l2tp: fix race while getting PMTU on PPP pseudo-wire

[pandora-kernel.git] / net / l2tp / l2tp_ppp.c

diff --git a/net/l2tp/l2tp_ppp.c b/net/l2tp/l2tp_ppp.c
index 8a90d75..767bf4a 100644 (file)
--- a/net/l2tp/l2tp_ppp.c
+++ b/net/l2tp/l2tp_ppp.c
@@ -200,8 +200,6 @@ static int pppol2tp_recvmsg(struct kiocb *iocb, struct socket *sock,
        if (sk->sk_state & PPPOX_BOUND)
                goto end;
 
-       msg->msg_namelen = 0;
-
        err = 0;
        skb = skb_recv_datagram(sk, flags & ~MSG_DONTWAIT,
                                flags & MSG_DONTWAIT, &err);
@@ -350,18 +348,21 @@ static int pppol2tp_sendmsg(struct kiocb *iocb, struct socket *sock, struct msgh
        skb_put(skb, 2);
 
        /* Copy user data into skb */
-       error = memcpy_fromiovec(skb->data, m->msg_iov, total_len);
+       error = memcpy_fromiovec(skb_put(skb, total_len), m->msg_iov,
+                                total_len);
        if (error < 0) {
                kfree_skb(skb);
                goto error_put_sess_tun;
        }
-       skb_put(skb, total_len);
 
+       local_bh_disable();
        l2tp_xmit_skb(session, skb, session->hdr_len);
+       local_bh_enable();
 
        sock_put(ps->tunnel_sock);
+       sock_put(sk);
 
-       return error;
+       return total_len;
 
 error_put_sess_tun:
        sock_put(ps->tunnel_sock);
@@ -431,7 +432,9 @@ static int pppol2tp_xmit(struct ppp_channel *chan, struct sk_buff *skb)
        skb->data[0] = ppph[0];
        skb->data[1] = ppph[1];
 
+       local_bh_disable();
        l2tp_xmit_skb(session, skb, session->hdr_len);
+       local_bh_enable();
 
        sock_put(sk_tun);
        sock_put(sk);
@@ -769,9 +772,10 @@ static int pppol2tp_connect(struct socket *sock, struct sockaddr *uservaddr,
        session->deref = pppol2tp_session_sock_put;
 
        /* If PMTU discovery was enabled, use the MTU that was discovered */
-       dst = sk_dst_get(sk);
+       dst = sk_dst_get(tunnel->sock);
        if (dst != NULL) {
-               u32 pmtu = dst_mtu(__sk_dst_get(sk));
+               u32 pmtu = dst_mtu(dst);
+
                if (pmtu != 0)
                        session->mtu = session->mru = pmtu -
                                PPPOL2TP_HEADER_OVERHEAD;
@@ -915,7 +919,7 @@ static int pppol2tp_getname(struct socket *sock, struct sockaddr *uaddr,
                goto end_put_sess;
        }
 
-       inet = inet_sk(sk);
+       inet = inet_sk(tunnel->sock);
        if (tunnel->version == 2) {
                struct sockaddr_pppol2tp sp;
                len = sizeof(sp);
@@ -1348,7 +1352,7 @@ static int pppol2tp_setsockopt(struct socket *sock, int level, int optname,
        int err;
 
        if (level != SOL_PPPOL2TP)
-               return udp_prot.setsockopt(sk, level, optname, optval, optlen);
+               return -EINVAL;
 
        if (optlen < sizeof(int))
                return -EINVAL;
@@ -1474,7 +1478,7 @@ static int pppol2tp_getsockopt(struct socket *sock, int level,
        struct pppol2tp_session *ps;
 
        if (level != SOL_PPPOL2TP)
-               return udp_prot.getsockopt(sk, level, optname, optval, optlen);
+               return -EINVAL;
 
        if (get_user(len, (int __user *) optlen))
                return -EFAULT;
@@ -1777,7 +1781,8 @@ static const struct proto_ops pppol2tp_ops = {
 
 static const struct pppox_proto pppol2tp_proto = {
        .create         = pppol2tp_create,
-       .ioctl          = pppol2tp_ioctl
+       .ioctl          = pppol2tp_ioctl,
+       .owner          = THIS_MODULE,
 };
 
 #ifdef CONFIG_L2TP_V3