From patchwork Mon Jul 24 12:45:57 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mark Brown X-Patchwork-Id: 13324609 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 1CD25C001DE for ; Mon, 24 Jul 2023 12:49:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231299AbjGXMtm (ORCPT ); Mon, 24 Jul 2023 08:49:42 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38924 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230023AbjGXMtN (ORCPT ); Mon, 24 Jul 2023 08:49:13 -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 3FA72E77; Mon, 24 Jul 2023 05:48:05 -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 BA0FE61166; Mon, 24 Jul 2023 12:48:02 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5AE72C433C8; Mon, 24 Jul 2023 12:47:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1690202882; bh=XgAXaxiI+LNUcKtRlH2zykI6sDdksLTFFqJ3d2DlV6Q=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=QGcM4fnx8swpQgYlAoCdgwpYJMLiVk400mojxwsQVLI9u7WmzRJGtjcGmpf1rONDi Xtl0CNWv/G1fjwhLgbOmsjdZGuyrmwVKXp/5dm+/vQL9JmjprgmAxj1w9oVlZOaTTX ofd0nIM5qeZ3BWWsFtmVr8FT6ONga/FRlNL+mdbnCRYlQGpV05t1flnZD1i4BKnzO+ nuShnz44zVYhXhF38ilgLT0jabJMYVYktsFVB4G3zxi1wzrt5470MePGh4sNQ8PIs1 ck/eqVSuihlN6lGd64GLZFrREDPRbgtoDzTm5R3dJtKyDCT2EkNa1yntyc8ts7GnJs +XXpha8iGolAg== From: Mark Brown Date: Mon, 24 Jul 2023 13:45:57 +0100 Subject: [PATCH v2 10/35] mm: Define VM_SHADOW_STACK for arm64 when we support GCS MIME-Version: 1.0 Message-Id: <20230724-arm64-gcs-v2-10-dc2c1d44c2eb@kernel.org> References: <20230724-arm64-gcs-v2-0-dc2c1d44c2eb@kernel.org> In-Reply-To: <20230724-arm64-gcs-v2-0-dc2c1d44c2eb@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=2027; i=broonie@kernel.org; h=from:subject:message-id; bh=XgAXaxiI+LNUcKtRlH2zykI6sDdksLTFFqJ3d2DlV6Q=; b=owEBbQGS/pANAwAKASTWi3JdVIfQAcsmYgBkvnKOdTEcLahkBp5IvWyRhmcZw9T/1AqgLdEteVGJ Q6Hg5S2JATMEAAEKAB0WIQSt5miqZ1cYtZ/in+ok1otyXVSH0AUCZL5yjgAKCRAk1otyXVSH0J4CB/ 9rhqw0udDoYi8sudj/nInZ2l8ch9RyA2y9LlyMnS5EK2PCPsTlwwDG8zCkzr2Jf//EF5g3JIkU3F+J XthObw2KIyQ0tYX6oE97ECWKXNidZz8FppyIjF+x/kMI9CeBzOqWvEPh8t2unhLhgWVMqR8NmNMypi pnXvc7tLLYYFLfJFYfdsQvaEhlRbAwtAxBJi3WlKEUh8fGTnLU004p6Csd8bW3V2rkU3ApTPpkp51M asuqbjt59yH0eTxwGOfrL1qj8Lui/gvJDdjlwnzphEwC/rwfKQhcy8Chgg/9rRm/hQrcawBHad4rWx dfQezidZRepEyWt91teiL0228x6T8k X-Developer-Key: i=broonie@kernel.org; a=openpgp; fpr=3F2568AAC26998F9E813A1C5C3F436CA30F5D8EB Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org Use VM_HIGH_ARCH_5 for guarded control stack pages. Signed-off-by: Mark Brown --- Documentation/filesystems/proc.rst | 2 +- fs/proc/task_mmu.c | 3 +++ include/linux/mm.h | 12 +++++++++++- 3 files changed, 15 insertions(+), 2 deletions(-) diff --git a/Documentation/filesystems/proc.rst b/Documentation/filesystems/proc.rst index 6ccb57089a06..086a0408a4d7 100644 --- a/Documentation/filesystems/proc.rst +++ b/Documentation/filesystems/proc.rst @@ -566,7 +566,7 @@ encoded manner. The codes are the following: mt arm64 MTE allocation tags are enabled um userfaultfd missing tracking uw userfaultfd wr-protect tracking - ss shadow stack page + ss shadow/guarded control stack page == ======================================= Note that there is no guarantee that every flag and associated mnemonic will diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c index cfab855fe7e9..e8c50848bb16 100644 --- a/fs/proc/task_mmu.c +++ b/fs/proc/task_mmu.c @@ -711,6 +711,9 @@ static void show_smap_vma_flags(struct seq_file *m, struct vm_area_struct *vma) #endif /* CONFIG_HAVE_ARCH_USERFAULTFD_MINOR */ #ifdef CONFIG_X86_USER_SHADOW_STACK [ilog2(VM_SHADOW_STACK)] = "ss", +#endif +#ifdef CONFIG_ARM64_GCS + [ilog2(VM_SHADOW_STACK)] = "ss", #endif }; size_t i; diff --git a/include/linux/mm.h b/include/linux/mm.h index c57c5030ef6c..c6af8daceb56 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -372,7 +372,17 @@ extern unsigned int kobjsize(const void *objp); * having a PAGE_SIZE guard gap. */ # define VM_SHADOW_STACK VM_HIGH_ARCH_5 -#else +#endif + +#if defined(CONFIG_ARM64_GCS) +/* + * arm64's Guarded Control Stack implements similar functionality and + * has similar constraints to shadow stacks. + */ +# define VM_SHADOW_STACK VM_HIGH_ARCH_5 +#endif + +#ifndef VM_SHADOW_STACK # define VM_SHADOW_STACK VM_NONE #endif