From patchwork Sat Apr 29 03:48:58 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Gao Feng X-Patchwork-Id: 756641 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 3wFGwV6JbHz9s7x for ; Sat, 29 Apr 2017 13:52:26 +1000 (AEST) Authentication-Results: ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=foxmail.com header.i=@foxmail.com header.b="T3LREvYY"; dkim-atps=neutral Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1166145AbdD2DtN (ORCPT ); Fri, 28 Apr 2017 23:49:13 -0400 Received: from smtpbg302.qq.com ([184.105.206.27]:53296 "EHLO smtpbg302.qq.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1164547AbdD2DtM (ORCPT ); Fri, 28 Apr 2017 23:49:12 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=foxmail.com; s=s201512; t=1493437749; bh=oWLKNG2RWFfQudxMzsMxLG3eiTplqb+k4gWKHH6v45g=; h=From:To:Cc:Subject:Date:Message-Id; b=T3LREvYYrqePfYcZbBh12u4SPqbQ3TKPjAmW3dD2rNMw9Wanu5mp0EC9VMRbqXeJJ TTEnc5rAgCOdAo/lPlkMKx55AauTxQppSq5eVnGALkj1OQQKh4k/IqFRO+gzHl6diA 18gvC3cYVEN+jvLMMXhJ6DQaSvFeWJj//r4MGJDE= X-QQ-mid: esmtp12t1493437746tposfcbn1 Received: from localhost.localdomain (unknown [222.129.187.18]) by esmtp4.qq.com (ESMTP) with id ; Sat, 29 Apr 2017 11:48:59 +0800 (CST) X-QQ-SSF: C1000000000000F0FH600F00000000Q X-QQ-FEAT: yUqBE/5l+gd8Ll4vks7UTyKJx/r0LBNz63UblbJfweryRfD37HX3rQGJtlL7K 5zdkn7PEcBgYETJHE2c2Kea+1Ab7HZ2Q+AeL9GxL8vyba8MAILndGVbx1OXDNK2mJBSPiMz 9mTG6HIV4R5nLsRIEMNAb9z9n9a3fpI6KNx7/kEIxB+8FP+tud56wvuAl0c0QMmqlAg9UtO uAtJpKBPu6j0hmhXpxbABcRHNSBmw7nz14+V3KBz1fr0YJLPy1ZRzrggLsGAQd7dtTHHLjC elAlTSj3VYZEcljtKe2fuQUO8= X-QQ-GoodBg: 0 From: gfree.wind@foxmail.com To: davem@davemloft.net, marcelo.leitner@gmail.com, edumazet@google.com, stephen@networkplumber.org, sowmini.varadhan@oracle.com, willemb@google.com, netdev@vger.kernel.org Cc: Gao Feng Subject: [PATCH net v3] driver: loopback: Fix one possbile memleak when fail to register_netdevice Date: Sat, 29 Apr 2017 11:48:58 +0800 Message-Id: <1493437738-27028-1-git-send-email-gfree.wind@foxmail.com> X-Mailer: git-send-email 2.7.4 X-QQ-SENDSIZE: 520 X-QQ-FName: DDF7CA23880B4B4FA0BD83D9230EA852 X-QQ-LocalIP: 10.198.131.167 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Gao Feng The loopback driver allocates some resources in its ndo_init func, and free them in its destructor func. Then there is one memleak that some errors happen after register_netdevice invokes the ndo_init callback. Because the destructor would not be invoked to free the resources. Now create one new func loopback_destructor_free to free the mem in the destructor, and add ndo_uninit func also invokes it when fail to register the loopback device. It's not only free all resources, but also follow the original desgin that the resources are freed in the destructor normally after register the device successfully. Signed-off-by: Gao Feng --- v3: Split one patch to multiple commits, per David Ahern v2: Move the free in ndo_uninit when fail to register, per Herbert Xu v1: initial version drivers/net/loopback.c | 15 ++++++++++++++- 1 file changed, 14 insertions(+), 1 deletion(-) diff --git a/drivers/net/loopback.c b/drivers/net/loopback.c index b23b719..d7c1016 100644 --- a/drivers/net/loopback.c +++ b/drivers/net/loopback.c @@ -141,15 +141,28 @@ static int loopback_dev_init(struct net_device *dev) return 0; } -static void loopback_dev_free(struct net_device *dev) +static void loopback_destructor_free(struct net_device *dev) { dev_net(dev)->loopback_dev = NULL; free_percpu(dev->lstats); +} + +static void loopback_dev_uninit(struct net_device *dev) +{ + /* dev is not registered, perform the free instead of destructor */ + if (dev->reg_state == NETREG_UNINITIALIZED) + loopback_destructor_free(dev); +} + +static void loopback_dev_free(struct net_device *dev) +{ + loopback_destructor_free(dev); free_netdev(dev); } static const struct net_device_ops loopback_ops = { .ndo_init = loopback_dev_init, + .ndo_uninit = loopback_dev_uninit, .ndo_start_xmit= loopback_xmit, .ndo_get_stats64 = loopback_get_stats64, .ndo_set_mac_address = eth_mac_addr,