1 files changed, 51 insertions, 25 deletions

diff --git a/net/ipv4/tcp_minisocks.c b/net/ipv4/tcp_minisocks.c
index 4c03598ed924..87accec8d097 100644
--- a/net/ipv4/tcp_minisocks.c
+++ b/net/ipv4/tcp_minisocks.c
@@ -26,13 +26,7 @@
 #include <net/inet_common.h>
 #include <net/xfrm.h>
 
-#ifdef CONFIG_SYSCTL
-#define SYNC_INIT 0 /* let the user enable it */
-#else
-#define SYNC_INIT 1
-#endif
-
-int sysctl_tcp_syncookies __read_mostly = SYNC_INIT;
+int sysctl_tcp_syncookies __read_mostly = 1;
 EXPORT_SYMBOL(sysctl_tcp_syncookies);
 
 int sysctl_tcp_abort_on_overflow __read_mostly;
@@ -96,13 +90,14 @@ enum tcp_tw_status
 tcp_timewait_state_process(struct inet_timewait_sock *tw, struct sk_buff *skb,
                            const struct tcphdr *th)
 {
-        struct tcp_timewait_sock *tcptw = tcp_twsk((struct sock *)tw);
         struct tcp_options_received tmp_opt;
+        u8 *hash_location;
+        struct tcp_timewait_sock *tcptw = tcp_twsk((struct sock *)tw);
         int paws_reject = 0;
 
-        tmp_opt.saw_tstamp = 0;
         if (th->doff > (sizeof(*th) >> 2) && tcptw->tw_ts_recent_stamp) {
-                tcp_parse_options(skb, &tmp_opt, 0);
+                tmp_opt.tstamp_ok = 1;
+                tcp_parse_options(skb, &tmp_opt, &hash_location, 1, NULL);
 
                 if (tmp_opt.saw_tstamp) {
                         tmp_opt.ts_recent       = tcptw->tw_ts_recent;
@@ -389,14 +384,43 @@ struct sock *tcp_create_openreq_child(struct sock *sk, struct request_sock *req,
                 const struct inet_request_sock *ireq = inet_rsk(req);
                 struct tcp_request_sock *treq = tcp_rsk(req);
                 struct inet_connection_sock *newicsk = inet_csk(newsk);
-                struct tcp_sock *newtp;
+                struct tcp_sock *newtp = tcp_sk(newsk);
+                struct tcp_sock *oldtp = tcp_sk(sk);
+                struct tcp_cookie_values *oldcvp = oldtp->cookie_values;
+
+                /* TCP Cookie Transactions require space for the cookie pair,
+                 * as it differs for each connection.  There is no need to
+                 * copy any s_data_payload stored at the original socket.
+                 * Failure will prevent resuming the connection.
+                 *
+                 * Presumed copied, in order of appearance:
+                 *      cookie_in_always, cookie_out_never
+                 */
+                if (oldcvp != NULL) {
+                        struct tcp_cookie_values *newcvp =
+                                kzalloc(sizeof(*newtp->cookie_values),
+                                        GFP_ATOMIC);
+
+                        if (newcvp != NULL) {
+                                kref_init(&newcvp->kref);
+                                newcvp->cookie_desired =
+                                                oldcvp->cookie_desired;
+                                newtp->cookie_values = newcvp;
+                        } else {
+                                /* Not Yet Implemented */
+                                newtp->cookie_values = NULL;
+                        }
+                }
 
                 /* Now setup tcp_sock */
-                newtp = tcp_sk(newsk);
                 newtp->pred_flags = 0;
-                newtp->rcv_wup = newtp->copied_seq = newtp->rcv_nxt = treq->rcv_isn + 1;
-                newtp->snd_sml = newtp->snd_una = newtp->snd_nxt = treq->snt_isn + 1;
-                newtp->snd_up = treq->snt_isn + 1;
+
+                newtp->rcv_wup = newtp->copied_seq =
+                newtp->rcv_nxt = treq->rcv_isn + 1;
+
+                newtp->snd_sml = newtp->snd_una =
+                newtp->snd_nxt = newtp->snd_up =
+                        treq->snt_isn + 1 + tcp_s_data_size(oldtp);
 
                 tcp_prequeue_init(newtp);
 
@@ -429,8 +453,8 @@ struct sock *tcp_create_openreq_child(struct sock *sk, struct request_sock *req,
                 tcp_set_ca_state(newsk, TCP_CA_Open);
                 tcp_init_xmit_timers(newsk);
                 skb_queue_head_init(&newtp->out_of_order_queue);
-                newtp->write_seq = treq->snt_isn + 1;
-                newtp->pushed_seq = newtp->write_seq;
+                newtp->write_seq = newtp->pushed_seq =
+                        treq->snt_isn + 1 + tcp_s_data_size(oldtp);
 
                 newtp->rx_opt.saw_tstamp = 0;
 
@@ -476,7 +500,7 @@ struct sock *tcp_create_openreq_child(struct sock *sk, struct request_sock *req,
                 if (newtp->af_specific->md5_lookup(sk, newsk))
                         newtp->tcp_header_len += TCPOLEN_MD5SIG_ALIGNED;
 #endif
-                if (skb->len >= TCP_MIN_RCVMSS+newtp->tcp_header_len)
+                if (skb->len >= TCP_MSS_DEFAULT + newtp->tcp_header_len)
                         newicsk->icsk_ack.last_seg_size = skb->len - newtp->tcp_header_len;
                 newtp->rx_opt.mss_clamp = req->mss;
                 TCP_ECN_openreq_child(newtp, req);
@@ -495,15 +519,16 @@ struct sock *tcp_check_req(struct sock *sk, struct sk_buff *skb,
                            struct request_sock *req,
                            struct request_sock **prev)
 {
+        struct tcp_options_received tmp_opt;
+        u8 *hash_location;
+        struct sock *child;
         const struct tcphdr *th = tcp_hdr(skb);
         __be32 flg = tcp_flag_word(th) & (TCP_FLAG_RST|TCP_FLAG_SYN|TCP_FLAG_ACK);
         int paws_reject = 0;
-        struct tcp_options_received tmp_opt;
-        struct sock *child;
 
-        tmp_opt.saw_tstamp = 0;
-        if (th->doff > (sizeof(struct tcphdr)>>2)) {
-                tcp_parse_options(skb, &tmp_opt, 0);
+        if ((th->doff > (sizeof(*th) >> 2)) && (req->ts_recent)) {
+                tmp_opt.tstamp_ok = 1;
+                tcp_parse_options(skb, &tmp_opt, &hash_location, 1, NULL);
 
                 if (tmp_opt.saw_tstamp) {
                         tmp_opt.ts_recent = req->ts_recent;
@@ -537,7 +562,7 @@ struct sock *tcp_check_req(struct sock *sk, struct sk_buff *skb,
                  * Enforce "SYN-ACK" according to figure 8, figure 6
                  * of RFC793, fixed by RFC1122.
                  */
-                req->rsk_ops->rtx_syn_ack(sk, req);
+                req->rsk_ops->rtx_syn_ack(sk, req, NULL);
                 return NULL;
         }
 
@@ -596,7 +621,8 @@ struct sock *tcp_check_req(struct sock *sk, struct sk_buff *skb,
          * Invalid ACK: reset will be sent by listening socket
          */
         if ((flg & TCP_FLAG_ACK) &&
-            (TCP_SKB_CB(skb)->ack_seq != tcp_rsk(req)->snt_isn + 1))
+            (TCP_SKB_CB(skb)->ack_seq !=
+             tcp_rsk(req)->snt_isn + 1 + tcp_s_data_size(tcp_sk(sk))))
                 return sk;
 
         /* Also, it would be not so bad idea to check rcv_tsecr, which