1 files changed, 40 insertions, 19 deletions

diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index c6bc0c4d19c6..77ea45da0fe9 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -1591,6 +1591,34 @@ int tcp_filter(struct sock *sk, struct sk_buff *skb)
 }
 EXPORT_SYMBOL(tcp_filter);
 
+static void tcp_v4_restore_cb(struct sk_buff *skb)
+{
+        memmove(IPCB(skb), &TCP_SKB_CB(skb)->header.h4,
+                sizeof(struct inet_skb_parm));
+}
+
+static void tcp_v4_fill_cb(struct sk_buff *skb, const struct iphdr *iph,
+                           const struct tcphdr *th)
+{
+        /* This is tricky : We move IPCB at its correct location into TCP_SKB_CB()
+         * barrier() makes sure compiler wont play fool^Waliasing games.
+         */
+        memmove(&TCP_SKB_CB(skb)->header.h4, IPCB(skb),
+                sizeof(struct inet_skb_parm));
+        barrier();
+
+        TCP_SKB_CB(skb)->seq = ntohl(th->seq);
+        TCP_SKB_CB(skb)->end_seq = (TCP_SKB_CB(skb)->seq + th->syn + th->fin +
+                                    skb->len - th->doff * 4);
+        TCP_SKB_CB(skb)->ack_seq = ntohl(th->ack_seq);
+        TCP_SKB_CB(skb)->tcp_flags = tcp_flag_byte(th);
+        TCP_SKB_CB(skb)->tcp_tw_isn = 0;
+        TCP_SKB_CB(skb)->ip_dsfield = ipv4_get_dsfield(iph);
+        TCP_SKB_CB(skb)->sacked  = 0;
+        TCP_SKB_CB(skb)->has_rxtstamp =
+                        skb->tstamp || skb_hwtstamps(skb)->hwtstamp;
+}
+
 /*
  *      From tcp_input.c
  */
@@ -1631,24 +1659,6 @@ int tcp_v4_rcv(struct sk_buff *skb)
 
         th = (const struct tcphdr *)skb->data;
         iph = ip_hdr(skb);
-        /* This is tricky : We move IPCB at its correct location into TCP_SKB_CB()
-         * barrier() makes sure compiler wont play fool^Waliasing games.
-         */
-        memmove(&TCP_SKB_CB(skb)->header.h4, IPCB(skb),
-                sizeof(struct inet_skb_parm));
-        barrier();
-
-        TCP_SKB_CB(skb)->seq = ntohl(th->seq);
-        TCP_SKB_CB(skb)->end_seq = (TCP_SKB_CB(skb)->seq + th->syn + th->fin +
-                                    skb->len - th->doff * 4);
-        TCP_SKB_CB(skb)->ack_seq = ntohl(th->ack_seq);
-        TCP_SKB_CB(skb)->tcp_flags = tcp_flag_byte(th);
-        TCP_SKB_CB(skb)->tcp_tw_isn = 0;
-        TCP_SKB_CB(skb)->ip_dsfield = ipv4_get_dsfield(iph);
-        TCP_SKB_CB(skb)->sacked  = 0;
-        TCP_SKB_CB(skb)->has_rxtstamp =
-                        skb->tstamp || skb_hwtstamps(skb)->hwtstamp;
-
 lookup:
         sk = __inet_lookup_skb(&tcp_hashinfo, skb, __tcp_hdrlen(th), th->source,
                                th->dest, sdif, &refcounted);
@@ -1679,14 +1689,19 @@ process:
                 sock_hold(sk);
                 refcounted = true;
                 nsk = NULL;
-                if (!tcp_filter(sk, skb))
+                if (!tcp_filter(sk, skb)) {
+                        th = (const struct tcphdr *)skb->data;
+                        iph = ip_hdr(skb);
+                        tcp_v4_fill_cb(skb, iph, th);
                         nsk = tcp_check_req(sk, skb, req, false);
+                }
                 if (!nsk) {
                         reqsk_put(req);
                         goto discard_and_relse;
                 }
                 if (nsk == sk) {
                         reqsk_put(req);
+                        tcp_v4_restore_cb(skb);
                 } else if (tcp_child_process(sk, nsk, skb)) {
                         tcp_v4_send_reset(nsk, skb);
                         goto discard_and_relse;
@@ -1712,6 +1727,7 @@ process:
                 goto discard_and_relse;
         th = (const struct tcphdr *)skb->data;
         iph = ip_hdr(skb);
+        tcp_v4_fill_cb(skb, iph, th);
 
         skb->dev = NULL;
 
@@ -1742,6 +1758,8 @@ no_tcp_socket:
         if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb))
                 goto discard_it;
 
+        tcp_v4_fill_cb(skb, iph, th);
+
         if (tcp_checksum_complete(skb)) {
 csum_error:
                 __TCP_INC_STATS(net, TCP_MIB_CSUMERRORS);
@@ -1768,6 +1786,8 @@ do_time_wait:
                 goto discard_it;
         }
 
+        tcp_v4_fill_cb(skb, iph, th);
+
         if (tcp_checksum_complete(skb)) {
                 inet_twsk_put(inet_twsk(sk));
                 goto csum_error;
@@ -1784,6 +1804,7 @@ do_time_wait:
                 if (sk2) {
                         inet_twsk_deschedule_put(inet_twsk(sk));
                         sk = sk2;
+                        tcp_v4_restore_cb(skb);
                         refcounted = false;
                         goto process;
                 }