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=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED 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 BD9F5C04AB6 for ; Tue, 28 May 2019 15:48:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 90EFA21473 for ; Tue, 28 May 2019 15:48:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726719AbfE1PsY (ORCPT ); Tue, 28 May 2019 11:48:24 -0400 Received: from mail.kernel.org ([198.145.29.99]:57080 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726243AbfE1PsY (ORCPT ); Tue, 28 May 2019 11:48:24 -0400 Received: from gandalf.local.home (cpe-66-24-58-225.stny.res.rr.com [66.24.58.225]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 864E82133F; Tue, 28 May 2019 15:48:23 +0000 (UTC) Date: Tue, 28 May 2019 11:48:21 -0400 From: Steven Rostedt To: Tomas Bortoli Cc: linux-kernel@vger.kernel.org, mingo@redhat.com Subject: Re: [PATCH] trace: Avoid memory leak in predicate_parse() Message-ID: <20190528114821.2302dabd@gandalf.local.home> In-Reply-To: <20190528154338.29976-1-tomasbortoli@gmail.com> References: <20190528104400.388e4c3f@gandalf.local.home> <20190528154338.29976-1-tomasbortoli@gmail.com> X-Mailer: Claws Mail 3.17.3 (GTK+ 2.24.32; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 28 May 2019 17:43:38 +0200 Tomas Bortoli wrote: > In case of errors, predicate_parse() goes to the out_free label > to free memory and to return an error code. > > However, predicate_parse() does not free the predicates of the > temporary prog_stack array, thence leaking them. Thanks, I applied this and I'm running it through my tests. But just an FYI, when sending updated patches please add a "v2" to the subject: [PATCH v2] tracing: Avoid memory leak in predicate_parse() That way struggling maintainers like myself don't get confused about which patch to apply ;-) Thanks! -- Steve > > Signed-off-by: Tomas Bortoli > Reported-by: syzbot+6b8e0fb820e570c59e19@syzkaller.appspotmail.com > --- > kernel/trace/trace_events_filter.c | 4 +++- > 1 file changed, 3 insertions(+), 1 deletion(-) > > diff --git a/kernel/trace/trace_events_filter.c b/kernel/trace/trace_events_filter.c > index 05a66493a164..ecfa6f0f1c7e 100644 > --- a/kernel/trace/trace_events_filter.c > +++ b/kernel/trace/trace_events_filter.c > @@ -427,7 +427,7 @@ predicate_parse(const char *str, int nr_parens, int nr_preds, > op_stack = kmalloc_array(nr_parens, sizeof(*op_stack), GFP_KERNEL); > if (!op_stack) > return ERR_PTR(-ENOMEM); > - prog_stack = kmalloc_array(nr_preds, sizeof(*prog_stack), GFP_KERNEL); > + prog_stack = kcalloc(nr_preds, sizeof(*prog_stack), GFP_KERNEL); > if (!prog_stack) { > parse_error(pe, -ENOMEM, 0); > goto out_free; > @@ -578,6 +578,8 @@ predicate_parse(const char *str, int nr_parens, int nr_preds, > out_free: > kfree(op_stack); > kfree(inverts); > + for (i = 0; prog_stack[i].pred; i++) > + kfree(prog_stack[i].pred); > kfree(prog_stack); > return ERR_PTR(ret); > }