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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id A75A9C001DB for ; Sat, 5 Aug 2023 14:01:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229493AbjHEOB4 (ORCPT ); Sat, 5 Aug 2023 10:01:56 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45108 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229379AbjHEOBy (ORCPT ); Sat, 5 Aug 2023 10:01:54 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CCAD7113 for ; Sat, 5 Aug 2023 07:01:53 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 423D360E0A for ; Sat, 5 Aug 2023 14:01:53 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id DD57BC433C8; Sat, 5 Aug 2023 14:01:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1691244112; bh=Z7i5QwWx2AHjf62kHkBY4DZ84VJ8f4fULqWvP9CNS3w=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=aYGafcyMpqWW1JrU2tEUIbghx9oeVRHe7yD/V4AonUVl9pJjX0qPNmFahIeoYGmqS lNxfBmxJyFNJ10LzTVvlN3atGc3gqXnrcIvdjeFWa/RKNk1B/gge20DGMKPN/Mlybb U296FuomHsXqJ8T3sGxR05iuz7UZ5xWTaQiZIZmGJmgw36ljpE5Az3nrJ9OfGYtUkK cWSOAgFnN9klCvWYx0ETFfHI1NcA2L0SkgjawfD6hcidieBpgxzj+i054aC7LxTEZy KCBS/2SgOsDUItr7bXGoU0TPnWYtHa1gkNUV7Qch4SI2eyHwq7yICHzRSEbVCHC7A3 yBhDOLAuLqqDg== Date: Sat, 5 Aug 2023 23:01:48 +0900 From: Masami Hiramatsu (Google) To: Arnaldo Carvalho de Melo Cc: Adrian Hunter , Ian Rogers , Jiri Olsa , Namhyung Kim , Linux Kernel Mailing List Subject: Re: [PATCH 1/1] perf probe: Free string returned by synthesize_perf_probe_point() on failure to add a probe Message-Id: <20230805230148.84a94f9f67e56513d58f4e1b@kernel.org> In-Reply-To: References: X-Mailer: Sylpheed 3.7.0 (GTK+ 2.24.33; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 4 Aug 2023 13:22:44 -0300 Arnaldo Carvalho de Melo wrote: > Building perf with EXTRA_CFLAGS="-fsanitize=address" a leak is detect > when trying to add a probe to a non-existent function: > > # perf probe -x ~/bin/perf dso__neW > Probe point 'dso__neW' not found. > Error: Failed to add events. > > ================================================================= > ==296634==ERROR: LeakSanitizer: detected memory leaks > > Direct leak of 128 byte(s) in 1 object(s) allocated from: > #0 0x7f67642ba097 in calloc (/lib64/libasan.so.8+0xba097) > #1 0x7f67641a76f1 in allocate_cfi (/lib64/libdw.so.1+0x3f6f1) > > Direct leak of 65 byte(s) in 1 object(s) allocated from: > #0 0x7f67642b95b5 in __interceptor_realloc.part.0 (/lib64/libasan.so.8+0xb95b5) > #1 0x6cac75 in strbuf_grow util/strbuf.c:64 > #2 0x6ca934 in strbuf_init util/strbuf.c:25 > #3 0x9337d2 in synthesize_perf_probe_point util/probe-event.c:2018 > #4 0x92be51 in try_to_find_probe_trace_events util/probe-event.c:964 > #5 0x93d5c6 in convert_to_probe_trace_events util/probe-event.c:3512 > #6 0x93d6d5 in convert_perf_probe_events util/probe-event.c:3529 > #7 0x56f37f in perf_add_probe_events /var/home/acme/git/perf-tools-next/tools/perf/builtin-probe.c:354 > #8 0x572fbc in __cmd_probe /var/home/acme/git/perf-tools-next/tools/perf/builtin-probe.c:738 > #9 0x5730f2 in cmd_probe /var/home/acme/git/perf-tools-next/tools/perf/builtin-probe.c:766 > #10 0x635d81 in run_builtin /var/home/acme/git/perf-tools-next/tools/perf/perf.c:323 > #11 0x6362c1 in handle_internal_command /var/home/acme/git/perf-tools-next/tools/perf/perf.c:377 > #12 0x63667a in run_argv /var/home/acme/git/perf-tools-next/tools/perf/perf.c:421 > #13 0x636b8d in main /var/home/acme/git/perf-tools-next/tools/perf/perf.c:537 > #14 0x7f676302950f in __libc_start_call_main (/lib64/libc.so.6+0x2950f) > > SUMMARY: AddressSanitizer: 193 byte(s) leaked in 2 allocation(s). > # > > synthesize_perf_probe_point() returns a "detached" strbuf, i.e. a > malloc'ed string that needs to be free'd. > > An audit will be performed to find other such cases. Thanks for finding it! Acked-by: Masami Hiramatsu (Google) > > Cc: Adrian Hunter > Cc: Ian Rogers > Cc: Jiri Olsa > Cc: Masami Hiramatsu > Cc: Namhyung Kim > Link: https://lore.kernel.org/lkml/ > Signed-off-by: Arnaldo Carvalho de Melo > --- > tools/perf/util/probe-event.c | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) > > diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c > index 2d056f02ae408a64..c7bfeab610a3679a 100644 > --- a/tools/perf/util/probe-event.c > +++ b/tools/perf/util/probe-event.c > @@ -961,8 +961,9 @@ static int try_to_find_probe_trace_events(struct perf_probe_event *pev, > debuginfo__delete(dinfo); > > if (ntevs == 0) { /* No error but failed to find probe point. */ > - pr_warning("Probe point '%s' not found.\n", > - synthesize_perf_probe_point(&pev->point)); > + char *probe_point = synthesize_perf_probe_point(&pev->point); > + pr_warning("Probe point '%s' not found.\n", probe_point); > + free(probe_point); > return -ENODEV; > } else if (ntevs < 0) { > /* Error path : ntevs < 0 */ > -- > 2.37.1 > -- Masami Hiramatsu (Google)