHFNW2i+bNC/uW8728czTflygATeqPHl26mTG4iNTO/3gkMXGYPXFf PH8vpoZOA7k8ZL9aFvlCjOOCziT6vy26FbZL1HE665xm4hvAUJvhE2zp6t9hzCfeqo t3IJNIHcA7tQBbVdWXAS2/RmKl+4V3XS5f8pVjvm5p17xaH9rKDG8KJPCnyHe4rKv0 HxFWNWYXflOIzbRkGZ3oNzHRXJweodM+ntU8HkYYfwHN9YnMhlU/AiZ+ctbxSLTi3K 3WwpCNuPtS29zMJyc0EWpf9s7RymWtpI9ltp4+horOAkwOTgBysp6m7F9DquRI7H+/ 0znHAiLzjXVdg== From: Mark Brown Date: Wed, 22 Nov 2023 09:42:21 +0000 Subject: [PATCH v7 11/39] arm64/mm: Allocate PIE slots for EL0 guarded control stack Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-Id: <20231122-arm64-gcs-v7-11-201c483bd775@kernel.org> References: <20231122-arm64-gcs-v7-0-201c483bd775@kernel.org> In-Reply-To: <20231122-arm64-gcs-v7-0-201c483bd775@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 , Florian Weimer , Christian Brauner , Thiago Jung Bauermann , 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-0438c X-Developer-Signature: v=1; a=openpgp-sha256; l=2936; i=broonie@kernel.org; h=from:subject:message-id; bh=gCkTJXN9hgWCfubwLDLAmQpOXrRFEWNkqe7LcsfqPUI=; b=owGbwMvMwMWocq27KDak/QLjabUkhtTYM/8lHrpkfRDKsNrcv+HM4ftX0yZd2fNToL57XXlv5 UOvmIi3nYzGLAyMXAyyYoosa59lrEoPl9g6/9H8VzCDWJlApjBwcQrARDYpsP937Bf6G8WaH8wS YTJz+hT7PkttgeLI1xVXNCfMl/p82eTBruI2duXO/qP+f9YFX1rxK9B2h3NLW5GFu63oJoVFOc7 nV3j7lmhOOmrZMmGVgMOGJ4cce5+8qrfkvBvQJLSi70Sdr71Os2Jxf7PPrIgIzU8e9Wx3HhrOE3 ysuznx3ozqD5f5a+2631l8OJr1ce1l7+Soja23YtudX1UYLvRvdFzOZWPi92LpBmcVmZ5psxr/6 r3u15w538Em9ti7wptlYtEt+X7dAtEnsv4v5Hn4b9vTpHNKzlr3+ULlnBjm/GI4y7naUo9PZJX0 9sqNSfN2StnU8k4oPOfcdSVw4iMT1+awP0b8OSEmRlssAQ== X-Developer-Key: i=broonie@kernel.org; a=openpgp; fpr=3F2568AAC26998F9E813A1C5C3F436CA30F5D8EB 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 e9624f6326dd..297a645e8a0f 100644 --- a/arch/arm64/include/asm/pgtable-prot.h +++ b/arch/arm64/include/asm/pgtable-prot.h @@ -127,15 +127,23 @@ 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_NG | PTE_UXN | PTE_WRITE | PTE_USER) +#define _PAGE_GCS_RO (_PAGE_DEFAULT | PTE_NG | 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) | \ @@ -143,6 +151,8 @@ 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_NONE_O) | \ + PIRx_ELx_PERM(pte_pi_index(_PAGE_GCS_RO), PIE_NONE_O) | \ 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) | \