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=-11.3 required=3.0 tests=BAYES_00, 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 EBF41C433E7 for ; Thu, 15 Oct 2020 20:29:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 887F22074A for ; Thu, 15 Oct 2020 20:29:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732605AbgJOU3g (ORCPT ); Thu, 15 Oct 2020 16:29:36 -0400 Received: from mail2-relais-roc.national.inria.fr ([192.134.164.83]:4075 "EHLO mail2-relais-roc.national.inria.fr" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729482AbgJOU3g (ORCPT ); Thu, 15 Oct 2020 16:29:36 -0400 X-IronPort-AV: E=Sophos;i="5.77,380,1596492000"; d="scan'208";a="472841147" Received: from abo-173-121-68.mrs.modulonet.fr (HELO hadrien) ([85.68.121.173]) by mail2-relais-roc.national.inria.fr with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 15 Oct 2020 22:29:32 +0200 Date: Thu, 15 Oct 2020 22:29:31 +0200 (CEST) From: Julia Lawall X-X-Sender: jll@hadrien To: Sumera Priyadarsini cc: Gilles.Muller@lip6.fr, michal.lkml@markovi.net, nicolas.palix@imag.fr, cocci@systeme.lip6.fr, linux-kernel@vger.kernel.org Subject: Re: [Cocci] [PATCH V3] coccinelle: iterators: Add for_each_child.cocci script In-Reply-To: <20201015105140.sj4dfy2eykkts2tn@adolin> Message-ID: References: <20201015105140.sj4dfy2eykkts2tn@adolin> User-Agent: Alpine 2.22 (DEB 394 2020-01-19) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 15 Oct 2020, Sumera Priyadarsini wrote: > While iterating over child nodes with the for_each functions, if > control is transferred from the middle of the loop, as in the case > of a break or return or goto, there is no decrement in the > reference counter thus ultimately resulting in a memory leak. > > Add this script to detect potential memory leaks caused by > the absence of of_node_put() before break, goto, or, return > statements which transfer control outside the loop. > > Signed-off-by: Sumera Priyadarsini Applied, thanks. julia > > ---- > Changes in V2: > - Add options --include-headers and --no-includes > - Add 'when forall` to rules for break and goto > > Changes in V3: > - Add return case > --- > .../coccinelle/iterators/for_each_child.cocci | 358 ++++++++++++++++++ > 1 file changed, 358 insertions(+) > create mode 100644 scripts/coccinelle/iterators/for_each_child.cocci > > diff --git a/scripts/coccinelle/iterators/for_each_child.cocci b/scripts/coccinelle/iterators/for_each_child.cocci > new file mode 100644 > index 000000000000..bc394615948e > --- /dev/null > +++ b/scripts/coccinelle/iterators/for_each_child.cocci > @@ -0,0 +1,358 @@ > +// SPDX-License-Identifier: GPL-2.0-only > +// Adds missing of_node_put() before return/break/goto statement within a for_each iterator for child nodes. > +//# False positives can be due to function calls within the for_each > +//# loop that may encapsulate an of_node_put. > +/// > +// Confidence: High > +// Copyright: (C) 2020 Sumera Priyadarsini > +// URL: http://coccinelle.lip6.fr > +// Options: --no-includes --include-headers > + > +virtual patch > +virtual context > +virtual org > +virtual report > + > +@r@ > +local idexpression n; > +expression e1,e2; > +iterator name for_each_node_by_name, for_each_node_by_type, > +for_each_compatible_node, for_each_matching_node, > +for_each_matching_node_and_match, for_each_child_of_node, > +for_each_available_child_of_node, for_each_node_with_property; > +iterator i; > +statement S; > +expression list [n1] es; > +@@ > + > +( > +( > +for_each_node_by_name(n,e1) S > +| > +for_each_node_by_type(n,e1) S > +| > +for_each_compatible_node(n,e1,e2) S > +| > +for_each_matching_node(n,e1) S > +| > +for_each_matching_node_and_match(n,e1,e2) S > +| > +for_each_child_of_node(e1,n) S > +| > +for_each_available_child_of_node(e1,n) S > +| > +for_each_node_with_property(n,e1) S > +) > +& > +i(es,n,...) S > +) > + > +@ruleone depends on patch && !context && !org && !report@ > + > +local idexpression r.n; > +iterator r.i,i1; > +expression e; > +expression list [r.n1] es; > +statement S; > +@@ > + > + i(es,n,...) { > + ... > +( > + of_node_put(n); > +| > + e = n > +| > + return n; > +| > + i1(...,n,...) S > +| > +- return of_node_get(n); > ++ return n; > +| > ++ of_node_put(n); > +? return ...; > +) > + ... when any > + } > + > +@ruletwo depends on patch && !context && !org && !report@ > + > +local idexpression r.n; > +iterator r.i,i1,i2; > +expression e,e1; > +expression list [r.n1] es; > +statement S,S2; > +@@ > + > + i(es,n,...) { > + ... > +( > + of_node_put(n); > +| > + e = n > +| > + i1(...,n,...) S > +| > ++ of_node_put(n); > +? break; > +) > + ... when any > + } > +... when != n > + when strict > + when forall > +( > + n = e1; > +| > +?i2(...,n,...) S2 > +) > + > +@rulethree depends on patch && !context && !org && !report exists@ > + > +local idexpression r.n; > +iterator r.i,i1,i2; > +expression e,e1; > +identifier l; > +expression list [r.n1] es; > +statement S,S2; > +@@ > + > + i(es,n,...) { > + ... > +( > + of_node_put(n); > +| > + e = n > +| > + i1(...,n,...) S > +| > ++ of_node_put(n); > +? goto l; > +) > + ... when any > + } > +... when exists > +l: ... when != n > + when strict > + when forall > +( > + n = e1; > +| > +?i2(...,n,...) S2 > +) > + > +// ---------------------------------------------------------------------------- > + > +@ruleone_context depends on !patch && (context || org || report) exists@ > +statement S; > +expression e; > +expression list[r.n1] es; > +iterator r.i, i1; > +local idexpression r.n; > +position j0, j1; > +@@ > + > + i@j0(es,n,...) { > + ... > +( > + of_node_put(n); > +| > + e = n > +| > + return n; > +| > + i1(...,n,...) S > +| > + return @j1 ...; > +) > + ... when any > + } > + > +@ruleone_disj depends on !patch && (context || org || report)@ > +expression list[r.n1] es; > +iterator r.i; > +local idexpression r.n; > +position ruleone_context.j0, ruleone_context.j1; > +@@ > + > +* i@j0(es,n,...) { > + ... > +*return @j1...; > + ... when any > + } > + > +@ruletwo_context depends on !patch && (context || org || report) exists@ > +statement S, S2; > +expression e, e1; > +expression list[r.n1] es; > +iterator r.i, i1, i2; > +local idexpression r.n; > +position j0, j2; > +@@ > + > + i@j0(es,n,...) { > + ... > +( > + of_node_put(n); > +| > + e = n > +| > + i1(...,n,...) S > +| > + break@j2; > +) > + ... when any > + } > +... when != n > + when strict > + when forall > +( > + n = e1; > +| > +?i2(...,n,...) S2 > +) > + > +@ruletwo_disj depends on !patch && (context || org || report)@ > +statement S2; > +expression e1; > +expression list[r.n1] es; > +iterator r.i, i2; > +local idexpression r.n; > +position ruletwo_context.j0, ruletwo_context.j2; > +@@ > + > +* i@j0(es,n,...) { > + ... > +*break @j2; > + ... when any > + } > +... when != n > + when strict > + when forall > +( > + n = e1; > +| > +?i2(...,n,...) S2 > +) > + > +@rulethree_context depends on !patch && (context || org || report) exists@ > +identifier l; > +statement S,S2; > +expression e, e1; > +expression list[r.n1] es; > +iterator r.i, i1, i2; > +local idexpression r.n; > +position j0, j3; > +@@ > + > + i@j0(es,n,...) { > + ... > +( > + of_node_put(n); > +| > + e = n > +| > + i1(...,n,...) S > +| > + goto l@j3; > +) > + ... when any > + } > +... when exists > +l: > +... when != n > + when strict > + when forall > +( > + n = e1; > +| > +?i2(...,n,...) S2 > +) > + > +@rulethree_disj depends on !patch && (context || org || report) exists@ > +identifier l; > +statement S2; > +expression e1; > +expression list[r.n1] es; > +iterator r.i, i2; > +local idexpression r.n; > +position rulethree_context.j0, rulethree_context.j3; > +@@ > + > +* i@j0(es,n,...) { > + ... > +*goto l@j3; > + ... when any > + } > +... when exists > + l: > + ... when != n > + when strict > + when forall > +( > + n = e1; > +| > +?i2(...,n,...) S2 > +) > + > +// ---------------------------------------------------------------------------- > + > +@script:python ruleone_org depends on org@ > +i << r.i; > +j0 << ruleone_context.j0; > +j1 << ruleone_context. j1; > +@@ > + > +msg = "WARNING: Function \"%s\" should have of_node_put() before return " % (i) > +coccilib.org.print_safe_todo(j0[0], msg) > +coccilib.org.print_link(j1[0], "") > + > +@script:python ruletwo_org depends on org@ > +i << r.i; > +j0 << ruletwo_context.j0; > +j2 << ruletwo_context.j2; > +@@ > + > +msg = "WARNING: Function \"%s\" should have of_node_put() before break " % (i) > +coccilib.org.print_safe_todo(j0[0], msg) > +coccilib.org.print_link(j2[0], "") > + > +@script:python rulethree_org depends on org@ > +i << r.i; > +j0 << rulethree_context.j0; > +j3 << rulethree_context.j3; > +@@ > + > +msg = "WARNING: Function \"%s\" should have of_node_put() before goto " % (i) > +coccilib.org.print_safe_todo(j0[0], msg) > +coccilib.org.print_link(j3[0], "") > + > +// ---------------------------------------------------------------------------- > + > +@script:python ruleone_report depends on report@ > +i << r.i; > +j0 << ruleone_context.j0; > +j1 << ruleone_context.j1; > +@@ > + > +msg = "WARNING: Function \"%s\" should have of_node_put() before return around line %s." % (i, j1[0].line) > +coccilib.report.print_report(j0[0], msg) > + > +@script:python ruletwo_report depends on report@ > +i << r.i; > +j0 << ruletwo_context.j0; > +j2 << ruletwo_context.j2; > +@@ > + > +msg = "WARNING: Function \"%s\" should have of_node_put() before break around line %s." % (i,j2[0].line) > +coccilib.report.print_report(j0[0], msg) > + > +@script:python rulethree_report depends on report@ > +i << r.i; > +j0 << rulethree_context.j0; > +j3 << rulethree_context.j3; > +@@ > + > +msg = "WARNING: Function \"%s\" should have of_node_put() before goto around lines %s." % (i,j3[0].line) > +coccilib.report.print_report(j0[0], msg) > -- > 2.25.1 > > _______________________________________________ > Cocci mailing list > Cocci@systeme.lip6.fr > https://systeme.lip6.fr/mailman/listinfo/cocci >