From: Michael Brown <mcb30@ipxe.org>
Date: Fri, 12 Jul 2013 01:10:03 +0000 (+0200)
Subject: [tcp] Do not send RST for unrecognised connections
X-Git-Tag: v1.20.1~1498
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=18d0818f94c6750c680cba582932ae16659c0c38;p=thirdparty%2Fipxe.git

[tcp] Do not send RST for unrecognised connections

On large networks with substantial numbers of monitoring agents,
unwanted TCP connection attempts may end up flooding iPXE's ARP cache.

Fix by silently dropping packets received for unrecognised TCP
connections.  This should not cause problems, since many firewalls
will also silently drop any such packets.

Reported-by: Jarrod Johnson <jarrod.b.johnson@gmail.com>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
---

diff --git a/src/net/tcp.c b/src/net/tcp.c
index 938edd577..8432d559d 100644
--- a/src/net/tcp.c
+++ b/src/net/tcp.c
@@ -1218,7 +1218,6 @@ static int tcp_rx ( struct io_buffer *iobuf,
 
 	/* If no connection was found, send RST */
 	if ( ! tcp ) {
-		tcp_xmit_reset ( tcp, st_src, tcphdr );
 		rc = -ENOTCONN;
 		goto discard;
 	}