From ee1a15922d356aff0e31bf9bb9088ab346b8033a Mon Sep 17 00:00:00 2001 From: Gerrit Renker Date: Wed, 26 Sep 2007 11:30:02 -0300 Subject: [PATCH] [DCCP]: Remove duplicate code for Reset from connected socket 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 Signed-off-by: Arnaldo Carvalho de Melo --- net/dccp/output.c | 78 ++++++++++++----------------------------------- 1 file changed, 19 insertions(+), 59 deletions(-) diff --git a/net/dccp/output.c b/net/dccp/output.c index d0c9ec6494..f4bde20562 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); } /* -- 2.39.5