[DCCP]: Check for unread data on close

This removes one FIXME with regard to close when there is still unread data.
The mechanism is implemented similar to TCP: with regard to DCCP-specifics,
a Reset with Code 2, "Aborted" is sent to the peer.

This corresponds in part to RFC 4340, 8.1.1 and 8.1.5.

Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Signed-off-by: Ian McDonald <ian.mcdonald@jandi.co.nz>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/dccp/proto.c b/net/dccp/proto.c
index d48005f653c76002bca42bc7d6905c95023cb32e..5f47b458ed8fb3b57e432daca1f8c8b60835c245 100644 (file)
--- a/net/dccp/proto.c
+++ b/net/dccp/proto.c
@@ -891,6 +891,7 @@ void dccp_close(struct sock *sk, long timeout)
 {
        struct dccp_sock *dp = dccp_sk(sk);
        struct sk_buff *skb;
+       u32 data_was_unread = 0;
        int state;
 
        lock_sock(sk);
@@ -913,12 +914,17 @@ void dccp_close(struct sock *sk, long timeout)
         * descriptor close, not protocol-sourced closes, because the
          *reader process may not have drained the data yet!
         */
-       /* FIXME: check for unread data */
        while ((skb = __skb_dequeue(&sk->sk_receive_queue)) != NULL) {
+               data_was_unread += skb->len;
                __kfree_skb(skb);
        }
 
-       if (sock_flag(sk, SOCK_LINGER) && !sk->sk_lingertime) {
+       if (data_was_unread) {
+               /* Unread data was tossed, send an appropriate Reset Code */
+               DCCP_WARN("DCCP: ABORT -- %u bytes unread\n", data_was_unread);
+               dccp_send_reset(sk, DCCP_RESET_CODE_ABORTED);
+               dccp_set_state(sk, DCCP_CLOSED);
+       } else if (sock_flag(sk, SOCK_LINGER) && !sk->sk_lingertime) {
                /* Check zero linger _after_ checking for unread data. */
                sk->sk_prot->disconnect(sk, 0);
        } else if (dccp_close_state(sk)) {