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 B9F06C4332F for ; Wed, 23 Nov 2022 08:54:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236472AbiKWIyY (ORCPT ); Wed, 23 Nov 2022 03:54:24 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57750 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236489AbiKWIyW (ORCPT ); Wed, 23 Nov 2022 03:54:22 -0500 Received: from sin.source.kernel.org (sin.source.kernel.org [IPv6:2604:1380:40e1:4800::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 31198EC7BC for ; Wed, 23 Nov 2022 00:54:21 -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 sin.source.kernel.org (Postfix) with ESMTPS id 1D67DCE20E5 for ; Wed, 23 Nov 2022 08:54:19 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id E0EC0C433D7; Wed, 23 Nov 2022 08:54:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1669193657; bh=h0DqhiKsHKlQ/FgoQm19iF6npzC7MQILPA3zQw/50p8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=lL0UHHuZ+fi2ShnnY8BOrsz+41iL5a8OxQTZaRoPcu6ErM9u/RO15D7a2G0FezNjx tpAC8cztLrSu0V1XAk7bVq1W7CLQKCOTeVOQasJVaFwbNcNpsr3X++hJRCIIgyj3g1 kibouQ6tUK9Yim8taLmppCzbUJmaJhD8S0vL8InY= 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 4.9 06/76] net: lapbether: fix issue of dev reference count leakage in lapbeth_device_event() Date: Wed, 23 Nov 2022 09:50:05 +0100 Message-Id: <20221123084546.950523956@linuxfoundation.org> X-Mailer: git-send-email 2.38.1 In-Reply-To: <20221123084546.742331901@linuxfoundation.org> References: <20221123084546.742331901@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 24daa1d0e9c5..2741bbe09ba4 100644 --- a/drivers/net/wan/lapbether.c +++ b/drivers/net/wan/lapbether.c @@ -407,7 +407,7 @@ 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