tcp: do not forget FIN in tcp_shifted_skb()

[pandora-kernel.git] / net / ipv4 / tcp_input.c

diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index 308b5b4..c1ed01e 100644 (file)
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -115,6 +115,7 @@ int sysctl_tcp_abc __read_mostly;
 #define FLAG_DSACKING_ACK      0x800 /* SACK blocks contained D-SACK info */
 #define FLAG_NONHEAD_RETRANS_ACKED     0x1000 /* Non-head rexmitted data was ACKed */
 #define FLAG_SACK_RENEGING     0x2000 /* snd_una advanced to a sacked seq */
+#define FLAG_UPDATE_TS_RECENT  0x4000 /* tcp_replace_ts_recent() */
 
 #define FLAG_ACKED             (FLAG_DATA_ACKED|FLAG_SYN_ACKED)
 #define FLAG_NOT_DUP           (FLAG_DATA|FLAG_WIN_UPDATE|FLAG_ACKED)
@@ -1468,7 +1469,10 @@ static int tcp_shifted_skb(struct sock *sk, struct sk_buff *skb,
                tp->lost_cnt_hint -= tcp_skb_pcount(prev);
        }
 
-       TCP_SKB_CB(skb)->tcp_flags |= TCP_SKB_CB(prev)->tcp_flags;
+       TCP_SKB_CB(prev)->tcp_flags |= TCP_SKB_CB(skb)->tcp_flags;
+       if (TCP_SKB_CB(skb)->tcp_flags & TCPHDR_FIN)
+               TCP_SKB_CB(prev)->end_seq++;
+
        if (skb == tcp_highest_sack(sk))
                tcp_advance_highest_sack(sk, skb);
 
@@ -2265,11 +2269,8 @@ void tcp_enter_loss(struct sock *sk, int how)
        if (tcp_is_reno(tp))
                tcp_reset_reno_sack(tp);
 
-       if (!how) {
-               /* Push undo marker, if it was plain RTO and nothing
-                * was retransmitted. */
-               tp->undo_marker = tp->snd_una;
-       } else {
+       tp->undo_marker = tp->snd_una;
+       if (how) {
                tp->sacked_out = 0;
                tp->fackets_out = 0;
        }
@@ -3635,8 +3636,7 @@ static int tcp_process_frto(struct sock *sk, int flag)
            ((tp->frto_counter >= 2) && (flag & FLAG_RETRANS_DATA_ACKED)))
                tp->undo_marker = 0;
 
-       if (!before(tp->snd_una, tp->frto_highmark) ||
-           !tcp_packets_in_flight(tp)) {
+       if (!before(tp->snd_una, tp->frto_highmark)) {
                tcp_enter_frto_loss(sk, (tp->frto_counter == 1 ? 2 : 3), flag);
                return 1;
        }
@@ -3656,6 +3656,11 @@ static int tcp_process_frto(struct sock *sk, int flag)
                }
        } else {
                if (!(flag & FLAG_DATA_ACKED) && (tp->frto_counter == 1)) {
+                       if (!tcp_packets_in_flight(tp)) {
+                               tcp_enter_frto_loss(sk, 2, flag);
+                               return true;
+                       }
+
                        /* Prevent sending of new data. */
                        tp->snd_cwnd = min(tp->snd_cwnd,
                                           tcp_packets_in_flight(tp));
@@ -3722,6 +3727,27 @@ static void tcp_send_challenge_ack(struct sock *sk)
        }
 }
 
+static void tcp_store_ts_recent(struct tcp_sock *tp)
+{
+       tp->rx_opt.ts_recent = tp->rx_opt.rcv_tsval;
+       tp->rx_opt.ts_recent_stamp = get_seconds();
+}
+
+static void tcp_replace_ts_recent(struct tcp_sock *tp, u32 seq)
+{
+       if (tp->rx_opt.saw_tstamp && !after(seq, tp->rcv_wup)) {
+               /* PAWS bug workaround wrt. ACK frames, the PAWS discard
+                * extra check below makes sure this can only happen
+                * for pure ACK frames.  -DaveM
+                *
+                * Not only, also it occurs for expired timestamps.
+                */
+
+               if (tcp_paws_check(&tp->rx_opt, 0))
+                       tcp_store_ts_recent(tp);
+       }
+}
+
 /* This routine deals with incoming acks, but not outgoing ones. */
 static int tcp_ack(struct sock *sk, const struct sk_buff *skb, int flag)
 {
@@ -3770,6 +3796,12 @@ static int tcp_ack(struct sock *sk, const struct sk_buff *skb, int flag)
        prior_fackets = tp->fackets_out;
        prior_in_flight = tcp_packets_in_flight(tp);
 
+       /* ts_recent update must be made after we are sure that the packet
+        * is in window.
+        */
+       if (flag & FLAG_UPDATE_TS_RECENT)
+               tcp_replace_ts_recent(tp, TCP_SKB_CB(skb)->seq);
+
        if (!(flag & FLAG_SLOWPATH) && after(ack, prior_snd_una)) {
                /* Window is constant, pure forward advance.
                 * No more checks are required.
@@ -4060,27 +4092,6 @@ const u8 *tcp_parse_md5sig_option(const struct tcphdr *th)
 EXPORT_SYMBOL(tcp_parse_md5sig_option);
 #endif
 
-static inline void tcp_store_ts_recent(struct tcp_sock *tp)
-{
-       tp->rx_opt.ts_recent = tp->rx_opt.rcv_tsval;
-       tp->rx_opt.ts_recent_stamp = get_seconds();
-}
-
-static inline void tcp_replace_ts_recent(struct tcp_sock *tp, u32 seq)
-{
-       if (tp->rx_opt.saw_tstamp && !after(seq, tp->rcv_wup)) {
-               /* PAWS bug workaround wrt. ACK frames, the PAWS discard
-                * extra check below makes sure this can only happen
-                * for pure ACK frames.  -DaveM
-                *
-                * Not only, also it occurs for expired timestamps.
-                */
-
-               if (tcp_paws_check(&tp->rx_opt, 0))
-                       tcp_store_ts_recent(tp);
-       }
-}
-
 /* Sorry, PAWS as specified is broken wrt. pure-ACKs -DaveM
  *
  * It is not fatal. If this ACK does _not_ change critical state (seqs, window)
@@ -5490,6 +5501,9 @@ int tcp_rcv_established(struct sock *sk, struct sk_buff *skb,
                                if (tcp_checksum_complete_user(sk, skb))
                                        goto csum_error;
 
+                               if ((int)skb->truesize > sk->sk_forward_alloc)
+                                       goto step5;
+
                                /* Predicted packet is in window by definition.
                                 * seq == rcv_nxt and rcv_wup <= rcv_nxt.
                                 * Hence, check seq<=rcv_wup reduces to:
@@ -5501,9 +5515,6 @@ int tcp_rcv_established(struct sock *sk, struct sk_buff *skb,
 
                                tcp_rcv_rtt_measure_ts(sk, skb);
 
-                               if ((int)skb->truesize > sk->sk_forward_alloc)
-                                       goto step5;
-
                                NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPHPHITS);
 
                                /* Bulk data transfer: receiver */
@@ -5551,14 +5562,10 @@ slow_path:
                return 0;
 
 step5:
-       if (th->ack && tcp_ack(sk, skb, FLAG_SLOWPATH) < 0)
+       if (th->ack &&
+           tcp_ack(sk, skb, FLAG_SLOWPATH | FLAG_UPDATE_TS_RECENT) < 0)
                goto discard;
 
-       /* ts_recent update must be made after we are sure that the packet
-        * is in window.
-        */
-       tcp_replace_ts_recent(tp, TCP_SKB_CB(skb)->seq);
-
        tcp_rcv_rtt_measure_ts(sk, skb);
 
        /* Process urgent data. */
@@ -5922,7 +5929,8 @@ int tcp_rcv_state_process(struct sock *sk, struct sk_buff *skb,
 
        /* step 5: check the ACK field */
        if (th->ack) {
-               int acceptable = tcp_ack(sk, skb, FLAG_SLOWPATH) > 0;
+               int acceptable = tcp_ack(sk, skb, FLAG_SLOWPATH |
+                                                 FLAG_UPDATE_TS_RECENT) > 0;
 
                switch (sk->sk_state) {
                case TCP_SYN_RECV:
@@ -6029,11 +6037,6 @@ int tcp_rcv_state_process(struct sock *sk, struct sk_buff *skb,
        } else
                goto discard;
 
-       /* ts_recent update must be made after we are sure that the packet
-        * is in window.
-        */
-       tcp_replace_ts_recent(tp, TCP_SKB_CB(skb)->seq);
-
        /* step 6: check the URG bit */
        tcp_urg(sk, skb, th);