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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id AD655C433FE for ; Wed, 23 Nov 2022 09:10:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237191AbiKWJK4 (ORCPT ); Wed, 23 Nov 2022 04:10:56 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51526 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237215AbiKWJKl (ORCPT ); Wed, 23 Nov 2022 04:10:41 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 34C5A106130 for ; Wed, 23 Nov 2022 01:10:35 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id E1A50B81EF2 for ; Wed, 23 Nov 2022 09:10:33 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 148A6C433C1; Wed, 23 Nov 2022 09:10:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1669194632; bh=kt6BhAaOpVBl8YsCeC/iSF6b8DRYnBw9LOTo6khK7Gg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=p2yU5kB9RNbGzGz5h1nGJa9VW9hDIlh8h4fMD1cH4ZRRp89F2QmbQUFdFrqDNg9Ir bnhF6nUkIYU1e/8ZZnw6GLNkUoj9+Z+ZO684UMIqW5fd6zpj7EqUzkECy/tfUZUixl yvd0NlDl++CSVGbbr22O+vGIbzJiduWEK4Fw8jXs= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Zhengchao Shao , "David S. Miller" , Sasha Levin Subject: [PATCH 5.4 018/156] net: lapbether: fix issue of dev reference count leakage in lapbeth_device_event() Date: Wed, 23 Nov 2022 09:49:35 +0100 Message-Id: <20221123084558.558730677@linuxfoundation.org> X-Mailer: git-send-email 2.38.1 In-Reply-To: <20221123084557.816085212@linuxfoundation.org> References: <20221123084557.816085212@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Zhengchao Shao [ Upstream commit 531705a765493655472c993627106e19f7e5a6d2 ] When following tests are performed, it will cause dev reference counting leakage. a)ip link add bond2 type bond mode balance-rr b)ip link set bond2 up c)ifenslave -f bond2 rose1 d)ip link del bond2 When new bond device is created, the default type of the bond device is ether. And the bond device is up, lapbeth_device_event() receives the message and creates a new lapbeth device. In this case, the reference count value of dev is hold once. But after "ifenslave -f bond2 rose1" command is executed, the type of the bond device is changed to rose. When the bond device is unregistered, lapbeth_device_event() will not put the dev reference count. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Zhengchao Shao Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- drivers/net/wan/lapbether.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/wan/lapbether.c b/drivers/net/wan/lapbether.c index 4e42954d8cbf..bbcd8ef2873f 100644 --- a/drivers/net/wan/lapbether.c +++ b/drivers/net/wan/lapbether.c @@ -403,7 +403,7 @@ static int lapbeth_device_event(struct notifier_block *this, if (dev_net(dev) != &init_net) return NOTIFY_DONE; - if (!dev_is_ethdev(dev)) + if (!dev_is_ethdev(dev) && !lapbeth_get_x25_dev(dev)) return NOTIFY_DONE; switch (event) { -- 2.35.1