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=-16.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 D38BAC433E6 for ; Mon, 15 Mar 2021 13:29:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7F97E64EEB for ; Mon, 15 Mar 2021 13:29:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229814AbhCON2w (ORCPT ); Mon, 15 Mar 2021 09:28:52 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:51082 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230433AbhCON2S (ORCPT ); Mon, 15 Mar 2021 09:28:18 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1615814898; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=lyVS2XKGdVlt6gqn+kMGdjYoFHIFbevN4UzUZHMFXJE=; b=MxHwTpmNzfV9bNQl3x/B2oSbR6+2VJVjxss5pOtbkGo+aXWYWukurk5KTbKcMTGQhGff1X gqiVb4gLRMDEDCb+3W4OLiKJouAD/0v2VbJM3QKJPZsEKmpJYxxw5Vz2vlrbVf+H36H2BD d6F/gThsaaNb5qrs2CnfKtS7UPNnyWk= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-511-7m-AxzihO5uxOoHB4C3M6w-1; Mon, 15 Mar 2021 09:28:13 -0400 X-MC-Unique: 7m-AxzihO5uxOoHB4C3M6w-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 1E46A108BD06; Mon, 15 Mar 2021 13:28:12 +0000 (UTC) Received: from krava (unknown [10.40.196.50]) by smtp.corp.redhat.com (Postfix) with SMTP id 32DBF610F0; Mon, 15 Mar 2021 13:28:10 +0000 (UTC) Date: Mon, 15 Mar 2021 14:28:09 +0100 From: Jiri Olsa To: Namhyung Kim Cc: Arnaldo Carvalho de Melo , Ingo Molnar , Peter Zijlstra , Mark Rutland , Alexander Shishkin , LKML , Andi Kleen , Ian Rogers Subject: Re: [PATCH] perf record: Fix memory leak in vDSO Message-ID: References: <20210315045641.700430-1-namhyung@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210315045641.700430-1-namhyung@kernel.org> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Mar 15, 2021 at 01:56:41PM +0900, Namhyung Kim wrote: > I got several memory leak reports from Asan with a simple command. It > was because VDSO is not released due to the refcount. Like in > __dsos_addnew_id(), it should put the refcount after adding to the list. > > $ perf record true > [ perf record: Woken up 1 times to write data ] > [ perf record: Captured and wrote 0.030 MB perf.data (10 samples) ] > > ================================================================= > ==692599==ERROR: LeakSanitizer: detected memory leaks > > Direct leak of 439 byte(s) in 1 object(s) allocated from: > #0 0x7fea52341037 in __interceptor_calloc ../../../../src/libsanitizer/asan/asan_malloc_linux.cpp:154 > #1 0x559bce4aa8ee in dso__new_id util/dso.c:1256 > #2 0x559bce59245a in __machine__addnew_vdso util/vdso.c:132 > #3 0x559bce59245a in machine__findnew_vdso util/vdso.c:347 > #4 0x559bce50826c in map__new util/map.c:175 > #5 0x559bce503c92 in machine__process_mmap2_event util/machine.c:1787 > #6 0x559bce512f6b in machines__deliver_event util/session.c:1481 > #7 0x559bce515107 in perf_session__deliver_event util/session.c:1551 > #8 0x559bce51d4d2 in do_flush util/ordered-events.c:244 > #9 0x559bce51d4d2 in __ordered_events__flush util/ordered-events.c:323 > #10 0x559bce519bea in __perf_session__process_events util/session.c:2268 > #11 0x559bce519bea in perf_session__process_events util/session.c:2297 > #12 0x559bce2e7a52 in process_buildids /home/namhyung/project/linux/tools/perf/builtin-record.c:1017 > #13 0x559bce2e7a52 in record__finish_output /home/namhyung/project/linux/tools/perf/builtin-record.c:1234 > #14 0x559bce2ed4f6 in __cmd_record /home/namhyung/project/linux/tools/perf/builtin-record.c:2026 > #15 0x559bce2ed4f6 in cmd_record /home/namhyung/project/linux/tools/perf/builtin-record.c:2858 > #16 0x559bce422db4 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:313 > #17 0x559bce2acac8 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:365 > #18 0x559bce2acac8 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:409 > #19 0x559bce2acac8 in main /home/namhyung/project/linux/tools/perf/perf.c:539 > #20 0x7fea51e76d09 in __libc_start_main ../csu/libc-start.c:308 > > Indirect leak of 32 byte(s) in 1 object(s) allocated from: > #0 0x7fea52341037 in __interceptor_calloc ../../../../src/libsanitizer/asan/asan_malloc_linux.cpp:154 > #1 0x559bce520907 in nsinfo__copy util/namespaces.c:169 > #2 0x559bce50821b in map__new util/map.c:168 > #3 0x559bce503c92 in machine__process_mmap2_event util/machine.c:1787 > #4 0x559bce512f6b in machines__deliver_event util/session.c:1481 > #5 0x559bce515107 in perf_session__deliver_event util/session.c:1551 > #6 0x559bce51d4d2 in do_flush util/ordered-events.c:244 > #7 0x559bce51d4d2 in __ordered_events__flush util/ordered-events.c:323 > #8 0x559bce519bea in __perf_session__process_events util/session.c:2268 > #9 0x559bce519bea in perf_session__process_events util/session.c:2297 > #10 0x559bce2e7a52 in process_buildids /home/namhyung/project/linux/tools/perf/builtin-record.c:1017 > #11 0x559bce2e7a52 in record__finish_output /home/namhyung/project/linux/tools/perf/builtin-record.c:1234 > #12 0x559bce2ed4f6 in __cmd_record /home/namhyung/project/linux/tools/perf/builtin-record.c:2026 > #13 0x559bce2ed4f6 in cmd_record /home/namhyung/project/linux/tools/perf/builtin-record.c:2858 > #14 0x559bce422db4 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:313 > #15 0x559bce2acac8 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:365 > #16 0x559bce2acac8 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:409 > #17 0x559bce2acac8 in main /home/namhyung/project/linux/tools/perf/perf.c:539 > #18 0x7fea51e76d09 in __libc_start_main ../csu/libc-start.c:308 > > SUMMARY: AddressSanitizer: 471 byte(s) leaked in 2 allocation(s). > > Signed-off-by: Namhyung Kim > --- > tools/perf/util/vdso.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/tools/perf/util/vdso.c b/tools/perf/util/vdso.c > index 3cc91ad048ea..43beb169631d 100644 > --- a/tools/perf/util/vdso.c > +++ b/tools/perf/util/vdso.c > @@ -133,6 +133,8 @@ static struct dso *__machine__addnew_vdso(struct machine *machine, const char *s > if (dso != NULL) { > __dsos__add(&machine->dsos, dso); > dso__set_long_name(dso, long_name, false); > + /* Put dso here because __dsos_add already got it */ > + dso__put(dso); from quick look I don't understand why we take refcnt down right after adding to the list.. it would make sense to me if dso is not stored elsewhere so we want dsos__exit to release it.. but it's still stored in map object I checked and we do extra dso__get in machine__findnew_vdso (and also in dsos__findnew_id) ... so that one seems to me like the one we should remove but I might be missing something, I'll try to check more deeply later on jirka