From mboxrd@z Thu Jan 1 00:00:00 1970 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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 746B2C52D7D for ; Thu, 15 Aug 2024 10:42:39 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id ED0C46B00C5; Thu, 15 Aug 2024 06:42:38 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id E80A16B00C6; Thu, 15 Aug 2024 06:42:38 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id D48926B00C7; Thu, 15 Aug 2024 06:42:38 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0013.hostedemail.com [216.40.44.13]) by kanga.kvack.org (Postfix) with ESMTP id B66066B00C5 for ; Thu, 15 Aug 2024 06:42:38 -0400 (EDT) Received: from smtpin02.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay06.hostedemail.com (Postfix) with ESMTP id 3FEBCA85D8 for ; Thu, 15 Aug 2024 10:42:38 +0000 (UTC) X-FDA: 82454141196.02.F03CAAB Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by imf19.hostedemail.com (Postfix) with ESMTP id A70F31A0007 for ; Thu, 15 Aug 2024 10:42:36 +0000 (UTC) Authentication-Results: imf19.hostedemail.com; dkim=none; spf=pass (imf19.hostedemail.com: domain of cmarinas@kernel.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=cmarinas@kernel.org; dmarc=fail reason="SPF not aligned (relaxed), No valid DKIM" header.from=arm.com (policy=none) ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1723718499; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=htvDFLr6IbGsuAmBAkByyu9KBbpd/W0aTtd1ouB5scE=; b=8NqyyW8B+tCoW/3KxMokkghYONujJcg9BL7tk0Cv2iNbZQG4aToZfFvqgsI56H07mObNtU B3xbcXyqteEZ4PMCBxA6Griwj4z/GcwRF5XwQ+8EQq1C4XM21awMdRr/smit2xWdDl2+ic /U7xX6pMrEe7Ua7Gfl6uDeJ2anacSEY= ARC-Authentication-Results: i=1; imf19.hostedemail.com; dkim=none; spf=pass (imf19.hostedemail.com: domain of cmarinas@kernel.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=cmarinas@kernel.org; dmarc=fail reason="SPF not aligned (relaxed), No valid DKIM" header.from=arm.com (policy=none) ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1723718499; a=rsa-sha256; cv=none; b=6VXoMWYBchGydNi78ImiVAcQ5GSc9PAQMajAaRQ0ji7J996WfLzzWnHaAbNHfovvli8aBe ZxjGYKX6yT5+GtIKDX39QBCCLOARbMzzcJj77c4848kXzG2mePMkePr4oaCG8rO/IV7gec IAZESkkObQ8UWiF8LvKIhqs07X1BxRc= Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by dfw.source.kernel.org (Postfix) with ESMTP id B843461DE5; Thu, 15 Aug 2024 10:42:35 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 36C1AC32786; Thu, 15 Aug 2024 10:42:30 +0000 (UTC) Date: Thu, 15 Aug 2024 11:42:28 +0100 From: Catalin Marinas To: Mark Brown Cc: Will Deacon , Jonathan Corbet , Andrew Morton , Marc Zyngier , Oliver Upton , James Morse , Suzuki K Poulose , Arnd Bergmann , Oleg Nesterov , Eric Biederman , Shuah Khan , "Rick P. Edgecombe" , Deepak Gupta , Ard Biesheuvel , Szabolcs Nagy , Kees Cook , "H.J. Lu" , Paul Walmsley , Palmer Dabbelt , Albert Ou , Florian Weimer , Christian Brauner , Thiago Jung Bauermann , Ross Burton , 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 Subject: Re: [PATCH v10 02/40] prctl: arch-agnostic prctl for shadow stack Message-ID: References: <20240801-arm64-gcs-v10-0-699e2bd2190b@kernel.org> <20240801-arm64-gcs-v10-2-699e2bd2190b@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20240801-arm64-gcs-v10-2-699e2bd2190b@kernel.org> X-Stat-Signature: hwainz56omrdbti6j9ezcs4ig8fkq41o X-Rspam-User: X-Rspamd-Queue-Id: A70F31A0007 X-Rspamd-Server: rspam02 X-HE-Tag: 1723718556-48013 X-HE-Meta: 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 HodsOi4M 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 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Thu, Aug 01, 2024 at 01:06:29PM +0100, Mark Brown wrote: > Three architectures (x86, aarch64, riscv) have announced support for > shadow stacks with fairly similar functionality. While x86 is using > arch_prctl() to control the functionality neither arm64 nor riscv uses > that interface so this patch adds arch-agnostic prctl() support to > get and set status of shadow stacks and lock the current configuation to > prevent further changes, with support for turning on and off individual > subfeatures so applications can limit their exposure to features that > they do not need. The features are: > > - PR_SHADOW_STACK_ENABLE: Tracking and enforcement of shadow stacks, > including allocation of a shadow stack if one is not already > allocated. > - PR_SHADOW_STACK_WRITE: Writes to specific addresses in the shadow > stack. > - PR_SHADOW_STACK_PUSH: Push additional values onto the shadow stack. > > These features are expected to be inherited by new threads and cleared > on exec(), unknown features should be rejected for enable but accepted > for locking (in order to allow for future proofing). > > This is based on a patch originally written by Deepak Gupta but modified > fairly heavily, support for indirect landing pads is removed, additional > modes added and the locking interface reworked. The set status prctl() > is also reworked to just set flags, if setting/reading the shadow stack > pointer is required this could be a separate prctl. > > Reviewed-by: Thiago Jung Bauermann > Signed-off-by: Mark Brown Reviewed-by: Catalin Marinas