From 4b4c21fad6ae6bd58ff1566f23b0f4f70fdc9a30 Mon Sep 17 00:00:00 2001 From: Jiri Benc Date: Sun, 2 Jul 2017 19:00:58 +0200 Subject: geneve: fix hlist corruption It's not a good idea to add the same hlist_node to two different hash lists. This leads to various hard to debug memory corruptions. Fixes: 8ed66f0e8235 ("geneve: implement support for IPv6-based tunnels") Cc: John W. Linville Signed-off-by: Jiri Benc Signed-off-by: David S. Miller --- drivers/net/geneve.c | 48 ++++++++++++++++++++++++++++++++---------------- 1 file changed, 32 insertions(+), 16 deletions(-) (limited to 'drivers/net/geneve.c') diff --git a/drivers/net/geneve.c b/drivers/net/geneve.c index eb77201cb718..de8156c6b292 100644 --- a/drivers/net/geneve.c +++ b/drivers/net/geneve.c @@ -45,9 +45,17 @@ struct geneve_net { static unsigned int geneve_net_id; +struct geneve_dev_node { + struct hlist_node hlist; + struct geneve_dev *geneve; +}; + /* Pseudo network device */ struct geneve_dev { - struct hlist_node hlist; /* vni hash table */ + struct geneve_dev_node hlist4; /* vni hash table for IPv4 socket */ +#if IS_ENABLED(CONFIG_IPV6) + struct geneve_dev_node hlist6; /* vni hash table for IPv6 socket */ +#endif struct net *net; /* netns for packet i/o */ struct net_device *dev; /* netdev for geneve tunnel */ struct ip_tunnel_info info; @@ -123,16 +131,16 @@ static struct geneve_dev *geneve_lookup(struct geneve_sock *gs, __be32 addr, u8 vni[]) { struct hlist_head *vni_list_head; - struct geneve_dev *geneve; + struct geneve_dev_node *node; __u32 hash; /* Find the device for this VNI */ hash = geneve_net_vni_hash(vni); vni_list_head = &gs->vni_list[hash]; - hlist_for_each_entry_rcu(geneve, vni_list_head, hlist) { - if (eq_tun_id_and_vni((u8 *)&geneve->info.key.tun_id, vni) && - addr == geneve->info.key.u.ipv4.dst) - return geneve; + hlist_for_each_entry_rcu(node, vni_list_head, hlist) { + if (eq_tun_id_and_vni((u8 *)&node->geneve->info.key.tun_id, vni) && + addr == node->geneve->info.key.u.ipv4.dst) + return node->geneve; } return NULL; } @@ -142,16 +150,16 @@ static struct geneve_dev *geneve6_lookup(struct geneve_sock *gs, struct in6_addr addr6, u8 vni[]) { struct hlist_head *vni_list_head; - struct geneve_dev *geneve; + struct geneve_dev_node *node; __u32 hash; /* Find the device for this VNI */ hash = geneve_net_vni_hash(vni); vni_list_head = &gs->vni_list[hash]; - hlist_for_each_entry_rcu(geneve, vni_list_head, hlist) { - if (eq_tun_id_and_vni((u8 *)&geneve->info.key.tun_id, vni) && - ipv6_addr_equal(&addr6, &geneve->info.key.u.ipv6.dst)) - return geneve; + hlist_for_each_entry_rcu(node, vni_list_head, hlist) { + if (eq_tun_id_and_vni((u8 *)&node->geneve->info.key.tun_id, vni) && + ipv6_addr_equal(&addr6, &node->geneve->info.key.u.ipv6.dst)) + return node->geneve; } return NULL; } @@ -591,6 +599,7 @@ static int geneve_sock_add(struct geneve_dev *geneve, bool ipv6) { struct net *net = geneve->net; struct geneve_net *gn = net_generic(net, geneve_net_id); + struct geneve_dev_node *node; struct geneve_sock *gs; __u8 vni[3]; __u32 hash; @@ -609,15 +618,20 @@ static int geneve_sock_add(struct geneve_dev *geneve, bool ipv6) out: gs->collect_md = geneve->collect_md; #if IS_ENABLED(CONFIG_IPV6) - if (ipv6) + if (ipv6) { rcu_assign_pointer(geneve->sock6, gs); - else + node = &geneve->hlist6; + } else #endif + { rcu_assign_pointer(geneve->sock4, gs); + node = &geneve->hlist4; + } + node->geneve = geneve; tunnel_id_to_vni(geneve->info.key.tun_id, vni); hash = geneve_net_vni_hash(vni); - hlist_add_head_rcu(&geneve->hlist, &gs->vni_list[hash]); + hlist_add_head_rcu(&node->hlist, &gs->vni_list[hash]); return 0; } @@ -644,8 +658,10 @@ static int geneve_stop(struct net_device *dev) { struct geneve_dev *geneve = netdev_priv(dev); - if (!hlist_unhashed(&geneve->hlist)) - hlist_del_rcu(&geneve->hlist); + hlist_del_init_rcu(&geneve->hlist4.hlist); +#if IS_ENABLED(CONFIG_IPV6) + hlist_del_init_rcu(&geneve->hlist6.hlist); +#endif geneve_sock_release(geneve); return 0; } -- cgit v1.2.3-59-g8ed1b