From patchwork Wed Jun 3 23:32:01 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kees Cook X-Patchwork-Id: 11586635 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 A78FC92A for ; Wed, 3 Jun 2020 23:32:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8FC55207D3 for ; Wed, 3 Jun 2020 23:32:28 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="fiQwobOm" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726636AbgFCXc1 (ORCPT ); Wed, 3 Jun 2020 19:32:27 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55644 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726462AbgFCXcX (ORCPT ); Wed, 3 Jun 2020 19:32:23 -0400 Received: from mail-pg1-x541.google.com (mail-pg1-x541.google.com [IPv6:2607:f8b0:4864:20::541]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 833F2C08C5C2 for ; Wed, 3 Jun 2020 16:32:19 -0700 (PDT) Received: by mail-pg1-x541.google.com with SMTP id r10so2654686pgv.8 for ; Wed, 03 Jun 2020 16:32:19 -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=OzsXBVjaZ9OyhsxAhNYMGGdoHV1Ey3EdXUcZrl9vzVM=; b=fiQwobOmB8JfoctwPcv9w7of7+WQd9TYcia/JYyZCbsrU9Y8/1P+jBMjyrycCzGPks k3E6rjY6DJsSHcxaDq1Tu7Q/DfBMxQ8rMeh/wfYcOaVB5kbniYqtcSsHt+OsYLHdKBZx t2PGOxXperAYxdbLB/SYYU6TMLn1K13kfox0Q= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=OzsXBVjaZ9OyhsxAhNYMGGdoHV1Ey3EdXUcZrl9vzVM=; b=tEpOgzkOF87Rm1j/FciQPS0Ph45IAKJiUCC9QXa+mVg7/Tq5hyhLZqzGV7snMlKG5e WxuR0pp+1Uan/mm+a1nL/MRY4VNzeBhmWDtyFqXhHU3uy25oS4ta+hnKe3IhmoeeU4Yi lITnUB35q9hBWJ9GtCyZ7/PriXbuYVKRVuEAKJKBPD5fMZC0qIjA3f/TMbySm4VBbSLo XDxbuPn36NkpDcSVAsFUpPxWnCb4jf5kTdF/H+vXx88sFnfz/fRU65hrdwLcgPNlUFs1 73e4QGZVLf1swi1p/+qXsBriyiyJFj/Pd4imWNpyJZu2ATiu7pNQ6zCiNpDDJWvRwcYS q5Jg== X-Gm-Message-State: AOAM531KgMcZzhFuK1emNL6KOlYrlwxOEL5rg3V7PVicMUZaAYkKYUdq haDwaEb3/OYr0hK+SdMj5B/B0g== X-Google-Smtp-Source: ABdhPJx+2U9hKaJOBj6eBoL3ylJxwEvHjFbKnopLLfUC+crlAi7qwt10Oa3/8CNVIO6wXkejTT/bbA== X-Received: by 2002:a62:27c6:: with SMTP id n189mr1466796pfn.277.1591227139068; Wed, 03 Jun 2020 16:32:19 -0700 (PDT) Received: from www.outflux.net (smtp.outflux.net. [198.145.64.163]) by smtp.gmail.com with ESMTPSA id x1sm2647707pfn.76.2020.06.03.16.32.15 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 03 Jun 2020 16:32:16 -0700 (PDT) From: Kees Cook To: linux-kernel@vger.kernel.org Cc: Kees Cook , Linus Torvalds , Miguel Ojeda , Alexander Potapenko , Joe Perches , Andy Whitcroft , x86@kernel.org, drbd-dev@lists.linbit.com, linux-block@vger.kernel.org, b43-dev@lists.infradead.org, netdev@vger.kernel.org, linux-wireless@vger.kernel.org, linux-ide@vger.kernel.org, linux-clk@vger.kernel.org, linux-spi@vger.kernel.org, linux-mm@kvack.org, clang-built-linux@googlegroups.com Subject: [PATCH 08/10] checkpatch: Remove awareness of uninitialized_var() macro Date: Wed, 3 Jun 2020 16:32:01 -0700 Message-Id: <20200603233203.1695403-9-keescook@chromium.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200603233203.1695403-1-keescook@chromium.org> References: <20200603233203.1695403-1-keescook@chromium.org> MIME-Version: 1.0 Sender: linux-clk-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-clk@vger.kernel.org Using uninitialized_var() is dangerous as it papers over real bugs[1] (or can in the future), and suppresses unrelated compiler warnings (e.g. "unused variable"). If the compiler thinks it is uninitialized, either simply initialize the variable or make compiler changes. In preparation for removing[2] the[3] macro[4], effectively revert commit 16b7f3c89907 ("checkpatch: avoid warning about uninitialized_var()") and remove all remaining mentions of uninitialized_var(). [1] https://lore.kernel.org/lkml/20200603174714.192027-1-glider@google.com/ [2] https://lore.kernel.org/lkml/CA+55aFw+Vbj0i=1TGqCR5vQkCzWJ0QxK6CernOU6eedsudAixw@mail.gmail.com/ [3] https://lore.kernel.org/lkml/CA+55aFwgbgqhbp1fkxvRKEpzyR5J8n1vKT1VZdz9knmPuXhOeg@mail.gmail.com/ [4] https://lore.kernel.org/lkml/CA+55aFz2500WfbKXAx8s67wrm9=yVJu65TpLgN_ybYNv0VEOKA@mail.gmail.com/ Signed-off-by: Kees Cook --- scripts/checkpatch.pl | 18 ++++++------------ 1 file changed, 6 insertions(+), 12 deletions(-) diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl index b83be177edf0..e9f8146600d0 100755 --- a/scripts/checkpatch.pl +++ b/scripts/checkpatch.pl @@ -838,7 +838,6 @@ our $FuncArg = qr{$Typecast{0,1}($LvalOrFunc|$Constant|$String)}; our $declaration_macros = qr{(?x: (?:$Storage\s+)?(?:[A-Z_][A-Z0-9]*_){0,2}(?:DEFINE|DECLARE)(?:_[A-Z0-9]+){1,6}\s*\(| (?:$Storage\s+)?[HLP]?LIST_HEAD\s*\(| - (?:$Storage\s+)?${Type}\s+uninitialized_var\s*\(| (?:SKCIPHER_REQUEST|SHASH_DESC|AHASH_REQUEST)_ON_STACK\s*\( )}; @@ -4075,7 +4074,7 @@ sub process { } # check for function declarations without arguments like "int foo()" - if ($line =~ /(\b$Type\s*$Ident)\s*\(\s*\)/) { + if ($line =~ /(\b$Type\s+$Ident)\s*\(\s*\)/) { if (ERROR("FUNCTION_WITHOUT_ARGS", "Bad function definition - $1() should probably be $1(void)\n" . $herecurr) && $fix) { @@ -6271,8 +6270,7 @@ sub process { if (defined $cond) { substr($s, 0, length($cond), ''); } - if ($s =~ /^\s*;/ && - $function_name ne 'uninitialized_var') + if ($s =~ /^\s*;/) { WARN("AVOID_EXTERNS", "externs should be avoided in .c files\n" . $herecurr); @@ -6291,17 +6289,13 @@ sub process { } # check for function declarations that have arguments without identifier names -# while avoiding uninitialized_var(x) if (defined $stat && - $stat =~ /^.\s*(?:extern\s+)?$Type\s*(?:($Ident)|\(\s*\*\s*$Ident\s*\))\s*\(\s*([^{]+)\s*\)\s*;/s && - (!defined($1) || - (defined($1) && $1 ne "uninitialized_var")) && - $2 ne "void") { - my $args = trim($2); + $stat =~ /^.\s*(?:extern\s+)?$Type\s*(?:$Ident|\(\s*\*\s*$Ident\s*\))\s*\(\s*([^{]+)\s*\)\s*;/s && + $1 ne "void") { + my $args = trim($1); while ($args =~ m/\s*($Type\s*(?:$Ident|\(\s*\*\s*$Ident?\s*\)\s*$balanced_parens)?)/g) { my $arg = trim($1); - if ($arg =~ /^$Type$/ && - $arg !~ /enum\s+$Ident$/) { + if ($arg =~ /^$Type$/ && $arg !~ /enum\s+$Ident$/) { WARN("FUNCTION_ARGUMENTS", "function definition argument '$arg' should also have an identifier name\n" . $herecurr); }