[PATCH] net: tftp: Avoid sending extra ack on completion

[Ramon Fried <rfried.dev@gmail.com>]

in tftpboot, if ack was already sent previously for this
packet, don't send again.

Fixes: cc6b87ecaa96 ("net: tftp: Add client support for RFC 7440")

Reported-by: Suneel Garapati <suneelglinux@gmail.com>
Signed-off-by: Ramon Fried <rfried.dev@gmail.com>
---
 net/tftp.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/net/tftp.c b/net/tftp.c
index 03079ded34..1111834f71 100644
--- a/net/tftp.c
+++ b/net/tftp.c
@@ -678,7 +678,8 @@ static void tftp_handler(uchar *pkt, unsigned dest, struct in_addr sip,
 		}
 
 		if (len < tftp_block_size) {
-			tftp_send();
+			if (tftp_cur_block != tftp_next_ack)
+				tftp_send();
 			tftp_complete();
 		}
 		break;
-- 
2.17.1