diff options
Diffstat (limited to 'net/l2tp')
-rw-r--r-- | net/l2tp/l2tp_core.c | 178 | ||||
-rw-r--r-- | net/l2tp/l2tp_core.h | 17 | ||||
-rw-r--r-- | net/l2tp/l2tp_debugfs.c | 10 | ||||
-rw-r--r-- | net/l2tp/l2tp_eth.c | 86 | ||||
-rw-r--r-- | net/l2tp/l2tp_ip.c | 22 | ||||
-rw-r--r-- | net/l2tp/l2tp_ip6.c | 23 | ||||
-rw-r--r-- | net/l2tp/l2tp_netlink.c | 57 | ||||
-rw-r--r-- | net/l2tp/l2tp_ppp.c | 103 |
8 files changed, 318 insertions, 178 deletions
diff --git a/net/l2tp/l2tp_core.c b/net/l2tp/l2tp_core.c index 8adab6335ced..fa0342574b89 100644 --- a/net/l2tp/l2tp_core.c +++ b/net/l2tp/l2tp_core.c @@ -120,7 +120,7 @@ static inline struct l2tp_tunnel *l2tp_tunnel(struct sock *sk) return sk->sk_user_data; } -static inline struct l2tp_net *l2tp_pernet(struct net *net) +static inline struct l2tp_net *l2tp_pernet(const struct net *net) { BUG_ON(!net); @@ -217,27 +217,6 @@ static void l2tp_tunnel_sock_put(struct sock *sk) sock_put(sk); } -/* Lookup a session by id in the global session list - */ -static struct l2tp_session *l2tp_session_find_2(struct net *net, u32 session_id) -{ - struct l2tp_net *pn = l2tp_pernet(net); - struct hlist_head *session_list = - l2tp_session_id_hash_2(pn, session_id); - struct l2tp_session *session; - - rcu_read_lock_bh(); - hlist_for_each_entry_rcu(session, session_list, global_hlist) { - if (session->session_id == session_id) { - rcu_read_unlock_bh(); - return session; - } - } - rcu_read_unlock_bh(); - - return NULL; -} - /* Session hash list. * The session_id SHOULD be random according to RFC2661, but several * L2TP implementations (Cisco and Microsoft) use incrementing @@ -250,25 +229,46 @@ l2tp_session_id_hash(struct l2tp_tunnel *tunnel, u32 session_id) return &tunnel->session_hlist[hash_32(session_id, L2TP_HASH_BITS)]; } -/* Lookup a session by id +/* Lookup a session. A new reference is held on the returned session. + * Optionally calls session->ref() too if do_ref is true. */ -struct l2tp_session *l2tp_session_find(struct net *net, struct l2tp_tunnel *tunnel, u32 session_id) +struct l2tp_session *l2tp_session_get(const struct net *net, + struct l2tp_tunnel *tunnel, + u32 session_id, bool do_ref) { struct hlist_head *session_list; struct l2tp_session *session; - /* In L2TPv3, session_ids are unique over all tunnels and we - * sometimes need to look them up before we know the - * tunnel. - */ - if (tunnel == NULL) - return l2tp_session_find_2(net, session_id); + if (!tunnel) { + struct l2tp_net *pn = l2tp_pernet(net); + + session_list = l2tp_session_id_hash_2(pn, session_id); + + rcu_read_lock_bh(); + hlist_for_each_entry_rcu(session, session_list, global_hlist) { + if (session->session_id == session_id) { + l2tp_session_inc_refcount(session); + if (do_ref && session->ref) + session->ref(session); + rcu_read_unlock_bh(); + + return session; + } + } + rcu_read_unlock_bh(); + + return NULL; + } session_list = l2tp_session_id_hash(tunnel, session_id); read_lock_bh(&tunnel->hlist_lock); hlist_for_each_entry(session, session_list, hlist) { if (session->session_id == session_id) { + l2tp_session_inc_refcount(session); + if (do_ref && session->ref) + session->ref(session); read_unlock_bh(&tunnel->hlist_lock); + return session; } } @@ -276,9 +276,10 @@ struct l2tp_session *l2tp_session_find(struct net *net, struct l2tp_tunnel *tunn return NULL; } -EXPORT_SYMBOL_GPL(l2tp_session_find); +EXPORT_SYMBOL_GPL(l2tp_session_get); -struct l2tp_session *l2tp_session_find_nth(struct l2tp_tunnel *tunnel, int nth) +struct l2tp_session *l2tp_session_get_nth(struct l2tp_tunnel *tunnel, int nth, + bool do_ref) { int hash; struct l2tp_session *session; @@ -288,6 +289,9 @@ struct l2tp_session *l2tp_session_find_nth(struct l2tp_tunnel *tunnel, int nth) for (hash = 0; hash < L2TP_HASH_SIZE; hash++) { hlist_for_each_entry(session, &tunnel->session_hlist[hash], hlist) { if (++count > nth) { + l2tp_session_inc_refcount(session); + if (do_ref && session->ref) + session->ref(session); read_unlock_bh(&tunnel->hlist_lock); return session; } @@ -298,12 +302,14 @@ struct l2tp_session *l2tp_session_find_nth(struct l2tp_tunnel *tunnel, int nth) return NULL; } -EXPORT_SYMBOL_GPL(l2tp_session_find_nth); +EXPORT_SYMBOL_GPL(l2tp_session_get_nth); /* Lookup a session by interface name. * This is very inefficient but is only used by management interfaces. */ -struct l2tp_session *l2tp_session_find_by_ifname(struct net *net, char *ifname) +struct l2tp_session *l2tp_session_get_by_ifname(const struct net *net, + const char *ifname, + bool do_ref) { struct l2tp_net *pn = l2tp_pernet(net); int hash; @@ -313,7 +319,11 @@ struct l2tp_session *l2tp_session_find_by_ifname(struct net *net, char *ifname) for (hash = 0; hash < L2TP_HASH_SIZE_2; hash++) { hlist_for_each_entry_rcu(session, &pn->l2tp_session_hlist[hash], global_hlist) { if (!strcmp(session->ifname, ifname)) { + l2tp_session_inc_refcount(session); + if (do_ref && session->ref) + session->ref(session); rcu_read_unlock_bh(); + return session; } } @@ -323,11 +333,53 @@ struct l2tp_session *l2tp_session_find_by_ifname(struct net *net, char *ifname) return NULL; } -EXPORT_SYMBOL_GPL(l2tp_session_find_by_ifname); +EXPORT_SYMBOL_GPL(l2tp_session_get_by_ifname); + +static int l2tp_session_add_to_tunnel(struct l2tp_tunnel *tunnel, + struct l2tp_session *session) +{ + struct l2tp_session *session_walk; + struct hlist_head *g_head; + struct hlist_head *head; + struct l2tp_net *pn; + + head = l2tp_session_id_hash(tunnel, session->session_id); + + write_lock_bh(&tunnel->hlist_lock); + hlist_for_each_entry(session_walk, head, hlist) + if (session_walk->session_id == session->session_id) + goto exist; + + if (tunnel->version == L2TP_HDR_VER_3) { + pn = l2tp_pernet(tunnel->l2tp_net); + g_head = l2tp_session_id_hash_2(l2tp_pernet(tunnel->l2tp_net), + session->session_id); + + spin_lock_bh(&pn->l2tp_session_hlist_lock); + hlist_for_each_entry(session_walk, g_head, global_hlist) + if (session_walk->session_id == session->session_id) + goto exist_glob; + + hlist_add_head_rcu(&session->global_hlist, g_head); + spin_unlock_bh(&pn->l2tp_session_hlist_lock); + } + + hlist_add_head(&session->hlist, head); + write_unlock_bh(&tunnel->hlist_lock); + + return 0; + +exist_glob: + spin_unlock_bh(&pn->l2tp_session_hlist_lock); +exist: + write_unlock_bh(&tunnel->hlist_lock); + + return -EEXIST; +} /* Lookup a tunnel by id */ -struct l2tp_tunnel *l2tp_tunnel_find(struct net *net, u32 tunnel_id) +struct l2tp_tunnel *l2tp_tunnel_find(const struct net *net, u32 tunnel_id) { struct l2tp_tunnel *tunnel; struct l2tp_net *pn = l2tp_pernet(net); @@ -345,7 +397,7 @@ struct l2tp_tunnel *l2tp_tunnel_find(struct net *net, u32 tunnel_id) } EXPORT_SYMBOL_GPL(l2tp_tunnel_find); -struct l2tp_tunnel *l2tp_tunnel_find_nth(struct net *net, int nth) +struct l2tp_tunnel *l2tp_tunnel_find_nth(const struct net *net, int nth) { struct l2tp_net *pn = l2tp_pernet(net); struct l2tp_tunnel *tunnel; @@ -633,6 +685,9 @@ discard: * a data (not control) frame before coming here. Fields up to the * session-id have already been parsed and ptr points to the data * after the session-id. + * + * session->ref() must have been called prior to l2tp_recv_common(). + * session->deref() will be called automatically after skb is processed. */ void l2tp_recv_common(struct l2tp_session *session, struct sk_buff *skb, unsigned char *ptr, unsigned char *optr, u16 hdrflags, @@ -642,14 +697,6 @@ void l2tp_recv_common(struct l2tp_session *session, struct sk_buff *skb, int offset; u32 ns, nr; - /* The ref count is increased since we now hold a pointer to - * the session. Take care to decrement the refcnt when exiting - * this function from now on... - */ - l2tp_session_inc_refcount(session); - if (session->ref) - (*session->ref)(session); - /* Parse and check optional cookie */ if (session->peer_cookie_len > 0) { if (memcmp(ptr, &session->peer_cookie[0], session->peer_cookie_len)) { @@ -802,8 +849,6 @@ void l2tp_recv_common(struct l2tp_session *session, struct sk_buff *skb, /* Try to dequeue as many skbs from reorder_q as we can. */ l2tp_recv_dequeue(session); - l2tp_session_dec_refcount(session); - return; discard: @@ -812,8 +857,6 @@ discard: if (session->deref) (*session->deref)(session); - - l2tp_session_dec_refcount(session); } EXPORT_SYMBOL(l2tp_recv_common); @@ -920,8 +963,14 @@ static int l2tp_udp_recv_core(struct l2tp_tunnel *tunnel, struct sk_buff *skb, } /* Find the session context */ - session = l2tp_session_find(tunnel->l2tp_net, tunnel, session_id); + session = l2tp_session_get(tunnel->l2tp_net, tunnel, session_id, true); if (!session || !session->recv_skb) { + if (session) { + if (session->deref) + session->deref(session); + l2tp_session_dec_refcount(session); + } + /* Not found? Pass to userspace to deal with */ l2tp_info(tunnel, L2TP_MSG_DATA, "%s: no session found (%u/%u). Passing up.\n", @@ -930,6 +979,7 @@ static int l2tp_udp_recv_core(struct l2tp_tunnel *tunnel, struct sk_buff *skb, } l2tp_recv_common(session, skb, ptr, optr, hdrflags, length, payload_hook); + l2tp_session_dec_refcount(session); return 0; @@ -1738,6 +1788,7 @@ EXPORT_SYMBOL_GPL(l2tp_session_set_header_len); struct l2tp_session *l2tp_session_create(int priv_size, struct l2tp_tunnel *tunnel, u32 session_id, u32 peer_session_id, struct l2tp_session_cfg *cfg) { struct l2tp_session *session; + int err; session = kzalloc(sizeof(struct l2tp_session) + priv_size, GFP_KERNEL); if (session != NULL) { @@ -1793,6 +1844,13 @@ struct l2tp_session *l2tp_session_create(int priv_size, struct l2tp_tunnel *tunn l2tp_session_set_header_len(session, tunnel->version); + err = l2tp_session_add_to_tunnel(tunnel, session); + if (err) { + kfree(session); + + return ERR_PTR(err); + } + /* Bump the reference count. The session context is deleted * only when this drops to zero. */ @@ -1802,28 +1860,14 @@ struct l2tp_session *l2tp_session_create(int priv_size, struct l2tp_tunnel *tunn /* Ensure tunnel socket isn't deleted */ sock_hold(tunnel->sock); - /* Add session to the tunnel's hash list */ - write_lock_bh(&tunnel->hlist_lock); - hlist_add_head(&session->hlist, - l2tp_session_id_hash(tunnel, session_id)); - write_unlock_bh(&tunnel->hlist_lock); - - /* And to the global session list if L2TPv3 */ - if (tunnel->version != L2TP_HDR_VER_2) { - struct l2tp_net *pn = l2tp_pernet(tunnel->l2tp_net); - - spin_lock_bh(&pn->l2tp_session_hlist_lock); - hlist_add_head_rcu(&session->global_hlist, - l2tp_session_id_hash_2(pn, session_id)); - spin_unlock_bh(&pn->l2tp_session_hlist_lock); - } - /* Ignore management session in session count value */ if (session->session_id != 0) atomic_inc(&l2tp_session_count); + + return session; } - return session; + return ERR_PTR(-ENOMEM); } EXPORT_SYMBOL_GPL(l2tp_session_create); diff --git a/net/l2tp/l2tp_core.h b/net/l2tp/l2tp_core.h index aebf281d09ee..eec5ad2ebb93 100644 --- a/net/l2tp/l2tp_core.h +++ b/net/l2tp/l2tp_core.h @@ -230,13 +230,16 @@ out: return tunnel; } -struct l2tp_session *l2tp_session_find(struct net *net, - struct l2tp_tunnel *tunnel, - u32 session_id); -struct l2tp_session *l2tp_session_find_nth(struct l2tp_tunnel *tunnel, int nth); -struct l2tp_session *l2tp_session_find_by_ifname(struct net *net, char *ifname); -struct l2tp_tunnel *l2tp_tunnel_find(struct net *net, u32 tunnel_id); -struct l2tp_tunnel *l2tp_tunnel_find_nth(struct net *net, int nth); +struct l2tp_session *l2tp_session_get(const struct net *net, + struct l2tp_tunnel *tunnel, + u32 session_id, bool do_ref); +struct l2tp_session *l2tp_session_get_nth(struct l2tp_tunnel *tunnel, int nth, + bool do_ref); +struct l2tp_session *l2tp_session_get_by_ifname(const struct net *net, + const char *ifname, + bool do_ref); +struct l2tp_tunnel *l2tp_tunnel_find(const struct net *net, u32 tunnel_id); +struct l2tp_tunnel *l2tp_tunnel_find_nth(const struct net *net, int nth); int l2tp_tunnel_create(struct net *net, int fd, int version, u32 tunnel_id, u32 peer_tunnel_id, struct l2tp_tunnel_cfg *cfg, diff --git a/net/l2tp/l2tp_debugfs.c b/net/l2tp/l2tp_debugfs.c index 2d6760a2ae34..d100aed3d06f 100644 --- a/net/l2tp/l2tp_debugfs.c +++ b/net/l2tp/l2tp_debugfs.c @@ -53,7 +53,7 @@ static void l2tp_dfs_next_tunnel(struct l2tp_dfs_seq_data *pd) static void l2tp_dfs_next_session(struct l2tp_dfs_seq_data *pd) { - pd->session = l2tp_session_find_nth(pd->tunnel, pd->session_idx); + pd->session = l2tp_session_get_nth(pd->tunnel, pd->session_idx, true); pd->session_idx++; if (pd->session == NULL) { @@ -238,10 +238,14 @@ static int l2tp_dfs_seq_show(struct seq_file *m, void *v) } /* Show the tunnel or session context */ - if (pd->session == NULL) + if (!pd->session) { l2tp_dfs_seq_tunnel_show(m, pd->tunnel); - else + } else { l2tp_dfs_seq_session_show(m, pd->session); + if (pd->session->deref) + pd->session->deref(pd->session); + l2tp_session_dec_refcount(pd->session); + } out: return 0; diff --git a/net/l2tp/l2tp_eth.c b/net/l2tp/l2tp_eth.c index 8bf18a5f66e0..8b21af7321b9 100644 --- a/net/l2tp/l2tp_eth.c +++ b/net/l2tp/l2tp_eth.c @@ -30,6 +30,9 @@ #include <net/xfrm.h> #include <net/net_namespace.h> #include <net/netns/generic.h> +#include <linux/ip.h> +#include <linux/ipv6.h> +#include <linux/udp.h> #include "l2tp_core.h" @@ -127,8 +130,13 @@ static const struct net_device_ops l2tp_eth_netdev_ops = { .ndo_set_mac_address = eth_mac_addr, }; +static struct device_type l2tpeth_type = { + .name = "l2tpeth", +}; + static void l2tp_eth_dev_setup(struct net_device *dev) { + SET_NETDEV_DEVTYPE(dev, &l2tpeth_type); ether_setup(dev); dev->priv_flags &= ~IFF_TX_SKB_SHARING; dev->features |= NETIF_F_LLTX; @@ -204,8 +212,58 @@ static void l2tp_eth_show(struct seq_file *m, void *arg) } #endif +static void l2tp_eth_adjust_mtu(struct l2tp_tunnel *tunnel, + struct l2tp_session *session, + struct net_device *dev) +{ + unsigned int overhead = 0; + struct dst_entry *dst; + u32 l3_overhead = 0; + + /* if the encap is UDP, account for UDP header size */ + if (tunnel->encap == L2TP_ENCAPTYPE_UDP) { + overhead += sizeof(struct udphdr); + dev->needed_headroom += sizeof(struct udphdr); + } + if (session->mtu != 0) { + dev->mtu = session->mtu; + dev->needed_headroom += session->hdr_len; + return; + } + lock_sock(tunnel->sock); + l3_overhead = kernel_sock_ip_overhead(tunnel->sock); + release_sock(tunnel->sock); + if (l3_overhead == 0) { + /* L3 Overhead couldn't be identified, this could be + * because tunnel->sock was NULL or the socket's + * address family was not IPv4 or IPv6, + * dev mtu stays at 1500. + */ + return; + } + /* Adjust MTU, factor overhead - underlay L3, overlay L2 hdr + * UDP overhead, if any, was already factored in above. + */ + overhead += session->hdr_len + ETH_HLEN + l3_overhead; + + /* If PMTU discovery was enabled, use discovered MTU on L2TP device */ + dst = sk_dst_get(tunnel->sock); + if (dst) { + /* dst_mtu will use PMTU if found, else fallback to intf MTU */ + u32 pmtu = dst_mtu(dst); + + if (pmtu != 0) + dev->mtu = pmtu; + dst_release(dst); + } + session->mtu = dev->mtu - overhead; + dev->mtu = session->mtu; + dev->needed_headroom += session->hdr_len; +} + static int l2tp_eth_create(struct net *net, u32 tunnel_id, u32 session_id, u32 peer_session_id, struct l2tp_session_cfg *cfg) { + unsigned char name_assign_type; struct net_device *dev; char name[IFNAMSIZ]; struct l2tp_tunnel *tunnel; @@ -221,31 +279,22 @@ static int l2tp_eth_create(struct net *net, u32 tunnel_id, u32 session_id, u32 p goto out; } - session = l2tp_session_find(net, tunnel, session_id); - if (session) { - rc = -EEXIST; - goto out; - } - if (cfg->ifname) { - dev = dev_get_by_name(net, cfg->ifname); - if (dev) { - dev_put(dev); - rc = -EEXIST; - goto out; - } strlcpy(name, cfg->ifname, IFNAMSIZ); - } else + name_assign_type = NET_NAME_USER; + } else { strcpy(name, L2TP_ETH_DEV_NAME); + name_assign_type = NET_NAME_ENUM; + } session = l2tp_session_create(sizeof(*spriv), tunnel, session_id, peer_session_id, cfg); - if (!session) { - rc = -ENOMEM; + if (IS_ERR(session)) { + rc = PTR_ERR(session); goto out; } - dev = alloc_netdev(sizeof(*priv), name, NET_NAME_UNKNOWN, + dev = alloc_netdev(sizeof(*priv), name, name_assign_type, l2tp_eth_dev_setup); if (!dev) { rc = -ENOMEM; @@ -253,12 +302,9 @@ static int l2tp_eth_create(struct net *net, u32 tunnel_id, u32 session_id, u32 p } dev_net_set(dev, net); - if (session->mtu == 0) - session->mtu = dev->mtu - session->hdr_len; - dev->mtu = session->mtu; - dev->needed_headroom += session->hdr_len; dev->min_mtu = 0; dev->max_mtu = ETH_MAX_MTU; + l2tp_eth_adjust_mtu(tunnel, session, dev); priv = netdev_priv(dev); priv->dev = dev; diff --git a/net/l2tp/l2tp_ip.c b/net/l2tp/l2tp_ip.c index d25038cfd64e..4d322c1b7233 100644 --- a/net/l2tp/l2tp_ip.c +++ b/net/l2tp/l2tp_ip.c @@ -143,19 +143,19 @@ static int l2tp_ip_recv(struct sk_buff *skb) } /* Ok, this is a data packet. Lookup the session. */ - session = l2tp_session_find(net, NULL, session_id); - if (session == NULL) + session = l2tp_session_get(net, NULL, session_id, true); + if (!session) goto discard; tunnel = session->tunnel; - if (tunnel == NULL) - goto discard; + if (!tunnel) + goto discard_sess; /* Trace packet contents, if enabled */ if (tunnel->debug & L2TP_MSG_DATA) { length = min(32u, skb->len); if (!pskb_may_pull(skb, length)) - goto discard; + goto discard_sess; /* Point to L2TP header */ optr = ptr = skb->data; @@ -165,6 +165,7 @@ static int l2tp_ip_recv(struct sk_buff *skb) } l2tp_recv_common(session, skb, ptr, optr, 0, skb->len, tunnel->recv_payload_hook); + l2tp_session_dec_refcount(session); return 0; @@ -178,9 +179,10 @@ pass_up: tunnel_id = ntohl(*(__be32 *) &skb->data[4]); tunnel = l2tp_tunnel_find(net, tunnel_id); - if (tunnel != NULL) + if (tunnel) { sk = tunnel->sock; - else { + sock_hold(sk); + } else { struct iphdr *iph = (struct iphdr *) skb_network_header(skb); read_lock_bh(&l2tp_ip_lock); @@ -202,6 +204,12 @@ pass_up: return sk_receive_skb(sk, skb, 1); +discard_sess: + if (session->deref) + session->deref(session); + l2tp_session_dec_refcount(session); + goto discard; + discard_put: sock_put(sk); diff --git a/net/l2tp/l2tp_ip6.c b/net/l2tp/l2tp_ip6.c index a4abcbc4c09a..88b397c30d86 100644 --- a/net/l2tp/l2tp_ip6.c +++ b/net/l2tp/l2tp_ip6.c @@ -156,19 +156,19 @@ static int l2tp_ip6_recv(struct sk_buff *skb) } /* Ok, this is a data packet. Lookup the session. */ - session = l2tp_session_find(net, NULL, session_id); - if (session == NULL) + session = l2tp_session_get(net, NULL, session_id, true); + if (!session) goto discard; tunnel = session->tunnel; - if (tunnel == NULL) - goto discard; + if (!tunnel) + goto discard_sess; /* Trace packet contents, if enabled */ if (tunnel->debug & L2TP_MSG_DATA) { length = min(32u, skb->len); if (!pskb_may_pull(skb, length)) - goto discard; + goto discard_sess; /* Point to L2TP header */ optr = ptr = skb->data; @@ -179,6 +179,8 @@ static int l2tp_ip6_recv(struct sk_buff *skb) l2tp_recv_common(session, skb, ptr, optr, 0, skb->len, tunnel->recv_payload_hook); + l2tp_session_dec_refcount(session); + return 0; pass_up: @@ -191,9 +193,10 @@ pass_up: tunnel_id = ntohl(*(__be32 *) &skb->data[4]); tunnel = l2tp_tunnel_find(net, tunnel_id); - if (tunnel != NULL) + if (tunnel) { sk = tunnel->sock; - else { + sock_hold(sk); + } else { struct ipv6hdr *iph = ipv6_hdr(skb); read_lock_bh(&l2tp_ip6_lock); @@ -215,6 +218,12 @@ pass_up: return sk_receive_skb(sk, skb, 1); +discard_sess: + if (session->deref) + session->deref(session); + l2tp_session_dec_refcount(session); + goto discard; + discard_put: sock_put(sk); diff --git a/net/l2tp/l2tp_netlink.c b/net/l2tp/l2tp_netlink.c index 3620fba31786..12cfcd0ca807 100644 --- a/net/l2tp/l2tp_netlink.c +++ b/net/l2tp/l2tp_netlink.c @@ -48,7 +48,8 @@ static int l2tp_nl_session_send(struct sk_buff *skb, u32 portid, u32 seq, /* Accessed under genl lock */ static const struct l2tp_nl_cmd_ops *l2tp_nl_cmd_ops[__L2TP_PWTYPE_MAX]; -static struct l2tp_session *l2tp_nl_session_find(struct genl_info *info) +static struct l2tp_session *l2tp_nl_session_get(struct genl_info *info, + bool do_ref) { u32 tunnel_id; u32 session_id; @@ -59,14 +60,15 @@ static struct l2tp_session *l2tp_nl_session_find(struct genl_info *info) if (info->attrs[L2TP_ATTR_IFNAME]) { ifname = nla_data(info->attrs[L2TP_ATTR_IFNAME]); - session = l2tp_session_find_by_ifname(net, ifname); + session = l2tp_session_get_by_ifname(net, ifname, do_ref); } else if ((info->attrs[L2TP_ATTR_SESSION_ID]) && (info->attrs[L2TP_ATTR_CONN_ID])) { tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_CONN_ID]); session_id = nla_get_u32(info->attrs[L2TP_ATTR_SESSION_ID]); tunnel = l2tp_tunnel_find(net, tunnel_id); if (tunnel) - session = l2tp_session_find(net, tunnel, session_id); + session = l2tp_session_get(net, tunnel, session_id, + do_ref); } return session; @@ -519,11 +521,6 @@ static int l2tp_nl_cmd_session_create(struct sk_buff *skb, struct genl_info *inf goto out; } session_id = nla_get_u32(info->attrs[L2TP_ATTR_SESSION_ID]); - session = l2tp_session_find(net, tunnel, session_id); - if (session) { - ret = -EEXIST; - goto out; - } if (!info->attrs[L2TP_ATTR_PEER_SESSION_ID]) { ret = -EINVAL; @@ -642,10 +639,12 @@ static int l2tp_nl_cmd_session_create(struct sk_buff *skb, struct genl_info *inf session_id, peer_session_id, &cfg); if (ret >= 0) { - session = l2tp_session_find(net, tunnel, session_id); - if (session) + session = l2tp_session_get(net, tunnel, session_id, false); + if (session) { ret = l2tp_session_notify(&l2tp_nl_family, info, session, L2TP_CMD_SESSION_CREATE); + l2tp_session_dec_refcount(session); + } } out: @@ -658,7 +657,7 @@ static int l2tp_nl_cmd_session_delete(struct sk_buff *skb, struct genl_info *inf struct l2tp_session *session; u16 pw_type; - session = l2tp_nl_session_find(info); + session = l2tp_nl_session_get(info, true); if (session == NULL) { ret = -ENODEV; goto out; @@ -672,6 +671,10 @@ static int l2tp_nl_cmd_session_delete(struct sk_buff *skb, struct genl_info *inf if (l2tp_nl_cmd_ops[pw_type] && l2tp_nl_cmd_ops[pw_type]->session_delete) ret = (*l2tp_nl_cmd_ops[pw_type]->session_delete)(session); + if (session->deref) + session->deref(session); + l2tp_session_dec_refcount(session); + out: return ret; } @@ -681,7 +684,7 @@ static int l2tp_nl_cmd_session_modify(struct sk_buff *skb, struct genl_info *inf int ret = 0; struct l2tp_session *session; - session = l2tp_nl_session_find(info); + session = l2tp_nl_session_get(info, false); if (session == NULL) { ret = -ENODEV; goto out; @@ -716,6 +719,8 @@ static int l2tp_nl_cmd_session_modify(struct sk_buff *skb, struct genl_info *inf ret = l2tp_session_notify(&l2tp_nl_family, info, session, L2TP_CMD_SESSION_MODIFY); + l2tp_session_dec_refcount(session); + out: return ret; } @@ -811,29 +816,34 @@ static int l2tp_nl_cmd_session_get(struct sk_buff *skb, struct genl_info *info) struct sk_buff *msg; int ret; - session = l2tp_nl_session_find(info); + session = l2tp_nl_session_get(info, false); if (session == NULL) { ret = -ENODEV; - goto out; + goto err; } msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); if (!msg) { ret = -ENOMEM; - goto out; + goto err_ref; } ret = l2tp_nl_session_send(msg, info->snd_portid, info->snd_seq, 0, session, L2TP_CMD_SESSION_GET); if (ret < 0) - goto err_out; + goto err_ref_msg; - return genlmsg_unicast(genl_info_net(info), msg, info->snd_portid); + ret = genlmsg_unicast(genl_info_net(info), msg, info->snd_portid); -err_out: - nlmsg_free(msg); + l2tp_session_dec_refcount(session); -out: + return ret; + +err_ref_msg: + nlmsg_free(msg); +err_ref: + l2tp_session_dec_refcount(session); +err: return ret; } @@ -852,7 +862,7 @@ static int l2tp_nl_cmd_session_dump(struct sk_buff *skb, struct netlink_callback goto out; } - session = l2tp_session_find_nth(tunnel, si); + session = l2tp_session_get_nth(tunnel, si, false); if (session == NULL) { ti++; tunnel = NULL; @@ -862,8 +872,11 @@ static int l2tp_nl_cmd_session_dump(struct sk_buff *skb, struct netlink_callback if (l2tp_nl_session_send(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq, NLM_F_MULTI, - session, L2TP_CMD_SESSION_GET) < 0) + session, L2TP_CMD_SESSION_GET) < 0) { + l2tp_session_dec_refcount(session); break; + } + l2tp_session_dec_refcount(session); si++; } diff --git a/net/l2tp/l2tp_ppp.c b/net/l2tp/l2tp_ppp.c index 36cc56fd0418..32ea0f3d868c 100644 --- a/net/l2tp/l2tp_ppp.c +++ b/net/l2tp/l2tp_ppp.c @@ -450,6 +450,10 @@ static void pppol2tp_session_close(struct l2tp_session *session) static void pppol2tp_session_destruct(struct sock *sk) { struct l2tp_session *session = sk->sk_user_data; + + skb_queue_purge(&sk->sk_receive_queue); + skb_queue_purge(&sk->sk_write_queue); + if (session) { sk->sk_user_data = NULL; BUG_ON(session->magic != L2TP_SESSION_MAGIC); @@ -488,9 +492,6 @@ static int pppol2tp_release(struct socket *sock) l2tp_session_queue_purge(session); sock_put(sk); } - skb_queue_purge(&sk->sk_receive_queue); - skb_queue_purge(&sk->sk_write_queue); - release_sock(sk); /* This will delete the session context via @@ -582,6 +583,7 @@ static int pppol2tp_connect(struct socket *sock, struct sockaddr *uservaddr, int error = 0; u32 tunnel_id, peer_tunnel_id; u32 session_id, peer_session_id; + bool drop_refcnt = false; int ver = 2; int fd; @@ -683,36 +685,36 @@ static int pppol2tp_connect(struct socket *sock, struct sockaddr *uservaddr, if (tunnel->peer_tunnel_id == 0) tunnel->peer_tunnel_id = peer_tunnel_id; - /* Create session if it doesn't already exist. We handle the - * case where a session was previously created by the netlink - * interface by checking that the session doesn't already have - * a socket and its tunnel socket are what we expect. If any - * of those checks fail, return EEXIST to the caller. - */ - session = l2tp_session_find(sock_net(sk), tunnel, session_id); - if (session == NULL) { - /* Default MTU must allow space for UDP/L2TP/PPP - * headers. + session = l2tp_session_get(sock_net(sk), tunnel, session_id, false); + if (session) { + drop_refcnt = true; + ps = l2tp_session_priv(session); + + /* Using a pre-existing session is fine as long as it hasn't + * been connected yet. */ - cfg.mtu = cfg.mru = 1500 - PPPOL2TP_HEADER_OVERHEAD; + if (ps->sock) { + error = -EEXIST; + goto end; + } - /* Allocate and initialize a new session context. */ - session = l2tp_session_create(sizeof(struct pppol2tp_session), - tunnel, session_id, - peer_session_id, &cfg); - if (session == NULL) { - error = -ENOMEM; + /* consistency checks */ + if (ps->tunnel_sock != tunnel->sock) { + error = -EEXIST; goto end; } } else { - ps = l2tp_session_priv(session); - error = -EEXIST; - if (ps->sock != NULL) - goto end; + /* Default MTU must allow space for UDP/L2TP/PPP headers */ + cfg.mtu = 1500 - PPPOL2TP_HEADER_OVERHEAD; + cfg.mru = cfg.mtu; - /* consistency checks */ - if (ps->tunnel_sock != tunnel->sock) + session = l2tp_session_create(sizeof(struct pppol2tp_session), + tunnel, session_id, + peer_session_id, &cfg); + if (IS_ERR(session)) { + error = PTR_ERR(session); goto end; + } } /* Associate session with its PPPoL2TP socket */ @@ -777,6 +779,8 @@ out_no_ppp: session->name); end: + if (drop_refcnt) + l2tp_session_dec_refcount(session); release_sock(sk); return error; @@ -804,12 +808,6 @@ static int pppol2tp_session_create(struct net *net, u32 tunnel_id, u32 session_i if (tunnel->sock == NULL) goto out; - /* Check that this session doesn't already exist */ - error = -EEXIST; - session = l2tp_session_find(net, tunnel, session_id); - if (session != NULL) - goto out; - /* Default MTU values. */ if (cfg->mtu == 0) cfg->mtu = 1500 - PPPOL2TP_HEADER_OVERHEAD; @@ -817,12 +815,13 @@ static int pppol2tp_session_create(struct net *net, u32 tunnel_id, u32 session_i cfg->mru = cfg->mtu; /* Allocate and initialize a new session context. */ - error = -ENOMEM; session = l2tp_session_create(sizeof(struct pppol2tp_session), tunnel, session_id, peer_session_id, cfg); - if (session == NULL) + if (IS_ERR(session)) { + error = PTR_ERR(session); goto out; + } ps = l2tp_session_priv(session); ps->tunnel_sock = tunnel->sock; @@ -1140,11 +1139,18 @@ static int pppol2tp_tunnel_ioctl(struct l2tp_tunnel *tunnel, if (stats.session_id != 0) { /* resend to session ioctl handler */ struct l2tp_session *session = - l2tp_session_find(sock_net(sk), tunnel, stats.session_id); - if (session != NULL) - err = pppol2tp_session_ioctl(session, cmd, arg); - else + l2tp_session_get(sock_net(sk), tunnel, + stats.session_id, true); + + if (session) { + err = pppol2tp_session_ioctl(session, cmd, + arg); + if (session->deref) + session->deref(session); + l2tp_session_dec_refcount(session); + } else { err = -EBADR; + } break; } #ifdef CONFIG_XFRM @@ -1377,8 +1383,6 @@ static int pppol2tp_setsockopt(struct socket *sock, int level, int optname, } else err = pppol2tp_session_setsockopt(sk, session, optname, val); - err = 0; - end_put_sess: sock_put(sk); end: @@ -1501,8 +1505,13 @@ static int pppol2tp_getsockopt(struct socket *sock, int level, int optname, err = pppol2tp_tunnel_getsockopt(sk, tunnel, optname, &val); sock_put(ps->tunnel_sock); - } else + if (err) + goto end_put_sess; + } else { err = pppol2tp_session_getsockopt(sk, session, optname, &val); + if (err) + goto end_put_sess; + } err = -EFAULT; if (put_user(len, optlen)) @@ -1554,7 +1563,7 @@ static void pppol2tp_next_tunnel(struct net *net, struct pppol2tp_seq_data *pd) static void pppol2tp_next_session(struct net *net, struct pppol2tp_seq_data *pd) { - pd->session = l2tp_session_find_nth(pd->tunnel, pd->session_idx); + pd->session = l2tp_session_get_nth(pd->tunnel, pd->session_idx, true); pd->session_idx++; if (pd->session == NULL) { @@ -1681,10 +1690,14 @@ static int pppol2tp_seq_show(struct seq_file *m, void *v) /* Show the tunnel or session context. */ - if (pd->session == NULL) + if (!pd->session) { pppol2tp_seq_tunnel_show(m, pd->tunnel); - else + } else { pppol2tp_seq_session_show(m, pd->session); + if (pd->session->deref) + pd->session->deref(pd->session); + l2tp_session_dec_refcount(pd->session); + } out: return 0; @@ -1843,4 +1856,4 @@ MODULE_DESCRIPTION("PPP over L2TP over UDP"); MODULE_LICENSE("GPL"); MODULE_VERSION(PPPOL2TP_DRV_VERSION); MODULE_ALIAS_NET_PF_PROTO(PF_PPPOX, PX_PROTO_OL2TP); -MODULE_ALIAS_L2TP_PWTYPE(11); +MODULE_ALIAS_L2TP_PWTYPE(7); |