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=-5.7 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS, UNWANTED_LANGUAGE_BODY,USER_AGENT_MUTT 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 A2AC8C43381 for ; Thu, 14 Feb 2019 08:34:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 70E1E2229F for ; Thu, 14 Feb 2019 08:34:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2394678AbfBNIeQ (ORCPT ); Thu, 14 Feb 2019 03:34:16 -0500 Received: from mx1.redhat.com ([209.132.183.28]:25240 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2394645AbfBNIeP (ORCPT ); Thu, 14 Feb 2019 03:34:15 -0500 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id B9022A0B42; Thu, 14 Feb 2019 08:34:15 +0000 (UTC) Received: from krava (unknown [10.43.17.161]) by smtp.corp.redhat.com (Postfix) with SMTP id E92B154500; Thu, 14 Feb 2019 08:34:12 +0000 (UTC) Date: Thu, 14 Feb 2019 09:34:11 +0100 From: Jiri Olsa To: Bo YU Cc: peterz@infradead.org, mingo@redhat.com, acme@kernel.org, alexander.shishkin@linux.intel.com, namhyung@kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] perf trace: Fix potential USE_AFTER_FREE problem Message-ID: <20190214083411.GA25842@krava> References: <20190214052356.26884-1-tsu.yubo@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190214052356.26884-1-tsu.yubo@gmail.com> User-Agent: Mutt/1.10.1 (2018-07-13) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.26]); Thu, 14 Feb 2019 08:34:15 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Feb 14, 2019 at 12:23:56AM -0500, Bo YU wrote: > From: Bo Yu > > There is a freed pointer "evsel", so fix it. > > Detected by CoverityScan, CID#1442595("Memory-illegalaccesses > (USE_AFTER_FREE)") > Fixes: 6ab3bc240ade4("perf trace: Support multiple "vfs_getname" probes") > > Signed-off-by: Bo Yu > --- > tools/perf/builtin-trace.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/tools/perf/builtin-trace.c b/tools/perf/builtin-trace.c > index b36061cd1ab8..4036b20a1067 100644 > --- a/tools/perf/builtin-trace.c > +++ b/tools/perf/builtin-trace.c > @@ -2515,7 +2515,7 @@ static size_t trace__fprintf_thread_summary(struct trace *trace, FILE *fp); > static bool perf_evlist__add_vfs_getname(struct perf_evlist *evlist) > { > bool found = false; > - struct perf_evsel *evsel, *tmp; > + struct perf_evsel *evsel = NULL, *tmp; hum, I can't see how this change could matter, could you pelase explain? jirka > struct parse_events_error err = { .idx = 0, }; > int ret = parse_events(evlist, "probe:vfs_getname*", &err); > > -- > 2.11.0 >