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=-8.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_2 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 9D644CA9EA0 for ; Fri, 18 Oct 2019 17:01:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 67B4721D7C for ; Fri, 18 Oct 2019 17:01:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2501925AbfJRRBb (ORCPT ); Fri, 18 Oct 2019 13:01:31 -0400 Received: from mail.kernel.org ([198.145.29.99]:49830 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2387714AbfJRRBa (ORCPT ); Fri, 18 Oct 2019 13:01:30 -0400 Received: from gandalf.local.home (cpe-66-24-58-225.stny.res.rr.com [66.24.58.225]) (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 1DA092064A; Fri, 18 Oct 2019 17:01:29 +0000 (UTC) Date: Fri, 18 Oct 2019 13:01:27 -0400 From: Steven Rostedt To: Sami Tolvanen Cc: Will Deacon , Catalin Marinas , Ard Biesheuvel , Dave Martin , Kees Cook , Laura Abbott , Mark Rutland , Nick Desaulniers , clang-built-linux@googlegroups.com, kernel-hardening@lists.openwall.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 09/18] trace: disable function graph tracing with SCS Message-ID: <20191018130127.23746ff2@gandalf.local.home> In-Reply-To: <20191018161033.261971-10-samitolvanen@google.com> References: <20191018161033.261971-1-samitolvanen@google.com> <20191018161033.261971-10-samitolvanen@google.com> X-Mailer: Claws Mail 3.17.3 (GTK+ 2.24.32; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 18 Oct 2019 09:10:24 -0700 Sami Tolvanen wrote: > With CONFIG_FUNCTION_GRAPH_TRACER, function return addresses are > modified in ftrace_graph_caller and prepare_ftrace_return to redirect > control flow to ftrace_return_to_handler. This is incompatible with > return address protection. > > Signed-off-by: Sami Tolvanen > --- > kernel/trace/Kconfig | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig > index e08527f50d2a..b7e5e3bfa0f4 100644 > --- a/kernel/trace/Kconfig > +++ b/kernel/trace/Kconfig > @@ -161,6 +161,7 @@ config FUNCTION_GRAPH_TRACER > depends on HAVE_FUNCTION_GRAPH_TRACER > depends on FUNCTION_TRACER > depends on !X86_32 || !CC_OPTIMIZE_FOR_SIZE > + depends on ROP_PROTECTION_NONE NAK, Put this in the arch code. > default y > help > Enable the kernel to trace a function at both its return -- Steve diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 41a9b4257b72..d68339987604 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 ROP_PROTECTION_NONE select HAVE_GCC_PLUGINS select HAVE_HW_BREAKPOINT if PERF_EVENTS select HAVE_IRQ_TIME_ACCOUNTING