[RFC v2 01/14] tcp: Write options after the header has been fully done
flat view
STALE3191d
REVIEWED: 1 (0M)
From: Christoph Paasch <hidden>
Date: 2018-02-01 00:07:26
Subsystem:
networking [general], networking [tcp], the rest · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Neal Cardwell, Linus Torvalds
Status: Reviewed.
Revision v2 (2 revisions archived); 1 review trailer.
Revisions (2)
- rfc
- v2 current [diff against previous]
The generic TCP-option framework will need to have access to the full TCP-header (e.g., if we want to compute a checksum for TCP-MD5). Thus, we move the call to tcp_options_write() to after all the fields in the header have been filled out. Signed-off-by: Christoph Paasch <redacted> Reviewed-by: Mat Martineau <redacted> --- net/ipv4/tcp_output.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index e9f985e42405..df50c7dc1a43 100644
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c@@ -1126,7 +1126,6 @@ static int tcp_transmit_skb(struct sock *sk, struct sk_buff *skb, int clone_it, } } - tcp_options_write((__be32 *)(th + 1), tp, &opts); skb_shinfo(skb)->gso_type = sk->sk_gso_type; if (likely(!(tcb->tcp_flags & TCPHDR_SYN))) { th->window = htons(tcp_select_window(sk));
@@ -1137,6 +1136,7 @@ static int tcp_transmit_skb(struct sock *sk, struct sk_buff *skb, int clone_it, */ th->window = htons(min(tp->rcv_wnd, 65535U)); } + tcp_options_write((__be32 *)(th + 1), tp, &opts); #ifdef CONFIG_TCP_MD5SIG /* Calculate the MD5 hash, as we have all we need now */ if (md5) {
@@ -3247,8 +3247,8 @@ struct sk_buff *tcp_make_synack(const struct sock *sk, struct dst_entry *dst, /* RFC1323: The window in SYN & SYN/ACK segments is never scaled. */ th->window = htons(min(req->rsk_rcv_wnd, 65535U)); - tcp_options_write((__be32 *)(th + 1), NULL, &opts); th->doff = (tcp_header_size >> 2); + tcp_options_write((__be32 *)(th + 1), NULL, &opts); __TCP_INC_STATS(sock_net(sk), TCP_MIB_OUTSEGS); #ifdef CONFIG_TCP_MD5SIG
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2.16.1