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=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,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 5CF45C433E0 for ; Wed, 24 Jun 2020 19:42:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3AFE62077D for ; Wed, 24 Jun 2020 19:42:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2406182AbgFXTmj (ORCPT ); Wed, 24 Jun 2020 15:42:39 -0400 Received: from mail3-relais-sop.national.inria.fr ([192.134.164.104]:28390 "EHLO mail3-relais-sop.national.inria.fr" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2404915AbgFXTmi (ORCPT ); Wed, 24 Jun 2020 15:42:38 -0400 X-IronPort-AV: E=Sophos;i="5.75,276,1589234400"; d="scan'208";a="352641912" Received: from abo-173-121-68.mrs.modulonet.fr (HELO hadrien) ([85.68.121.173]) by mail3-relais-sop.national.inria.fr with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 24 Jun 2020 21:42:34 +0200 Date: Wed, 24 Jun 2020 21:42:34 +0200 (CEST) From: Julia Lawall X-X-Sender: jll@hadrien To: Denis Efremov cc: cocci@systeme.lip6.fr, linux-kernel@vger.kernel.org Subject: Re: [PATCH v4] coccinelle: misc: add array_size_dup script to detect missed overflow checks In-Reply-To: <20200622221056.34241-1-efremov@linux.com> Message-ID: References: <20200615102045.4558-1-efremov@linux.com> <20200622221056.34241-1-efremov@linux.com> User-Agent: Alpine 2.22 (DEB 394 2020-01-19) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 23 Jun 2020, Denis Efremov wrote: > Detect an opencoded expression that is used before or after > array_size()/array3_size()/struct_size() to compute the same size. > > Signed-off-by: Denis Efremov Applied, thanks. julia > --- > Changes in v2: > - python rules moved next to SmPL patterns > - assignment operator used > - struct_size patterns fixed to check only E3, since > E1, E2 are sizeofs of a structure and a member > of a structure > Changes in v3: > - s/overlow/overflow/ typo fixed (thanks, Markus) > - \(&E1\|&E2\) changed to &\(E1\|E2\) > - print strings breaks removed > Changes in v4: > - duplicates warning removed > - python2 compatability in report&&org modes added > - s/down the code/later/ warning changed > - \(E1\|E2\|subE1\|subE2\) patterns simplified to \(subE1\|subE2\) > > scripts/coccinelle/misc/array_size_dup.cocci | 209 +++++++++++++++++++ > 1 file changed, 209 insertions(+) > create mode 100644 scripts/coccinelle/misc/array_size_dup.cocci > > diff --git a/scripts/coccinelle/misc/array_size_dup.cocci b/scripts/coccinelle/misc/array_size_dup.cocci > new file mode 100644 > index 000000000000..d3d635b2d4fc > --- /dev/null > +++ b/scripts/coccinelle/misc/array_size_dup.cocci > @@ -0,0 +1,209 @@ > +// SPDX-License-Identifier: GPL-2.0-only > +/// > +/// Check for array_size(), array3_size(), struct_size() duplicates. > +/// Three types of patterns for these functions: > +/// 1. An opencoded expression is used before array_size() to compute the same size > +/// 2. An opencoded expression is used after array_size() to compute the same size > +/// From security point of view only first case is relevant. These functions > +/// perform arithmetic overflow check. Thus, if we use an opencoded expression > +/// before a call to the *_size() function we can miss an overflow. > +/// > +// Confidence: High > +// Copyright: (C) 2020 Denis Efremov ISPRAS > +// Options: --no-includes --include-headers --no-loops > + > +virtual context > +virtual report > +virtual org > + > +@as@ > +expression E1, E2; > +@@ > + > +array_size(E1, E2) > + > +@as_next@ > +expression subE1 <= as.E1; > +expression subE2 <= as.E2; > +expression as.E1, as.E2, E3; > +assignment operator aop; > +position p1, p2; > +@@ > + > +* E1 * E2@p1 > + ... when != \(subE1\|subE2\) aop E3 > + when != &\(subE1\|subE2\) > +* array_size(E1, E2)@p2 > + > +@script:python depends on report@ > +p1 << as_next.p1; > +p2 << as_next.p2; > +@@ > + > +msg = "WARNING: array_size is used later (line %s) to compute the same size" % (p2[0].line) > +coccilib.report.print_report(p1[0], msg) > + > +@script:python depends on org@ > +p1 << as_next.p1; > +p2 << as_next.p2; > +@@ > + > +msg = "WARNING: array_size is used later (line %s) to compute the same size" % (p2[0].line) > +coccilib.org.print_todo(p1[0], msg) > + > +@as_prev@ > +expression subE1 <= as.E1; > +expression subE2 <= as.E2; > +expression as.E1, as.E2, E3; > +assignment operator aop; > +position p1, p2; > +@@ > + > +* array_size(E1, E2)@p1 > + ... when != \(subE1\|subE2\) aop E3 > + when != &\(subE1\|subE2\) > +* E1 * E2@p2 > + > +@script:python depends on report@ > +p1 << as_prev.p1; > +p2 << as_prev.p2; > +@@ > + > +msg = "WARNING: array_size is already used (line %s) to compute the same size" % (p1[0].line) > +coccilib.report.print_report(p2[0], msg) > + > +@script:python depends on org@ > +p1 << as_prev.p1; > +p2 << as_prev.p2; > +@@ > + > +msg = "WARNING: array_size is already used (line %s) to compute the same size" % (p1[0].line) > +coccilib.org.print_todo(p2[0], msg) > + > +@as3@ > +expression E1, E2, E3; > +@@ > + > +array3_size(E1, E2, E3) > + > +@as3_next@ > +expression subE1 <= as3.E1; > +expression subE2 <= as3.E2; > +expression subE3 <= as3.E3; > +expression as3.E1, as3.E2, as3.E3, E4; > +assignment operator aop; > +position p1, p2; > +@@ > + > +* E1 * E2 * E3@p1 > + ... when != \(subE1\|subE2\|subE3\) aop E4 > + when != &\(subE1\|subE2\|subE3\) > +* array3_size(E1, E2, E3)@p2 > + > +@script:python depends on report@ > +p1 << as3_next.p1; > +p2 << as3_next.p2; > +@@ > + > +msg = "WARNING: array3_size is used later (line %s) to compute the same size" % (p2[0].line) > +coccilib.report.print_report(p1[0], msg) > + > +@script:python depends on org@ > +p1 << as3_next.p1; > +p2 << as3_next.p2; > +@@ > + > +msg = "WARNING: array3_size is used later (line %s) to compute the same size" % (p2[0].line) > +coccilib.org.print_todo(p1[0], msg) > + > +@as3_prev@ > +expression subE1 <= as3.E1; > +expression subE2 <= as3.E2; > +expression subE3 <= as3.E3; > +expression as3.E1, as3.E2, as3.E3, E4; > +assignment operator aop; > +position p1, p2; > +@@ > + > +* array3_size(E1, E2, E3)@p1 > + ... when != \(subE1\|subE2\|subE3\) aop E4 > + when != &\(subE1\|subE2\|subE3\) > +* E1 * E2 * E3@p2 > + > +@script:python depends on report@ > +p1 << as3_prev.p1; > +p2 << as3_prev.p2; > +@@ > + > +msg = "WARNING: array3_size is already used (line %s) to compute the same size" % (p1[0].line) > +coccilib.report.print_report(p2[0], msg) > + > +@script:python depends on org@ > +p1 << as3_prev.p1; > +p2 << as3_prev.p2; > +@@ > + > +msg = "WARNING: array3_size is already used (line %s) to compute the same size" % (p1[0].line) > +coccilib.org.print_todo(p2[0], msg) > + > +@ss@ > +expression E1, E2, E3; > +@@ > + > +struct_size(E1, E2, E3) > + > +@ss_next@ > +expression subE3 <= ss.E3; > +expression ss.E1, ss.E2, ss.E3, E4; > +assignment operator aop; > +position p1, p2; > +@@ > + > +* E1 * E2 + E3@p1 > + ... when != subE3 aop E4 > + when != &subE3 > +* struct_size(E1, E2, E3)@p2 > + > +@script:python depends on report@ > +p1 << ss_next.p1; > +p2 << ss_next.p2; > +@@ > + > +msg = "WARNING: struct_size is used later (line %s) to compute the same size" % (p2[0].line) > +coccilib.report.print_report(p1[0], msg) > + > +@script:python depends on org@ > +p1 << ss_next.p1; > +p2 << ss_next.p2; > +@@ > + > +msg = "WARNING: struct_size is used later (line %s) to compute the same size" % (p2[0].line) > +coccilib.org.print_todo(p1[0], msg) > + > +@ss_prev@ > +expression subE3 <= ss.E3; > +expression ss.E1, ss.E2, ss.E3, E4; > +assignment operator aop; > +position p1, p2; > +@@ > + > +* struct_size(E1, E2, E3)@p1 > + ... when != subE3 aop E4 > + when != &subE3 > +* E1 * E2 + E3@p2 > + > +@script:python depends on report@ > +p1 << ss_prev.p1; > +p2 << ss_prev.p2; > +@@ > + > +msg = "WARNING: struct_size is already used (line %s) to compute the same size" % (p1[0].line) > +coccilib.report.print_report(p2[0], msg) > + > +@script:python depends on org@ > +p1 << ss_prev.p1; > +p2 << ss_prev.p2; > +@@ > + > +msg = "WARNING: struct_size is already used (line %s) to compute the same size" % (p1[0].line) > +coccilib.org.print_todo(p2[0], msg) > -- > 2.26.2 > >