From 7d17343155535ec0be36ad283637ea1f4a3bce9c Mon Sep 17 00:00:00 2001
From: zouyonghao <yonghaoz1994@gmail.com>
Date: Wed, 21 Oct 2020 21:39:20 +0800
Subject: [PATCH] Accept the packet with seq smaller than the last received
 packet

---
 mtcp/src/tcp_ring_buffer.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/mtcp/src/tcp_ring_buffer.c b/mtcp/src/tcp_ring_buffer.c
index 6b98fa4ce..5db60441b 100644
--- a/mtcp/src/tcp_ring_buffer.c
+++ b/mtcp/src/tcp_ring_buffer.c
@@ -294,6 +294,12 @@ RBPut(rb_manager_t rbm, struct tcp_ring_buffer* buff,
 	struct fragment_ctx* prev, *pprev;
 	int merged = 0;
 
+	if (cur_seq < buff->head_seq) {
+		len -= buff->head_seq - cur_seq;
+		data += buff->head_seq - cur_seq;
+		cur_seq = buff->head_seq;
+	}
+
 	if (len <= 0)
 		return 0;