rxrpc: Don't permit resending after all Tx packets acked

Once all the packets transmitted as part of a call have been acked, don't
permit any resending.
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: "David S. Miller" <davem@davemloft.net>
cc: Eric Dumazet <edumazet@google.com>
cc: Jakub Kicinski <kuba@kernel.org>
cc: Paolo Abeni <pabeni@redhat.com>
cc: linux-afs@lists.infradead.org
cc: netdev@vger.kernel.org

net/rxrpc/call_event.c

@@ -450,7 +450,9 @@ bool rxrpc_input_call_event(struct rxrpc_call *call, struct sk_buff *skb)
 		rxrpc_send_ACK(call, RXRPC_ACK_PING, 0,
 			       rxrpc_propose_ack_ping_for_lost_ack);
 
-	if (resend && __rxrpc_call_state(call) != RXRPC_CALL_CLIENT_RECV_REPLY)
+	if (resend &&
+	    __rxrpc_call_state(call) != RXRPC_CALL_CLIENT_RECV_REPLY &&
+	    !test_bit(RXRPC_CALL_TX_ALL_ACKED, &call->flags))
 		rxrpc_resend(call, NULL);
 
 	if (test_and_clear_bit(RXRPC_CALL_RX_IS_IDLE, &call->flags))