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=-5.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 18D2BC43331 for ; Wed, 13 Nov 2019 08:10:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id ECD99214E0 for ; Wed, 13 Nov 2019 08:10:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726285AbfKMIKZ (ORCPT ); Wed, 13 Nov 2019 03:10:25 -0500 Received: from a.mx.secunet.com ([62.96.220.36]:34888 "EHLO a.mx.secunet.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725966AbfKMIKZ (ORCPT ); Wed, 13 Nov 2019 03:10:25 -0500 Received: from localhost (localhost [127.0.0.1]) by a.mx.secunet.com (Postfix) with ESMTP id 734C4200A7; Wed, 13 Nov 2019 09:10:24 +0100 (CET) X-Virus-Scanned: by secunet Received: from a.mx.secunet.com ([127.0.0.1]) by localhost (a.mx.secunet.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id HD8klcpCHdRG; Wed, 13 Nov 2019 09:10:24 +0100 (CET) Received: from mail-essen-01.secunet.de (mail-essen-01.secunet.de [10.53.40.204]) (using TLSv1 with cipher ECDHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by a.mx.secunet.com (Postfix) with ESMTPS id 057FE200A3; Wed, 13 Nov 2019 09:10:24 +0100 (CET) Received: from gauss2.secunet.de (10.182.7.193) by mail-essen-01.secunet.de (10.53.40.204) with Microsoft SMTP Server id 14.3.439.0; Wed, 13 Nov 2019 09:10:23 +0100 Received: by gauss2.secunet.de (Postfix, from userid 1000) id C137A3180095; Wed, 13 Nov 2019 09:10:21 +0100 (CET) Date: Wed, 13 Nov 2019 09:10:21 +0100 From: Steffen Klassert To: Xiaodong Xu CC: , , , Subject: Re: [PATCH v3] xfrm: release device reference for invalid state Message-ID: <20191113081021.GV13225@gauss3.secunet.de> References: <20191111230546.17105-1-stid.smth@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Disposition: inline In-Reply-To: <20191111230546.17105-1-stid.smth@gmail.com> User-Agent: Mutt/1.9.4 (2018-02-28) X-EXCLAIMER-MD-CONFIG: 2c86f778-e09b-4440-8b15-867914633a10 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Mon, Nov 11, 2019 at 03:05:46PM -0800, Xiaodong Xu wrote: > An ESP packet could be decrypted in async mode if the input handler for > this packet returns -EINPROGRESS in xfrm_input(). At this moment the device > reference in skb is held. Later xfrm_input() will be invoked again to > resume the processing. > If the transform state is still valid it would continue to release the > device reference and there won't be a problem; however if the transform > state is not valid when async resumption happens, the packet will be > dropped while the device reference is still being held. > When the device is deleted for some reason and the reference to this > device is not properly released, the kernel will keep logging like: > > unregister_netdevice: waiting for ppp2 to become free. Usage count = 1 > > The issue is observed when running IPsec traffic over a PPPoE device based > on a bridge interface. By terminating the PPPoE connection on the server > end for multiple times, the PPPoE device on the client side will eventually > get stuck on the above warning message. > > This patch will check the async mode first and continue to release device > reference in async resumption, before it is dropped due to invalid state. > > v2: Do not assign address family from outer_mode in the transform if the > state is invalid > > v3: Release device reference in the error path instead of jumping to resume > > Fixes: 4ce3dbe397d7b ("xfrm: Fix xfrm_input() to verify state is valid when (encap_type < 0)") > Signed-off-by: Xiaodong Xu > Reported-by: Bo Chen > Tested-by: Bo Chen Patch applied, thanks a lot!