From e7eb05823806502747eadc31039cecfd7836ddeb Mon Sep 17 00:00:00 2001 From: Parthasarathy Bhuvaragan Date: Wed, 10 Oct 2018 17:50:23 +0200 Subject: [PATCH] tipc: queue socket protocol error messages into socket receive buffer In tipc_sk_filter_rcv(), when we detect protocol messages with error we call tipc_sk_conn_proto_rcv() and let it reset the connection and notify the socket by calling sk->sk_state_change(). However, tipc_sk_filter_rcv() may have been called from the function tipc_backlog_rcv(), in which case the socket lock is held and the socket already awake. This means that the sk_state_change() call is ignored and the error notification lost. Now the receive queue will remain empty and the socket sleeps forever. In this commit, we convert the protocol message into a connection abort message and enqueue it into the socket's receive queue. By this addition to the above state change we cover all conditions. Acked-by: Ying Xue Signed-off-by: Parthasarathy Bhuvaragan Signed-off-by: Jon Maloy Signed-off-by: David S. Miller --- net/tipc/socket.c | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-) diff --git a/net/tipc/socket.c b/net/tipc/socket.c index b6f99b021d09..49810fdff4c5 100644 --- a/net/tipc/socket.c +++ b/net/tipc/socket.c @@ -1196,6 +1196,7 @@ void tipc_sk_mcast_rcv(struct net *net, struct sk_buff_head *arrvq, * @skb: pointer to message buffer. */ static void tipc_sk_conn_proto_rcv(struct tipc_sock *tsk, struct sk_buff *skb, + struct sk_buff_head *inputq, struct sk_buff_head *xmitq) { struct tipc_msg *hdr = buf_msg(skb); @@ -1213,7 +1214,16 @@ static void tipc_sk_conn_proto_rcv(struct tipc_sock *tsk, struct sk_buff *skb, tipc_node_remove_conn(sock_net(sk), tsk_peer_node(tsk), tsk_peer_port(tsk)); sk->sk_state_change(sk); - goto exit; + + /* State change is ignored if socket already awake, + * - convert msg to abort msg and add to inqueue + */ + msg_set_user(hdr, TIPC_CRITICAL_IMPORTANCE); + msg_set_type(hdr, TIPC_CONN_MSG); + msg_set_size(hdr, BASIC_H_SIZE); + msg_set_hdr_sz(hdr, BASIC_H_SIZE); + __skb_queue_tail(inputq, skb); + return; } tsk->probe_unacked = false; @@ -1936,7 +1946,7 @@ static void tipc_sk_proto_rcv(struct sock *sk, switch (msg_user(hdr)) { case CONN_MANAGER: - tipc_sk_conn_proto_rcv(tsk, skb, xmitq); + tipc_sk_conn_proto_rcv(tsk, skb, inputq, xmitq); return; case SOCK_WAKEUP: tipc_dest_del(&tsk->cong_links, msg_orignode(hdr), 0); -- 2.11.0