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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 83D14C52D7C for ; Fri, 23 Aug 2024 09:50:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=ibPOTwgg/Z4pmQA9vlGECC5um2krnKdHAhwkgDhcNU8=; b=jGw5nKdsUeFSBGQGpoV8EU9Phi Ve/ObEUZh0goyUd5PgB3qVW/ZmwWw2UPkWtGkJx2buuozsUEAzSWdWXGFkUjRI9q165lA+iwMV+BS M+4faTOKSjNkEo0fWybjHwmuQ/DPDDT/zN0ZSHU2y1ccfvhmxuQJofgtu8EwOVyegYF1Ws7lZ4WAH bb7SwYje8M8Bu2cFJYQuLskJshhJcBSmqcCoGYC8ctL5kKthR2pTjceV2PCiT+hzuSEQt27OBlneS H2RUGMXGa/P5xPLgILpWlsER+mc1B9zarHU1jRoKFGugmiEpkICLaQhQ5K9z85z1IhUst/E6ytYCp nrkVo7qg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1shQw7-0000000GCG1-3dxD; Fri, 23 Aug 2024 09:50:27 +0000 Received: from nyc.source.kernel.org ([147.75.193.91]) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1shQuf-0000000GBqr-1BYf; Fri, 23 Aug 2024 09:48:58 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by nyc.source.kernel.org (Postfix) with ESMTP id 74FB1A42641; Fri, 23 Aug 2024 09:48:49 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id B6993C32786; Fri, 23 Aug 2024 09:48:49 +0000 (UTC) Date: Fri, 23 Aug 2024 10:48:47 +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 , Yury Khrustalev , Wilco Dijkstra , 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 v11 27/39] arm64: Add Kconfig for Guarded Control Stack (GCS) Message-ID: References: <20240822-arm64-gcs-v11-0-41b81947ecb5@kernel.org> <20240822-arm64-gcs-v11-27-41b81947ecb5@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20240822-arm64-gcs-v11-27-41b81947ecb5@kernel.org> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240823_024857_408920_0ABC697B X-CRM114-Status: GOOD ( 18.54 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Thu, Aug 22, 2024 at 02:15:30AM +0100, Mark Brown wrote: > diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig > index a2f8ff354ca6..772f9ba99fe8 100644 > --- a/arch/arm64/Kconfig > +++ b/arch/arm64/Kconfig > @@ -2137,6 +2137,26 @@ 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_HAS_USER_SHADOW_STACK > + 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 # "v9.4 architectural features" BTW, as Mark R spotted we'd also need to handle uprobes. Since that's off in defconfig, I think it can be done separately on top of this series. In the meantime, we could make this dependent on !UPROBES. -- Catalin