From patchwork Wed Oct 20 17:35:54 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kees Cook X-Patchwork-Id: 12572825 X-Patchwork-Delegate: keescook@chromium.org 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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2BBEBC4167D for ; Wed, 20 Oct 2021 17:36:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 12C9B610EA for ; Wed, 20 Oct 2021 17:36:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230329AbhJTRiP (ORCPT ); Wed, 20 Oct 2021 13:38:15 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38442 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230420AbhJTRiL (ORCPT ); Wed, 20 Oct 2021 13:38:11 -0400 Received: from mail-pj1-x1035.google.com (mail-pj1-x1035.google.com [IPv6:2607:f8b0:4864:20::1035]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3FA3DC06176E for ; Wed, 20 Oct 2021 10:35:57 -0700 (PDT) Received: by mail-pj1-x1035.google.com with SMTP id oa12-20020a17090b1bcc00b0019f715462a8so2952611pjb.3 for ; Wed, 20 Oct 2021 10:35:57 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=y1XRomZ8Io7favCHYT3bnx2s+fAILcX1u70AHtBS8Pw=; b=LVALPJH/SaUOIt6tZIPCSWPo1H2JwFkEu1rbLRKHJSKLX0Fe2p+vDLyPsA6xKrmpay 2/adVT1XNUTiHSjePbzWz4fFYJhY1SGWKAYGsFl0WnNq5UxfMmVfRcZztjIwIYEIxt3i Od9hD3+Z9ELsNgag3q6EmXfQZ6WAXDCJxbgHo= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=y1XRomZ8Io7favCHYT3bnx2s+fAILcX1u70AHtBS8Pw=; b=hoog7oshRFm9KaOL58W3QvGCW9pmaz+qBTzVHhptJH7vUNz/BZ4l9GIy2h0AIbeNd4 Pf7XdAs3Xe2fw8eqtKOp2uZ4ITjygrHuFpKgqOyxpXP5hGQlsLUThMEUV99PSAYr6DnO dcqSm4Lu0dL1PVWi0PNER5S9xVUQ4uBaobG4SzHxUcFLZ5osdyCxMQR69NKdv7QaNNPX bRvYIPoWEZq0vzU8abqMmV8OcoAJH6Sad3+GC1O1jOXPgjJK5PzTBR8ZOSK9oTYgEZ23 dOXzXhT76Y+y08w3adqzsdrn7qxSqQiI28LOSyLrnxOlWCe4G6vmx4P/J6PmsGz94kPS H6wg== X-Gm-Message-State: AOAM532exUFhMAQpFTJWjA5zDdnNufSBuXiSs8soGzdG9chX0onCxdo9 flUytmfgJE50VVz26pMwzprRgA== X-Google-Smtp-Source: ABdhPJz1Usn7FsIMGM086r+0uc2HiWD32fZOkmfv4SUsDanHb7JXEZzWHcQqdvPT3HCTBiJIoKzUjQ== X-Received: by 2002:a17:90a:718b:: with SMTP id i11mr468924pjk.22.1634751356652; Wed, 20 Oct 2021 10:35:56 -0700 (PDT) Received: from www.outflux.net (smtp.outflux.net. [198.145.64.163]) by smtp.gmail.com with ESMTPSA id v22sm3266439pff.93.2021.10.20.10.35.56 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 20 Oct 2021 10:35:56 -0700 (PDT) From: Kees Cook To: Kees Cook Cc: Masahiro Yamada , Michal Marek , Nick Desaulniers , Jonathan Corbet , linux-hardening@vger.kernel.org, linux-kbuild@vger.kernel.org, linux-doc@vger.kernel.org, Dan Li , ardb@kernel.org, ojeda@kernel.org, James Morris , "Serge E. Hallyn" , Nathan Chancellor , linux-kernel@vger.kernel.org, linux-security-module@vger.kernel.org, llvm@lists.linux.dev Subject: [PATCH 2/2] gcc-plugins: Remove cyc_complexity Date: Wed, 20 Oct 2021 10:35:54 -0700 Message-Id: <20211020173554.38122-3-keescook@chromium.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20211020173554.38122-1-keescook@chromium.org> References: <20211020173554.38122-1-keescook@chromium.org> MIME-Version: 1.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=5284; h=from:subject; bh=f2Np39be8zJVYWgx0MLtNjd71k0ksUQOTt8kvkajL04=; b=owEBbQKS/ZANAwAKAYly9N/cbcAmAcsmYgBhcFN51/MMK5PHASvRnsuVs7LQ9NKVVm1rmcssDUDA wONxnBWJAjMEAAEKAB0WIQSlw/aPIp3WD3I+bhOJcvTf3G3AJgUCYXBTeQAKCRCJcvTf3G3AJnCBD/ 9jWTO6a8sOqL7zQXVu/EiXql18cf8YSXnFWBxaTujzSjaSRjF9ivILZRxR1yk1g9eKEsFYJ+ziJvJV Q4jpD8gqM2wtH/wWEQyfRl38sYUJeOpyWNLWvKWJcMM8dNAiTGCfujbDMCAPQAARORXUqlJlI/8iOE ppZ21R7oHGDeFHGzKLc/OUnxo6OuWLb855Z9hBCEXWZAJ1G9NeujwYLCtaHMXmCyG1Xgd8x/CU+HiD mkAsaWbDfZeKKXYlcLlRmd4TV380UAz5lANqoXdcMnbFqMSkG82JuwBs+/z70afm2OqNjtEWcBbmc+ heX1tUsKYWekMN4h7EQGyuE4YtYta0TVjLKYwSR3LiX4yZdsKUS94RiZMM56HHymWkQQjdbCgTj7BM PInUl+JAVFqYlaBj3Rr5UkHeN0tPoVIIHq6TDIZkie+RRF1HQqJKaptOcOh07dI/6Z4cC2V/qhedmt O0Xh3lpGLCwuWbL/JiyAng13B/Nw5B48knBt/wzUOOwykfHJannZz9/6NiBrXzhWsARHoHjdbt9yK0 LAcWZSRnIhCObuCCRXD3GcMxey8UWQaTOisPhI1bNXt5h3+N020zRywYJ+y6f7eyErAY5LZg+r/HBy 2AzAqmv5Iw3L8ovjrVBSj/Gsh7aD7Obk0o5MOp4o7LloSugDViYk6OPa5vRQ== X-Developer-Key: i=keescook@chromium.org; a=openpgp; fpr=A5C3F68F229DD60F723E6E138972F4DFDC6DC026 Precedence: bulk List-ID: X-Mailing-List: linux-hardening@vger.kernel.org This plugin has no impact on the resulting binary, is disabled under COMPILE_TEST, and is not enabled on any builds I'm aware of. Additionally, given the clarified purpose of GCC plugins in the kernel, remove cyc_complexity. Cc: Masahiro Yamada Cc: Michal Marek Cc: Nick Desaulniers Cc: Jonathan Corbet Cc: linux-hardening@vger.kernel.org Cc: linux-kbuild@vger.kernel.org Cc: linux-doc@vger.kernel.org Signed-off-by: Kees Cook Reviewed-by: Miguel Ojeda Reviewed-by: Nathan Chancellor --- Documentation/kbuild/gcc-plugins.rst | 2 - scripts/Makefile.gcc-plugins | 2 - scripts/gcc-plugins/Kconfig | 16 ----- scripts/gcc-plugins/cyc_complexity_plugin.c | 69 --------------------- 4 files changed, 89 deletions(-) delete mode 100644 scripts/gcc-plugins/cyc_complexity_plugin.c diff --git a/Documentation/kbuild/gcc-plugins.rst b/Documentation/kbuild/gcc-plugins.rst index 4b28c7a4032f..0ba76719f1b9 100644 --- a/Documentation/kbuild/gcc-plugins.rst +++ b/Documentation/kbuild/gcc-plugins.rst @@ -96,7 +96,6 @@ Enable the GCC plugin infrastructure and some plugin(s) you want to use in the kernel config:: CONFIG_GCC_PLUGINS=y - CONFIG_GCC_PLUGIN_CYC_COMPLEXITY=y CONFIG_GCC_PLUGIN_LATENT_ENTROPY=y ... @@ -115,4 +114,3 @@ The GCC plugins are in scripts/gcc-plugins/. You need to put plugin source files right under scripts/gcc-plugins/. Creating subdirectories is not supported. It must be added to scripts/gcc-plugins/Makefile, scripts/Makefile.gcc-plugins and a relevant Kconfig file. -See the cyc_complexity_plugin.c (CONFIG_GCC_PLUGIN_CYC_COMPLEXITY) GCC plugin. diff --git a/scripts/Makefile.gcc-plugins b/scripts/Makefile.gcc-plugins index 952e46876329..6583ecf2e674 100644 --- a/scripts/Makefile.gcc-plugins +++ b/scripts/Makefile.gcc-plugins @@ -1,7 +1,5 @@ # SPDX-License-Identifier: GPL-2.0 -gcc-plugin-$(CONFIG_GCC_PLUGIN_CYC_COMPLEXITY) += cyc_complexity_plugin.so - gcc-plugin-$(CONFIG_GCC_PLUGIN_LATENT_ENTROPY) += latent_entropy_plugin.so gcc-plugin-cflags-$(CONFIG_GCC_PLUGIN_LATENT_ENTROPY) \ += -DLATENT_ENTROPY_PLUGIN diff --git a/scripts/gcc-plugins/Kconfig b/scripts/gcc-plugins/Kconfig index 3f5d3580ec06..821a725a7f5c 100644 --- a/scripts/gcc-plugins/Kconfig +++ b/scripts/gcc-plugins/Kconfig @@ -19,22 +19,6 @@ menuconfig GCC_PLUGINS if GCC_PLUGINS -config GCC_PLUGIN_CYC_COMPLEXITY - bool "Compute the cyclomatic complexity of a function" if EXPERT - depends on !COMPILE_TEST # too noisy - help - The complexity M of a function's control flow graph is defined as: - M = E - N + 2P - where - - E = the number of edges - N = the number of nodes - P = the number of connected components (exit nodes). - - Enabling this plugin reports the complexity to stderr during the - build. It mainly serves as a simple example of how to create a - gcc plugin for the kernel. - config GCC_PLUGIN_SANCOV bool # Plugin can be removed once the kernel only supports GCC 6.1.0+ diff --git a/scripts/gcc-plugins/cyc_complexity_plugin.c b/scripts/gcc-plugins/cyc_complexity_plugin.c deleted file mode 100644 index 73124c2b3edd..000000000000 --- a/scripts/gcc-plugins/cyc_complexity_plugin.c +++ /dev/null @@ -1,69 +0,0 @@ -/* - * Copyright 2011-2016 by Emese Revfy - * Licensed under the GPL v2, or (at your option) v3 - * - * Homepage: - * https://github.com/ephox-gcc-plugins/cyclomatic_complexity - * - * https://en.wikipedia.org/wiki/Cyclomatic_complexity - * The complexity M is then defined as: - * M = E - N + 2P - * where - * - * E = the number of edges of the graph - * N = the number of nodes of the graph - * P = the number of connected components (exit nodes). - * - * Usage (4.5 - 5): - * $ make clean; make run - */ - -#include "gcc-common.h" - -__visible int plugin_is_GPL_compatible; - -static struct plugin_info cyc_complexity_plugin_info = { - .version = "20160225", - .help = "Cyclomatic Complexity\n", -}; - -static unsigned int cyc_complexity_execute(void) -{ - int complexity; - expanded_location xloc; - - /* M = E - N + 2P */ - complexity = n_edges_for_fn(cfun) - n_basic_blocks_for_fn(cfun) + 2; - - xloc = expand_location(DECL_SOURCE_LOCATION(current_function_decl)); - fprintf(stderr, "Cyclomatic Complexity %d %s:%s\n", complexity, - xloc.file, DECL_NAME_POINTER(current_function_decl)); - - return 0; -} - -#define PASS_NAME cyc_complexity - -#define NO_GATE -#define TODO_FLAGS_FINISH TODO_dump_func - -#include "gcc-generate-gimple-pass.h" - -__visible int plugin_init(struct plugin_name_args *plugin_info, struct plugin_gcc_version *version) -{ - const char * const plugin_name = plugin_info->base_name; - - PASS_INFO(cyc_complexity, "ssa", 1, PASS_POS_INSERT_AFTER); - - if (!plugin_default_version_check(version, &gcc_version)) { - error(G_("incompatible gcc/plugin versions")); - return 1; - } - - register_callback(plugin_name, PLUGIN_INFO, NULL, - &cyc_complexity_plugin_info); - register_callback(plugin_name, PLUGIN_PASS_MANAGER_SETUP, NULL, - &cyc_complexity_pass_info); - - return 0; -}