In ignore state, we let SYN goes in original, the server might respond
with RST/ACK, and that RST packet is erroneously dropped because of the
flag IP_CT_TCP_FLAG_MAXACK_SET being already set.
Signed-off-by: Ali Abdallah <aabdallah@xxxxxxx>
---
net/netfilter/nf_conntrack_proto_tcp.c | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/net/netfilter/nf_conntrack_proto_tcp.c b/net/netfilter/nf_conntrack_proto_tcp.c
index ec23330687a5..02fab7a8ec92 100644
--- a/net/netfilter/nf_conntrack_proto_tcp.c
+++ b/net/netfilter/nf_conntrack_proto_tcp.c
@@ -963,6 +963,10 @@ int nf_conntrack_tcp_packet(struct nf_conn *ct,
ct->proto.tcp.last_flags =
ct->proto.tcp.last_wscale = 0;
+ /* Reset the max ack flag so in case the server replies
+ * with RST/ACK it will not be marked as an invalid rst.
+ */
+ ct->proto.tcp.seen[dir].flags &= ~IP_CT_TCP_FLAG_MAXACK_SET;
tcp_options(skb, dataoff, th, &seen);
if (seen.flags & IP_CT_TCP_FLAG_WINDOW_SCALE) {
ct->proto.tcp.last_flags |=
--
2.26.2
