In this patch, duplicated code is removed for the case when a Reset packet is
sent from a connected socket. This code duplication is between dccp_make_reset
and dccp_transmit_skb, which already contained an (up to now entirely unused)
switch statement to fill in the reset code from the DCCP_SKB_CB.
The only thing that has been removed is the call to dst_clone(dst), since
the queue_xmit functions use sk_dst_cache anyway.
I wasn't sure which purpose inet_sk_rebuild_header served, so I left it in.
Signed-off-by: Gerrit Renker <gerrit@xxxxxxxxxxxxxx>
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxxxxxxxxxx>
---
net/dccp/output.c | 78 +++++++++++++----------------------------------------
1 files changed, 19 insertions(+), 59 deletions(-)
diff --git a/net/dccp/output.c b/net/dccp/output.c
index d0c9ec6..f4bde20 100644
--- a/net/dccp/output.c
+++ b/net/dccp/output.c
@@ -61,6 +61,7 @@ static int dccp_transmit_skb(struct sock *sk, struct sk_buff *skb)
set_ack = 0;
/* fall through */
case DCCP_PKT_DATAACK:
+ case DCCP_PKT_RESET:
break;
case DCCP_PKT_REQUEST:
@@ -73,8 +74,10 @@ static int dccp_transmit_skb(struct sock *sk, struct sk_buff *skb)
/* fall through */
default:
/*
- * Only data packets should come through with skb->sk
- * set.
+ * Set owner/destructor: some skbs are allocated via
+ * alloc_skb (e.g. when retransmission may happen).
+ * Only Data, DataAck, and Reset packets should come
+ * through here with skb->sk set.
*/
WARN_ON(skb->sk);
skb_set_owner_w(skb, sk);
@@ -324,72 +327,29 @@ struct sk_buff *dccp_make_response(struct sock *sk, struct dst_entry *dst,
EXPORT_SYMBOL_GPL(dccp_make_response);
-static struct sk_buff *dccp_make_reset(struct sock *sk, struct dst_entry *dst,
- const enum dccp_reset_codes code)
-{
- struct dccp_hdr *dh;
- struct dccp_sock *dp = dccp_sk(sk);
- const u32 dccp_header_size = sizeof(struct dccp_hdr) +
- sizeof(struct dccp_hdr_ext) +
- sizeof(struct dccp_hdr_reset);
- struct sk_buff *skb = sock_wmalloc(sk, sk->sk_prot->max_header, 1,
- GFP_ATOMIC);
- if (skb == NULL)
- return NULL;
-
- /* Reserve space for headers. */
- skb_reserve(skb, sk->sk_prot->max_header);
-
- skb->dst = dst_clone(dst);
-
- dccp_inc_seqno(&dp->dccps_gss);
-
- DCCP_SKB_CB(skb)->dccpd_reset_code = code;
- DCCP_SKB_CB(skb)->dccpd_type = DCCP_PKT_RESET;
- DCCP_SKB_CB(skb)->dccpd_seq = dp->dccps_gss;
-
- if (dccp_insert_options(sk, skb)) {
- kfree_skb(skb);
- return NULL;
- }
-
- dh = dccp_zeroed_hdr(skb, dccp_header_size);
-
- dh->dccph_sport = inet_sk(sk)->sport;
- dh->dccph_dport = inet_sk(sk)->dport;
- dh->dccph_doff = (dccp_header_size +
- DCCP_SKB_CB(skb)->dccpd_opt_len) / 4;
- dh->dccph_type = DCCP_PKT_RESET;
- dh->dccph_x = 1;
- dccp_hdr_set_seq(dh, dp->dccps_gss);
- dccp_hdr_set_ack(dccp_hdr_ack_bits(skb), dp->dccps_gsr);
-
- dccp_hdr_reset(skb)->dccph_reset_code = code;
- inet_csk(sk)->icsk_af_ops->send_check(sk, 0, skb);
-
- DCCP_INC_STATS(DCCP_MIB_OUTSEGS);
- return skb;
-}
-
+/* send Reset on established socket, to close or abort the connection */
int dccp_send_reset(struct sock *sk, enum dccp_reset_codes code)
{
+ struct sk_buff *skb;
/*
* FIXME: what if rebuild_header fails?
* Should we be doing a rebuild_header here?
*/
int err = inet_sk_rebuild_header(sk);
- if (err == 0) {
- struct sk_buff *skb = dccp_make_reset(sk, sk->sk_dst_cache,
- code);
- if (skb != NULL) {
- memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
- err = inet_csk(sk)->icsk_af_ops->queue_xmit(skb, 0);
- return net_xmit_eval(err);
- }
- }
+ if (err != 0)
+ return err;
+
+ skb = sock_wmalloc(sk, sk->sk_prot->max_header, 1, GFP_ATOMIC);
+ if (skb == NULL)
+ return -ENOBUFS;
+
+ /* Reserve space for headers and prepare control bits. */
+ skb_reserve(skb, sk->sk_prot->max_header);
+ DCCP_SKB_CB(skb)->dccpd_type = DCCP_PKT_RESET;
+ DCCP_SKB_CB(skb)->dccpd_reset_code = code;
- return err;
+ return dccp_transmit_skb(sk, skb);
}
/*
--
1.5.2.2
-
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