Commit 28b2774a authored by Eric Dumazet's avatar Eric Dumazet Committed by David S. Miller

tcp: Fix tcp_make_synack()

Commit 4957faad (TCPCT part 1g: Responder Cookie => Initiator), part
of TCP_COOKIE_TRANSACTION implementation, forgot to correctly size
synack skb in case user data must be included.

Many thanks to Mika Pentillä for spotting this error.
Reported-by: default avatarPenttillä Mika <mika.penttila@ixonos.com>
Signed-off-by: default avatarEric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 98376387
......@@ -2395,13 +2395,17 @@ struct sk_buff *tcp_make_synack(struct sock *sk, struct dst_entry *dst,
struct tcp_extend_values *xvp = tcp_xv(rvp);
struct inet_request_sock *ireq = inet_rsk(req);
struct tcp_sock *tp = tcp_sk(sk);
const struct tcp_cookie_values *cvp = tp->cookie_values;
struct tcphdr *th;
struct sk_buff *skb;
struct tcp_md5sig_key *md5;
int tcp_header_size;
int mss;
int s_data_desired = 0;
skb = sock_wmalloc(sk, MAX_TCP_HEADER + 15, 1, GFP_ATOMIC);
if (cvp != NULL && cvp->s_data_constant && cvp->s_data_desired)
s_data_desired = cvp->s_data_desired;
skb = sock_wmalloc(sk, MAX_TCP_HEADER + 15 + s_data_desired, 1, GFP_ATOMIC);
if (skb == NULL)
return NULL;
......@@ -2457,16 +2461,12 @@ struct sk_buff *tcp_make_synack(struct sock *sk, struct dst_entry *dst,
TCPCB_FLAG_SYN | TCPCB_FLAG_ACK);
if (OPTION_COOKIE_EXTENSION & opts.options) {
const struct tcp_cookie_values *cvp = tp->cookie_values;
if (cvp != NULL &&
cvp->s_data_constant &&
cvp->s_data_desired > 0) {
u8 *buf = skb_put(skb, cvp->s_data_desired);
if (s_data_desired) {
u8 *buf = skb_put(skb, s_data_desired);
/* copy data directly from the listening socket. */
memcpy(buf, cvp->s_data_payload, cvp->s_data_desired);
TCP_SKB_CB(skb)->end_seq += cvp->s_data_desired;
memcpy(buf, cvp->s_data_payload, s_data_desired);
TCP_SKB_CB(skb)->end_seq += s_data_desired;
}
if (opts.hash_size > 0) {
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment