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 X-Spam-Level: X-Spam-Status: No, score=-8.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 20283C3F68F for ; Thu, 16 Jan 2020 17:40:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id DBD3924696 for ; Thu, 16 Jan 2020 17:40:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579196452; bh=euJA6zdxXJ1OpER7tf/R3kpDg450PVX85nEcb4d8ZzQ=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=XUDJi3PbgWWp9EaBjSt6ZLUZ/t2OtoBTKM3GiaPnvaXt3t0Sj2S4YbeNoqkC41OGO meG/bfs4TwVlZ83AIJfHHaIHmakmzib5HyymZfnl9GB0JjNQol5XUVit9wpkxZtXkp lekzqTELAJHxgLm4JbdkRhW4XRKQ0EVV2xuR10fo= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2405125AbgAPRkv (ORCPT ); Thu, 16 Jan 2020 12:40:51 -0500 Received: from mail.kernel.org ([198.145.29.99]:56694 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2393425AbgAPRj5 (ORCPT ); Thu, 16 Jan 2020 12:39:57 -0500 Received: from willie-the-truck (236.31.169.217.in-addr.arpa [217.169.31.236]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 3458E24706; Thu, 16 Jan 2020 17:39:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579196397; bh=euJA6zdxXJ1OpER7tf/R3kpDg450PVX85nEcb4d8ZzQ=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=PjGV/BPsPkpco5bu27nYxZQvO9xiW4VIFDMeF0zaF5C0Ti5cMJbhN/BTuggIf3g7w EEeKCYCLG7UMT6aIKCgfFWTnFzTEO8Y+4Khh0O0kVq3zDlFsMTEKLuH1/6fKcakRWh 7bY4ukqYCxg396Yb9t9aBgkzy6GJ2+SaCj5w+8KE= Date: Thu, 16 Jan 2020 17:39:51 +0000 From: Will Deacon To: Sami Tolvanen Cc: Catalin Marinas , Steven Rostedt , Masami Hiramatsu , Ard Biesheuvel , Mark Rutland , Dave Martin , Kees Cook , Laura Abbott , Marc Zyngier , Nick Desaulniers , Jann Horn , Miguel Ojeda , Masahiro Yamada , clang-built-linux@googlegroups.com, kernel-hardening@lists.openwall.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v6 08/15] arm64: disable function graph tracing with SCS Message-ID: <20200116173950.GB21396@willie-the-truck> References: <20191018161033.261971-1-samitolvanen@google.com> <20191206221351.38241-1-samitolvanen@google.com> <20191206221351.38241-9-samitolvanen@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20191206221351.38241-9-samitolvanen@google.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Dec 06, 2019 at 02:13:44PM -0800, Sami Tolvanen wrote: > The graph tracer hooks returns by modifying frame records on the > (regular) stack, but with SCS the return address is taken from the > shadow stack, and the value in the frame record has no effect. As we > don't currently have a mechanism to determine the corresponding slot > on the shadow stack (and to pass this through the ftrace > infrastructure), for now let's disable the graph tracer when SCS is > enabled. > > Signed-off-by: Sami Tolvanen > Reviewed-by: Kees Cook > Reviewed-by: Mark Rutland > --- > arch/arm64/Kconfig | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig > index b1b4476ddb83..49e5f94ff4af 100644 > --- a/arch/arm64/Kconfig > +++ b/arch/arm64/Kconfig > @@ -149,7 +149,7 @@ config ARM64 > select HAVE_FTRACE_MCOUNT_RECORD > select HAVE_FUNCTION_TRACER > select HAVE_FUNCTION_ERROR_INJECTION > - select HAVE_FUNCTION_GRAPH_TRACER > + select HAVE_FUNCTION_GRAPH_TRACER if !SHADOW_CALL_STACK > select HAVE_GCC_PLUGINS > select HAVE_HW_BREAKPOINT if PERF_EVENTS > select HAVE_IRQ_TIME_ACCOUNTING I think this is the wrong way around, as we support the graph tracer today and so I think SHADOW_CALL_STACK should depend on !GRAPH_TRACER and possibly even EXPERT until this is resolved. Will 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 X-Spam-Level: X-Spam-Status: No, score=-8.5 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 23DB9C33CB6 for ; Thu, 16 Jan 2020 18:23:26 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id ED2772051A for ; Thu, 16 Jan 2020 18:23:25 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="uFSZmP5p"; dkim=fail reason="signature verification failed" (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="PjGV/BPs" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org ED2772051A Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=C5vYxwsyM3NBdqNpThTluwOLWnSg6J3WHNaBDhZ/Daw=; b=uFSZmP5pnxB1O2 cW65J1e4op/64kSHwc95amYSaYXD24aS9Bwvji7Lv2VZKlZ0KX5yp1wmpRodhLw+xax3zJiInMi9n 14dPqMv3D97QeHTYLOl0ZzVj5uvhQrQXZQjyejI3wlXVf7sQrG5gYnCf/VTkywFGkhWrqqg5aR/6N geW1krAB2zpLLGHiFqQ++HZTz5MAX5DWrOYe/BIpJARSJ4cg4N5wLrfREW8/OkpqQ2tXXhu53d1O2 34rc264tjiaFaQJ8TAaGm8UBzr0PkFR8AEy4Kzh4W42f+hhhTYGnG1huArLWlsKDDQR41HyQY9Cm2 L7wCAQ0N4Q7moXkdZk2w==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1is9ng-0008Rl-P9; Thu, 16 Jan 2020 18:23:24 +0000 Received: from mail.kernel.org ([198.145.29.99]) by bombadil.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1is97d-0008DB-E1 for linux-arm-kernel@lists.infradead.org; Thu, 16 Jan 2020 17:40:05 +0000 Received: from willie-the-truck (236.31.169.217.in-addr.arpa [217.169.31.236]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 3458E24706; Thu, 16 Jan 2020 17:39:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579196397; bh=euJA6zdxXJ1OpER7tf/R3kpDg450PVX85nEcb4d8ZzQ=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=PjGV/BPsPkpco5bu27nYxZQvO9xiW4VIFDMeF0zaF5C0Ti5cMJbhN/BTuggIf3g7w EEeKCYCLG7UMT6aIKCgfFWTnFzTEO8Y+4Khh0O0kVq3zDlFsMTEKLuH1/6fKcakRWh 7bY4ukqYCxg396Yb9t9aBgkzy6GJ2+SaCj5w+8KE= Date: Thu, 16 Jan 2020 17:39:51 +0000 From: Will Deacon To: Sami Tolvanen Subject: Re: [PATCH v6 08/15] arm64: disable function graph tracing with SCS Message-ID: <20200116173950.GB21396@willie-the-truck> References: <20191018161033.261971-1-samitolvanen@google.com> <20191206221351.38241-1-samitolvanen@google.com> <20191206221351.38241-9-samitolvanen@google.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20191206221351.38241-9-samitolvanen@google.com> User-Agent: Mutt/1.10.1 (2018-07-13) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200116_093957_532206_E198E4A0 X-CRM114-Status: GOOD ( 18.07 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Mark Rutland , Kees Cook , Ard Biesheuvel , Masahiro Yamada , Catalin Marinas , Jann Horn , Nick Desaulniers , linux-kernel@vger.kernel.org, Steven Rostedt , Miguel Ojeda , clang-built-linux@googlegroups.com, Masami Hiramatsu , Marc Zyngier , kernel-hardening@lists.openwall.com, Laura Abbott , Dave Martin , linux-arm-kernel@lists.infradead.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Fri, Dec 06, 2019 at 02:13:44PM -0800, Sami Tolvanen wrote: > The graph tracer hooks returns by modifying frame records on the > (regular) stack, but with SCS the return address is taken from the > shadow stack, and the value in the frame record has no effect. As we > don't currently have a mechanism to determine the corresponding slot > on the shadow stack (and to pass this through the ftrace > infrastructure), for now let's disable the graph tracer when SCS is > enabled. > > Signed-off-by: Sami Tolvanen > Reviewed-by: Kees Cook > Reviewed-by: Mark Rutland > --- > arch/arm64/Kconfig | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig > index b1b4476ddb83..49e5f94ff4af 100644 > --- a/arch/arm64/Kconfig > +++ b/arch/arm64/Kconfig > @@ -149,7 +149,7 @@ config ARM64 > select HAVE_FTRACE_MCOUNT_RECORD > select HAVE_FUNCTION_TRACER > select HAVE_FUNCTION_ERROR_INJECTION > - select HAVE_FUNCTION_GRAPH_TRACER > + select HAVE_FUNCTION_GRAPH_TRACER if !SHADOW_CALL_STACK > select HAVE_GCC_PLUGINS > select HAVE_HW_BREAKPOINT if PERF_EVENTS > select HAVE_IRQ_TIME_ACCOUNTING I think this is the wrong way around, as we support the graph tracer today and so I think SHADOW_CALL_STACK should depend on !GRAPH_TRACER and possibly even EXPERT until this is resolved. Will _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel