[PATCH net v4 06/12] net: ip6_gre: Fix one possbile memleak when fail to register_netdevice
From: <hidden>
Date: 2017-05-02 06:13:37
Subsystem:
networking [general], networking [ipv4/ipv6], the rest · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, David Ahern, Ido Schimmel, Linus Torvalds
From: Gao Feng <redacted> The ip6_gre 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 ip6_gre_destructor_free to free the mem in the destructor, and ndo_uninit func also invokes it when fail to register the ip6_gre 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 <redacted> --- net/ipv6/ip6_gre.c | 17 +++++++++++++---- 1 file changed, 13 insertions(+), 4 deletions(-)
diff --git a/net/ipv6/ip6_gre.c b/net/ipv6/ip6_gre.c
index 6fcb7cb..e53c3ac 100644
--- a/net/ipv6/ip6_gre.c
+++ b/net/ipv6/ip6_gre.c@@ -355,6 +355,14 @@ static struct ip6_tnl *ip6gre_tunnel_locate(struct net *net, return NULL; } +static void ip6gre_destructor_free(struct net_device *dev) +{ + struct ip6_tnl *t = netdev_priv(dev); + + dst_cache_destroy(&t->dst_cache); + free_percpu(dev->tstats); +} + static void ip6gre_tunnel_uninit(struct net_device *dev) { struct ip6_tnl *t = netdev_priv(dev);
@@ -363,6 +371,10 @@ static void ip6gre_tunnel_uninit(struct net_device *dev) ip6gre_tunnel_unlink(ign, t); dst_cache_reset(&t->dst_cache); dev_put(dev); + + /* dev is not registered, perform the free instead of destructor */ + if (dev->reg_state == NETREG_UNINITIALIZED) + ip6gre_destructor_free(dev); }
@@ -981,10 +993,7 @@ static int ip6gre_header(struct sk_buff *skb, struct net_device *dev, static void ip6gre_dev_free(struct net_device *dev) { - struct ip6_tnl *t = netdev_priv(dev); - - dst_cache_destroy(&t->dst_cache); - free_percpu(dev->tstats); + ip6gre_destructor_free(dev); free_netdev(dev); }
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1.9.1