From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755213AbdBOXWc (ORCPT ); Wed, 15 Feb 2017 18:22:32 -0500 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:53812 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752721AbdBOXW3 (ORCPT ); Wed, 15 Feb 2017 18:22:29 -0500 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Ingo Molnar" , vince@deater.net, dvyukov@google.com, "Arnaldo Carvalho de Melo" , "Alexander Shishkin" , sasha.levin@oracle.com, oleg@redhat.com, "Peter Zijlstra" , "Thomas Gleixner" , panand@redhat.com, "Jiri Olsa" , eranian@google.com, "Linus Torvalds" Date: Wed, 15 Feb 2017 22:41:34 +0000 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.2 113/126] perf: Do not double free In-Reply-To: X-SA-Exim-Connect-IP: 2a02:8011:400e:2:6f00:88c8:c921:d332 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.2.85-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Peter Zijlstra commit 130056275ade730e7a79c110212c8815202773ee upstream. In case of: err_file: fput(event_file), we'll end up calling perf_release() which in turn will free the event. Do not then free the event _again_. Tested-by: Alexander Shishkin Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Alexander Shishkin Cc: Arnaldo Carvalho de Melo Cc: Jiri Olsa Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: dvyukov@google.com Cc: eranian@google.com Cc: oleg@redhat.com Cc: panand@redhat.com Cc: sasha.levin@oracle.com Cc: vince@deater.net Link: http://lkml.kernel.org/r/20160224174947.697350349@infradead.org Signed-off-by: Ingo Molnar [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings --- kernel/events/core.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -6741,7 +6741,12 @@ err_context: perf_unpin_context(ctx); put_ctx(ctx); err_alloc: - free_event(event); + /* + * If event_file is set, the fput() above will have called ->release() + * and that will take care of freeing the event. + */ + if (!event_file) + free_event(event); err_task: if (task) put_task_struct(task);