Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, David Ahern , Jiri Olsa , Kan Liang , Namhyung Kim , Peter Zijlstra , Arnaldo Carvalho de Melo Subject: [PATCH 4.9 12/25] perf header: Fix handling of PERF_EVENT_UPDATE__SCALE Date: Thu, 13 Jul 2017 17:40:26 +0200 Message-Id: <20170713154002.354512800@linuxfoundation.org> In-Reply-To: <20170713154001.535209166@linuxfoundation.org> References: <20170713154001.535209166@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: 4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Arnaldo Carvalho de Melo commit 8434a2ec13d5c8cb25716950bfbf7c9d7b64628a upstream. In commit daeecbc0c431 ("perf tools: Add event_update event scale type"), the handling of PERF_EVENT_UPDATE__SCALE cast struct event_update_event->data to a pointer to event_update_event_scale, uses some field from this casted struct and then ends up falling through to the handling of another event type, PERF_EVENT_UPDATE__CPUS were it casts that ev->data to yet another type, oops, fix it by inserting the missing break. Noticed when building perf using gcc 7 on Fedora Rawhide: util/header.c: In function 'perf_event__process_event_update': util/header.c:3207:16: error: this statement may fall through [-Werror=implicit-fallthrough=] evsel->scale = ev_scale->scale; ~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~ util/header.c:3208:2: note: here case PERF_EVENT_UPDATE__CPUS: ^~~~ This wasn't noticed because probably PERF_EVENT_UPDATE__CPUS comes after PERF_EVENT_UPDATE__SCALE, so we would just create a bogus evsel->own_cpus when processing a PERF_EVENT_UPDATE__SCALE to then leak it and create a new cpu map with the correct data. Cc: David Ahern Cc: Jiri Olsa Cc: Kan Liang Cc: Namhyung Kim Cc: Peter Zijlstra Fixes: daeecbc0c431 ("perf tools: Add event_update event scale type") Link: http://lkml.kernel.org/n/tip-lukcf9hdj092ax2914ss95at@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Greg Kroah-Hartman --- tools/perf/util/header.c | 1 + 1 file changed, 1 insertion(+) --- a/tools/perf/util/header.c +++ b/tools/perf/util/header.c @@ -3184,6 +3184,7 @@ int perf_event__process_event_update(str case PERF_EVENT_UPDATE__SCALE: ev_scale = (struct event_update_event_scale *) ev->data; evsel->scale = ev_scale->scale; + break; case PERF_EVENT_UPDATE__CPUS: ev_cpus = (struct event_update_event_cpus *) ev->data;