From 4e0df4951e9ecb7ec026a1330ed59f12e8937a95 Mon Sep 17 00:00:00 2001 From: Parthasarathy Bhuvaragan Date: Wed, 26 Apr 2017 10:05:01 +0200 Subject: [PATCH] tipc: improve error validations for sockets in CONNECTING state Until now, the checks for sockets in CONNECTING state was based on the assumption that the incoming message was always from the peer's accepted data socket. However an application using a non-blocking socket sends an implicit connect, this socket which is in CONNECTING state can receive error messages from the peer's listening socket. As we discard these messages, the application socket hangs as there due to inactivity. In addition to this, there are other places where we process errors but do not notify the user. In this commit, we process such incoming error messages and notify our users about them using sk_state_change(). Signed-off-by: Parthasarathy Bhuvaragan Reviewed-by: Jon Maloy Signed-off-by: David S. Miller --- net/tipc/socket.c | 25 ++++++++++++++++++++++--- 1 file changed, 22 insertions(+), 3 deletions(-) diff --git a/net/tipc/socket.c b/net/tipc/socket.c index 3b8df510a80c..38c367f6ced4 100644 --- a/net/tipc/socket.c +++ b/net/tipc/socket.c @@ -1259,7 +1259,10 @@ static int tipc_wait_for_rcvmsg(struct socket *sock, long *timeop) struct sock *sk = sock->sk; DEFINE_WAIT(wait); long timeo = *timeop; - int err; + int err = sock_error(sk); + + if (err) + return err; for (;;) { prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); @@ -1281,6 +1284,10 @@ static int tipc_wait_for_rcvmsg(struct socket *sock, long *timeop) err = sock_intr_errno(timeo); if (signal_pending(current)) break; + + err = sock_error(sk); + if (err) + break; } finish_wait(sk_sleep(sk), &wait); *timeop = timeo; @@ -1551,6 +1558,8 @@ static bool filter_connect(struct tipc_sock *tsk, struct sk_buff *skb) struct sock *sk = &tsk->sk; struct net *net = sock_net(sk); struct tipc_msg *hdr = buf_msg(skb); + u32 pport = msg_origport(hdr); + u32 pnode = msg_orignode(hdr); if (unlikely(msg_mcast(hdr))) return false; @@ -1558,18 +1567,28 @@ static bool filter_connect(struct tipc_sock *tsk, struct sk_buff *skb) switch (sk->sk_state) { case TIPC_CONNECTING: /* Accept only ACK or NACK message */ - if (unlikely(!msg_connected(hdr))) - return false; + if (unlikely(!msg_connected(hdr))) { + if (pport != tsk_peer_port(tsk) || + pnode != tsk_peer_node(tsk)) + return false; + + tipc_set_sk_state(sk, TIPC_DISCONNECTING); + sk->sk_err = ECONNREFUSED; + sk->sk_state_change(sk); + return true; + } if (unlikely(msg_errcode(hdr))) { tipc_set_sk_state(sk, TIPC_DISCONNECTING); sk->sk_err = ECONNREFUSED; + sk->sk_state_change(sk); return true; } if (unlikely(!msg_isdata(hdr))) { tipc_set_sk_state(sk, TIPC_DISCONNECTING); sk->sk_err = EINVAL; + sk->sk_state_change(sk); return true; } -- GitLab