From e93a0435f809d009919a743fb6e93076faac8aa7 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Mon, 15 Sep 2014 04:19:52 -0700 Subject: [PATCH] tcp: allow segment with FIN in tcp_try_coalesce() We can allow a segment with FIN to be aggregated, if we take care to add tcp flags, and if skb_try_coalesce() takes care of zero sized skbs. Signed-off-by: Eric Dumazet Acked-by: Neal Cardwell Signed-off-by: David S. Miller --- net/core/skbuff.c | 3 ++- net/ipv4/tcp_input.c | 4 +--- 2 files changed, 3 insertions(+), 4 deletions(-) diff --git a/net/core/skbuff.c b/net/core/skbuff.c index c8259ac38745..29f7f0121491 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -3936,7 +3936,8 @@ bool skb_try_coalesce(struct sk_buff *to, struct sk_buff *from, return false; if (len <= skb_tailroom(to)) { - BUG_ON(skb_copy_bits(from, 0, skb_put(to, len), len)); + if (len) + BUG_ON(skb_copy_bits(from, 0, skb_put(to, len), len)); *delta_truesize = 0; return true; } diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index 8f639a4face9..228bf0c5ff19 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -4143,9 +4143,6 @@ static bool tcp_try_coalesce(struct sock *sk, *fragstolen = false; - if (tcp_hdr(from)->fin) - return false; - /* Its possible this segment overlaps with prior segment in queue */ if (TCP_SKB_CB(from)->seq != TCP_SKB_CB(to)->end_seq) return false; @@ -4158,6 +4155,7 @@ static bool tcp_try_coalesce(struct sock *sk, NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPRCVCOALESCE); TCP_SKB_CB(to)->end_seq = TCP_SKB_CB(from)->end_seq; TCP_SKB_CB(to)->ack_seq = TCP_SKB_CB(from)->ack_seq; + TCP_SKB_CB(to)->tcp_flags |= TCP_SKB_CB(from)->tcp_flags; return true; }