[PATCH net] rxrpc: Fix terminal retransmission connection ID to include the channel

From: David Howells
Date: Wed Jun 06 2018 - 09:59:22 EST


When retransmitting the final ACK or ABORT packet for a call, the cid field
in the packet header is set to the connection's cid, but this is incorrect
as it also needs to include the channel number on that connection that the
call was made on.

Fix this by OR'ing in the channel number.

Note that this fixes the bug that:

commit 1a025028d400b23477341aa7ec2ce55f8b39b554
rxrpc: Fix handling of call quietly cancelled out on server

works around. I'm not intending to revert that as it will help protect
against problems that might occur on the server.

Fixes: 3136ef49a14c ("rxrpc: Delay terminal ACK transmission on a client call")
Signed-off-by: David Howells <dhowells@xxxxxxxxxx>
---

net/rxrpc/conn_event.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/rxrpc/conn_event.c b/net/rxrpc/conn_event.c
index 1350f1be8037..8229a52c2acd 100644
--- a/net/rxrpc/conn_event.c
+++ b/net/rxrpc/conn_event.c
@@ -70,7 +70,7 @@ static void rxrpc_conn_retransmit_call(struct rxrpc_connection *conn,
iov[2].iov_len = sizeof(ack_info);

pkt.whdr.epoch = htonl(conn->proto.epoch);
- pkt.whdr.cid = htonl(conn->proto.cid);
+ pkt.whdr.cid = htonl(conn->proto.cid | channel);
pkt.whdr.callNumber = htonl(call_id);
pkt.whdr.seq = 0;
pkt.whdr.type = chan->last_type;