From mboxrd@z Thu Jan 1 00:00:00 1970 From: gfree.wind@foxmail.com Subject: [PATCH net v4 10/12] net: sit: Fix one possbile memleak when fail to register_netdevice Date: Tue, 2 May 2017 21:39:45 +0800 Message-ID: References: Cc: Gao Feng To: davem@davemloft.net, jiri@resnulli.us, mareklindner@neomailbox.ch, sw@simonwunderlich.de, a@unstable.cc, kuznet@ms2.inr.ac.ru, jmorris@namei.org, yoshfuji@linux-ipv6.org, kaber@trash.net, steffen.klassert@secunet.com, herbert@gondor.apana.org.au, netdev@vger.kernel.org Return-path: Received: from smtpbg65.qq.com ([103.7.28.233]:22238 "EHLO smtpbg65.qq.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750936AbdEBNkA (ORCPT ); Tue, 2 May 2017 09:40:00 -0400 In-Reply-To: Sender: netdev-owner@vger.kernel.org List-ID: From: Gao Feng The ipip6 allocates some resources in its ndo_init func, and free some of them in its destructor func. Then there is one memleak that some errors happen after register_netdevice invokes the ndo_init callback. Because only the ndo_uninit callback is invoked in the error handler of register_netdevice, but destructor not. Now create one new func ipip6_destructor_free to free the mem in the destructor, and ndo_uninit func also invokes it when fail to register the ipip6 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 --- net/ipv6/sit.c | 17 +++++++++++++---- 1 file changed, 13 insertions(+), 4 deletions(-) diff --git a/net/ipv6/sit.c b/net/ipv6/sit.c index 99853c6..28c1649 100644 --- a/net/ipv6/sit.c +++ b/net/ipv6/sit.c @@ -464,6 +464,14 @@ static void prl_list_destroy_rcu(struct rcu_head *head) return ok; } +static void ipip6_destructor_free(struct net_device *dev) +{ + struct ip_tunnel *tunnel = netdev_priv(dev); + + dst_cache_destroy(&tunnel->dst_cache); + free_percpu(dev->tstats); +} + static void ipip6_tunnel_uninit(struct net_device *dev) { struct ip_tunnel *tunnel = netdev_priv(dev); @@ -477,6 +485,10 @@ static void ipip6_tunnel_uninit(struct net_device *dev) } dst_cache_reset(&tunnel->dst_cache); dev_put(dev); + + /* dev is not registered, perform the free instead of destructor */ + if (dev->reg_state == NETREG_UNINITIALIZED) + ipip6_destructor_free(dev); } static int ipip6_err(struct sk_buff *skb, u32 info) @@ -1329,10 +1341,7 @@ static bool ipip6_valid_ip_proto(u8 ipproto) static void ipip6_dev_free(struct net_device *dev) { - struct ip_tunnel *tunnel = netdev_priv(dev); - - dst_cache_destroy(&tunnel->dst_cache); - free_percpu(dev->tstats); + ipip6_destructor_free(dev); free_netdev(dev); } -- 1.9.1