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=-4.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,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 5FF1BC43441 for ; Sun, 11 Nov 2018 20:33:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1F6CD20871 for ; Sun, 11 Nov 2018 20:33:03 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1F6CD20871 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=decadent.org.uk Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730666AbeKLGWc (ORCPT ); Mon, 12 Nov 2018 01:22:32 -0500 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:50174 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730278AbeKLFsQ (ORCPT ); Mon, 12 Nov 2018 00:48:16 -0500 Received: from [192.168.4.242] (helo=deadeye) by shadbolt.decadent.org.uk with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.89) (envelope-from ) id 1gLvsc-0000l7-D7; Sun, 11 Nov 2018 19:58:46 +0000 Received: from ben by deadeye with local (Exim 4.91) (envelope-from ) id 1gLvsZ-0001ox-0w; Sun, 11 Nov 2018 19:58:43 +0000 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, "David S. Miller" , "Guillaume Nault" Date: Sun, 11 Nov 2018 19:49:05 +0000 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.16 309/366] l2tp: fix missing refcount drop in pppol2tp_tunnel_ioctl() In-Reply-To: X-SA-Exim-Connect-IP: 192.168.4.242 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 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.61-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Guillaume Nault commit f664e37dcc525768280cb94321424a09beb1c992 upstream. If 'session' is not NULL and is not a PPP pseudo-wire, then we fail to drop the reference taken by l2tp_session_get(). Fixes: ecd012e45ab5 ("l2tp: filter out non-PPP sessions in pppol2tp_tunnel_ioctl()") Signed-off-by: Guillaume Nault Signed-off-by: David S. Miller [bwh: Backported to 3.16: Also call session->deref in both cases] Signed-off-by: Ben Hutchings --- net/l2tp/l2tp_ppp.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) --- a/net/l2tp/l2tp_ppp.c +++ b/net/l2tp/l2tp_ppp.c @@ -1231,15 +1231,22 @@ static int pppol2tp_tunnel_ioctl(struct l2tp_session_get(sock_net(sk), tunnel, stats.session_id, true); - if (session && session->pwtype == L2TP_PWTYPE_PPP) { - err = pppol2tp_session_ioctl(session, cmd, - arg); + if (!session) { + err = -EBADR; + break; + } + if (session->pwtype != L2TP_PWTYPE_PPP) { if (session->deref) session->deref(session); l2tp_session_dec_refcount(session); - } else { err = -EBADR; + break; } + + err = pppol2tp_session_ioctl(session, cmd, arg); + if (session->deref) + session->deref(session); + l2tp_session_dec_refcount(session); break; } #ifdef CONFIG_XFRM