Commit 7cf87fa2 authored Nov 01, 2016 by Parthasarathy Bhuvaragan Committed by David S. Miller Nov 01, 2016

tipc: return early for non-blocking sockets at link congestion



Until now, in stream/mcast send() we pass the message to the link
layer even when the link is congested and add the socket to the
link's wakeup queue. This is unnecessary for non-blocking sockets.
If a socket is set to non-blocking and sends multicast with zero
back off time while receiving EAGAIN, we exhaust the memory.

In this commit, we return immediately at stream/mcast send() for
non-blocking sockets.

Acked-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: Parthasarathy Bhuvaragan <parthasarathy.bhuvaragan@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

parent 169650d3

net/tipc/socket.c

+6 −0

Original line number	Diff line number	Diff line
		@@ -697,6 +697,9 @@ static int tipc_sendmcast(struct socket sock, struct tipc_name_seq seq,
		uint mtu;
		int rc;

		if (!timeo && tsk->link_cong)
		return -ELINKCONG;

		msg_set_type(mhdr, TIPC_MCAST_MSG);
		msg_set_lookup_scope(mhdr, TIPC_CLUSTER_SCOPE);
		msg_set_destport(mhdr, 0);
		@@ -1072,6 +1075,9 @@ static int __tipc_send_stream(struct socket sock, struct msghdr m, size_t dsz)
		}

		timeo = sock_sndtimeo(sk, m->msg_flags & MSG_DONTWAIT);
		if (!timeo && tsk->link_cong)
		return -ELINKCONG;

		dnode = tsk_peer_node(tsk);
		skb_queue_head_init(&pktchain);