From patchwork Tue Jul 14 23:23:49 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nathan Huckleberry X-Patchwork-Id: 11663943 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id D5EAE13B4 for ; Tue, 14 Jul 2020 23:24:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B7F272065E for ; Tue, 14 Jul 2020 23:24:18 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="dOfVLO3j" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726974AbgGNXYS (ORCPT ); Tue, 14 Jul 2020 19:24:18 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53198 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725977AbgGNXYR (ORCPT ); Tue, 14 Jul 2020 19:24:17 -0400 Received: from mail-il1-x14a.google.com (mail-il1-x14a.google.com [IPv6:2607:f8b0:4864:20::14a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8C181C061755 for ; Tue, 14 Jul 2020 16:24:17 -0700 (PDT) Received: by mail-il1-x14a.google.com with SMTP id d3so138786ilq.9 for ; Tue, 14 Jul 2020 16:24:17 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=2MgCYW3UINne2osnWjKqpbw5LUhaGCf3Xmk9thEs7q4=; b=dOfVLO3jlim0zb9WHzhTGm0jo6RhQKLeVileQs4onfYV8C0NDaTm8dCDLEcrtZYcKO zCez3YySkFunloZdbla++ue8szahSBXOepUxMJG+MNvW0BIaZAfzHFxtWnAegNuCE6er AZDMOzaUy/l9JdBX4MZIzbmSE20yp6rlakGW00sDCto2c9Rb5sOU67ZoH+WD/PGE8X0h E7aLCEB6UZd5AOeeUXcwMFhhqdc62OqNRDSEt7ASNsseVOe0l59s9qaoumTrZwxUqF7h 2D794wbhML3bHixXtG6cIMfrp6mCFxtM7j/a3PPJMnYp44Is97Q7yGGMveu5rkOGgRwD K7Aw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=2MgCYW3UINne2osnWjKqpbw5LUhaGCf3Xmk9thEs7q4=; b=uH0jKQRbbOzEG7dv7PVTEwjWMDiHVP7G5O4T/h8TPlsbyToPZtTAGdwFi+qsMK2GyW bzVp/hnzEuuPkM0ylL7fkXRsz9WjP+VtA5p9V6pKp1SJ9XRof5IQzoYbRke4OFyJ9a0G 6d0mokmrnHUyWu9OWZaN8woc51Wm4LuGIFKbvfeHkXsdGe4rpmJfqHTjVzG4qJUMFJrg i/eDnMrw1kVnbsiw+gTYDftJh4j19NYANe8xylt605pUIBzGa0/HQMRqgQv43cWACUxF /emRXmm3I7+6WbojReeDZrxUb1BmXrSSxJTBVW9CZGMKWMKZt+mPOTlU0GOfG8fXigiR ciUQ== X-Gm-Message-State: AOAM531zJ5XhhWBbIJnUeKtX35EO1+UsUCxwzi2cT/6SuvZG/nROeUbp pONIMJ6mtOWsrsGSNtCupB3skZ39Qw== X-Google-Smtp-Source: ABdhPJzA0rVDrfWNGsOJlpomXWRnd2FOUAwGD6tuO1OeT4r/rHHZbSfoauDyZdczZ04JNApzrb8tDzY1Xw== X-Received: by 2002:a05:6638:3aa:: with SMTP id z10mr8679368jap.54.1594769056604; Tue, 14 Jul 2020 16:24:16 -0700 (PDT) Date: Tue, 14 Jul 2020 23:23:49 +0000 In-Reply-To: <20200713225103.GA1095851@google.com> Message-Id: <20200714232349.2198114-1-nhuck@google.com> Mime-Version: 1.0 References: <20200713225103.GA1095851@google.com> X-Mailer: git-send-email 2.27.0.389.gc38d7665816-goog Subject: [PATCH v3] Makefile: Add clang-tidy and static analyzer support to makefile From: Nathan Huckleberry To: masahiroy@kernel.org, michal.lkml@markovi.net Cc: linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org, clang-built-linux@googlegroups.com, Nathan Huckleberry Sender: linux-kbuild-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org This patch adds clang-tidy and the clang static-analyzer as make targets. The goal of this patch is to make static analysis tools usable and extendable by any developer or researcher who is familiar with basic c++. The current static analysis tools require intimate knowledge of the internal workings of the static analysis. Clang-tidy and the clang static analyzers expose an easy to use api and allow users unfamiliar with clang to write new checks with relative ease. ===Clang-tidy=== Clang-tidy is an easily extendable 'linter' that runs on the AST. Clang-tidy checks are easy to write and understand. A check consists of two parts, a matcher and a checker. The matcher is created using a domain specific language that acts on the AST (https://clang.llvm.org/docs/LibASTMatchersReference.html). When AST nodes are found by the matcher a callback is made to the checker. The checker can then execute additional checks and issue warnings. Here is an example clang-tidy check to report functions that have calls to local_irq_disable without calls to local_irq_enable and vice-versa. Functions flagged with __attribute((annotation("ignore_irq_balancing"))) are ignored for analysis. (https://reviews.llvm.org/D65828) ===Clang static analyzer=== The clang static analyzer is a more powerful static analysis tool that uses symbolic execution to find bugs. Currently there is a check that looks for potential security bugs from invalid uses of kmalloc and kfree. There are several more general purpose checks that are useful for the kernel. The clang static analyzer is well documented and designed to be extensible. (https://clang-analyzer.llvm.org/checker_dev_manual.html) (https://github.com/haoNoQ/clang-analyzer-guide/releases/download/v0.1/clang-analyzer-guide-v0.1.pdf) The main draw of the clang tools is how accessible they are. The clang documentation is very nice and these tools are built specifically to be easily extendable by any developer. They provide an accessible method of bug-finding and research to people who are not overly familiar with the kernel codebase. Signed-off-by: Nathan Huckleberry --- Changes v2 -> v3 * Redirect clang-tidy output to stderr * Style fixes * Add directory to MAINTAINERS MAINTAINERS | 1 + Makefile | 3 + scripts/clang-tools/Makefile.clang-tools | 23 +++++++ .../{ => clang-tools}/gen_compile_commands.py | 0 scripts/clang-tools/run-clang-tools.py | 69 +++++++++++++++++++ 5 files changed, 96 insertions(+) create mode 100644 scripts/clang-tools/Makefile.clang-tools rename scripts/{ => clang-tools}/gen_compile_commands.py (100%) create mode 100755 scripts/clang-tools/run-clang-tools.py diff --git a/MAINTAINERS b/MAINTAINERS index 1d4aa7f942de..a444564e5572 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -4198,6 +4198,7 @@ W: https://clangbuiltlinux.github.io/ B: https://github.com/ClangBuiltLinux/linux/issues C: irc://chat.freenode.net/clangbuiltlinux F: Documentation/kbuild/llvm.rst +F: scripts/clang-tools/ K: \b(?i:clang|llvm)\b CLEANCACHE API diff --git a/Makefile b/Makefile index fe0164a654c7..3e2df010b342 100644 --- a/Makefile +++ b/Makefile @@ -747,6 +747,7 @@ KBUILD_CFLAGS += $(call cc-option,-fno-allow-store-data-races) include scripts/Makefile.kcov include scripts/Makefile.gcc-plugins +include scripts/clang-tools/Makefile.clang-tools ifdef CONFIG_READABLE_ASM # Disable optimizations that make assembler listings hard to read. @@ -1543,6 +1544,8 @@ help: @echo ' export_report - List the usages of all exported symbols' @echo ' headerdep - Detect inclusion cycles in headers' @echo ' coccicheck - Check with Coccinelle' + @echo ' clang-analyzer - Check with clang static analyzer' + @echo ' clang-tidy - Check with clang-tidy' @echo '' @echo 'Tools:' @echo ' nsdeps - Generate missing symbol namespace dependencies' diff --git a/scripts/clang-tools/Makefile.clang-tools b/scripts/clang-tools/Makefile.clang-tools new file mode 100644 index 000000000000..7ad3308c1937 --- /dev/null +++ b/scripts/clang-tools/Makefile.clang-tools @@ -0,0 +1,23 @@ +# SPDX-License-Identifier: GPL-2.0 +# +# Copyright (C) Google LLC, 2020 +# +# Author: Nathan Huckleberry +# +PHONY += clang-tidy +clang-tidy: +ifdef CONFIG_CC_IS_CLANG + $(PYTHON3) scripts/clang-tools/gen_compile_commands.py + $(PYTHON3) scripts/clang-tools/run-clang-tools.py clang-tidy compile_commands.json +else + $(error clang-tidy requires CC=clang) +endif + +PHONY += clang-analyzer +clang-analyzer: +ifdef CONFIG_CC_IS_CLANG + $(PYTHON3) scripts/clang-tools/gen_compile_commands.py + $(PYTHON3) scripts/clang-tools/run-clang-tools.py static-analyzer compile_commands.json +else + $(error clang-analyzer requires CC=clang) +endif diff --git a/scripts/gen_compile_commands.py b/scripts/clang-tools/gen_compile_commands.py similarity index 100% rename from scripts/gen_compile_commands.py rename to scripts/clang-tools/gen_compile_commands.py diff --git a/scripts/clang-tools/run-clang-tools.py b/scripts/clang-tools/run-clang-tools.py new file mode 100755 index 000000000000..00b8532c1729 --- /dev/null +++ b/scripts/clang-tools/run-clang-tools.py @@ -0,0 +1,69 @@ +#!/usr/bin/env python +# SPDX-License-Identifier: GPL-2.0 +# +# Copyright (C) Google LLC, 2020 +# +# Author: Nathan Huckleberry +# +"""A helper routine run clang-tidy and the clang static-analyzer on +compile_commands.json.""" + +import argparse +import json +import logging +import multiprocessing +import os +import subprocess +import sys + +def parse_arguments(): + """Set up and parses command-line arguments. + Returns: + args: Dict of parsed args + Has keys "file" and "type" + """ + usage = """Run clang-tidy or the clang static-analyzer on a + compilation database.""" + parser = argparse.ArgumentParser(description=usage) + + type_help = ("Type of analysis to be performed") + parser.add_argument("type", choices=["clang-tidy", "static-analyzer"], + help=type_help) + file_path_help = ("Path to the compilation database to parse") + parser.add_argument("file", type=str, help=file_path_help) + + args = parser.parse_args() + + return args + +def init(l,t): + global lock + global analysis_type + lock = l + analysis_type = t + +def run_analysis(entry): + filename = entry["file"] + checks = "-checks=-*,linuxkernel-*" if (analysis_type == "clang-tidy") else "-checks=-*,clang-analyzer-*" + p = subprocess.run(["clang-tidy", "-p", os.getcwd(), + checks, filename], + stdout=subprocess.PIPE, stderr=subprocess.STDOUT) + lock.acquire() + print(filename, file=sys.stderr) + sys.stderr.buffer.write(p.stdout) + lock.release() + + +def main(): + args = parse_arguments() + filename = args.file + + #Read JSON data into the datastore variable + with open(filename, "r") as f: + datastore = json.load(f) + lock = multiprocessing.Lock() + pool = multiprocessing.Pool(initializer=init, initargs=(lock, args.type)) + pool.map(run_analysis,datastore) + +if __name__ == "__main__": + main()