aboutsummaryrefslogtreecommitdiffstats
path: root/net/netfilter/nf_conntrack_proto_tcp.c
diff options
context:
space:
mode:
Diffstat (limited to 'net/netfilter/nf_conntrack_proto_tcp.c')
-rw-r--r--net/netfilter/nf_conntrack_proto_tcp.c19
1 files changed, 13 insertions, 6 deletions
diff --git a/net/netfilter/nf_conntrack_proto_tcp.c b/net/netfilter/nf_conntrack_proto_tcp.c
index 1926fd56df56..848b137151c2 100644
--- a/net/netfilter/nf_conntrack_proto_tcp.c
+++ b/net/netfilter/nf_conntrack_proto_tcp.c
@@ -541,13 +541,20 @@ static bool tcp_in_window(const struct nf_conn *ct,
swin = win << sender->td_scale;
sender->td_maxwin = (swin == 0 ? 1 : swin);
sender->td_maxend = end + sender->td_maxwin;
- /*
- * We haven't seen traffic in the other direction yet
- * but we have to tweak window tracking to pass III
- * and IV until that happens.
- */
- if (receiver->td_maxwin == 0)
+ if (receiver->td_maxwin == 0) {
+ /* We haven't seen traffic in the other
+ * direction yet but we have to tweak window
+ * tracking to pass III and IV until that
+ * happens.
+ */
receiver->td_end = receiver->td_maxend = sack;
+ } else if (sack == receiver->td_end + 1) {
+ /* Likely a reply to a keepalive.
+ * Needed for III.
+ */
+ receiver->td_end++;
+ }
+
}
} else if (((state->state == TCP_CONNTRACK_SYN_SENT
&& dir == IP_CT_DIR_ORIGINAL)