diff options
Diffstat (limited to 'net/l2tp')
| -rw-r--r-- | net/l2tp/l2tp_ppp.c | 67 |
1 files changed, 18 insertions, 49 deletions
diff --git a/net/l2tp/l2tp_ppp.c b/net/l2tp/l2tp_ppp.c index 1c6da02f976a..b403728e2757 100644 --- a/net/l2tp/l2tp_ppp.c +++ b/net/l2tp/l2tp_ppp.c @@ -553,7 +553,6 @@ static void pppol2tp_show(struct seq_file *m, void *arg) static void pppol2tp_session_init(struct l2tp_session *session) { struct pppol2tp_session *ps; - u32 mtu; session->recv_skb = pppol2tp_recv; #if IS_ENABLED(CONFIG_L2TP_DEBUGFS) @@ -563,11 +562,6 @@ static void pppol2tp_session_init(struct l2tp_session *session) ps = l2tp_session_priv(session); mutex_init(&ps->sk_lock); ps->owner = current->pid; - - /* If PMTU discovery was enabled, use the MTU that was discovered */ - mtu = l2tp_tunnel_dst_mtu(session->tunnel); - if (mtu) - session->mtu = mtu - PPPOL2TP_HEADER_OVERHEAD; } struct l2tp_connect_info { @@ -654,6 +648,22 @@ static int pppol2tp_sockaddr_get_info(const void *sa, int sa_len, return 0; } +/* Rough estimation of the maximum payload size a tunnel can transmit without + * fragmenting at the lower IP layer. Assumes L2TPv2 with sequence + * numbers and no IP option. Not quite accurate, but the result is mostly + * unused anyway. + */ +static int pppol2tp_tunnel_mtu(const struct l2tp_tunnel *tunnel) +{ + int mtu; + + mtu = l2tp_tunnel_dst_mtu(tunnel); + if (mtu <= PPPOL2TP_HEADER_OVERHEAD) + return 1500 - PPPOL2TP_HEADER_OVERHEAD; + + return mtu - PPPOL2TP_HEADER_OVERHEAD; +} + /* connect() handler. Attach a PPPoX socket to a tunnel UDP socket */ static int pppol2tp_connect(struct socket *sock, struct sockaddr *uservaddr, @@ -771,8 +781,6 @@ static int pppol2tp_connect(struct socket *sock, struct sockaddr *uservaddr, goto end; } } else { - /* Default MTU must allow space for UDP/L2TP/PPP headers */ - cfg.mtu = 1500 - PPPOL2TP_HEADER_OVERHEAD; cfg.pw_type = L2TP_PWTYPE_PPP; session = l2tp_session_create(sizeof(struct pppol2tp_session), @@ -817,7 +825,7 @@ static int pppol2tp_connect(struct socket *sock, struct sockaddr *uservaddr, po->chan.private = sk; po->chan.ops = &pppol2tp_chan_ops; - po->chan.mtu = session->mtu; + po->chan.mtu = pppol2tp_tunnel_mtu(tunnel); error = ppp_register_net_channel(sock_net(sk), &po->chan); if (error) { @@ -873,10 +881,6 @@ static int pppol2tp_session_create(struct net *net, struct l2tp_tunnel *tunnel, goto err; } - /* Default MTU values. */ - if (cfg->mtu == 0) - cfg->mtu = 1500 - PPPOL2TP_HEADER_OVERHEAD; - /* Allocate and initialize a new session context. */ session = l2tp_session_create(sizeof(struct pppol2tp_session), tunnel, session_id, @@ -1040,7 +1044,6 @@ static void pppol2tp_copy_stats(struct pppol2tp_ioc_stats *dest, static int pppol2tp_session_ioctl(struct l2tp_session *session, unsigned int cmd, unsigned long arg) { - struct ifreq ifr; int err = 0; struct sock *sk; int val = (int) arg; @@ -1056,39 +1059,6 @@ static int pppol2tp_session_ioctl(struct l2tp_session *session, return -EBADR; switch (cmd) { - case SIOCGIFMTU: - err = -ENXIO; - if (!(sk->sk_state & PPPOX_CONNECTED)) - break; - - err = -EFAULT; - if (copy_from_user(&ifr, (void __user *) arg, sizeof(struct ifreq))) - break; - ifr.ifr_mtu = session->mtu; - if (copy_to_user((void __user *) arg, &ifr, sizeof(struct ifreq))) - break; - - l2tp_info(session, L2TP_MSG_CONTROL, "%s: get mtu=%d\n", - session->name, session->mtu); - err = 0; - break; - - case SIOCSIFMTU: - err = -ENXIO; - if (!(sk->sk_state & PPPOX_CONNECTED)) - break; - - err = -EFAULT; - if (copy_from_user(&ifr, (void __user *) arg, sizeof(struct ifreq))) - break; - - session->mtu = ifr.ifr_mtu; - - l2tp_info(session, L2TP_MSG_CONTROL, "%s: set mtu=%d\n", - session->name, session->mtu); - err = 0; - break; - case PPPIOCGMRU: case PPPIOCGFLAGS: err = -EFAULT; @@ -1685,8 +1655,7 @@ static void pppol2tp_seq_session_show(struct seq_file *m, void *v) tunnel->peer_tunnel_id, session->peer_session_id, state, user_data_ok); - seq_printf(m, " %d/0/%c/%c/%s %08x %u\n", - session->mtu, + seq_printf(m, " 0/0/%c/%c/%s %08x %u\n", session->recv_seq ? 'R' : '-', session->send_seq ? 'S' : '-', session->lns_mode ? "LNS" : "LAC", |