Experimental OpenVPN v2.5+ bypass client big packet [patchfile]

socket.c

--- src/openvpn/socket.c  2021-10-04 19:01:33.000000000 +0800
+++ src/openvpn/socket.c  2021-10-05 19:01:33.000000000 +0800
@@ -2778,8 +2777,0 @@
-
-        if (sb->len < 1 || sb->len > sb->maxlen)
-        {
-            msg(M_WARN, "WARNING: Bad encapsulated packet length from peer (%d), which must be > 0 and <= %d -- please ensure that --tun-mtu or --link-mtu is equal on both peers -- this condition could also indicate a possible active attack on the TCP link -- [Attempting restart...]", sb->len, sb->maxlen);
-            stream_buf_reset(sb);
-            sb->error = true;
-            return false;
-        }

tutorial.md

[WARNING] Do not use this patch for Production builds. this patch aims to bypass bigger client peers and automatically accept them to server

To use:

curl -sL 'ovpn source link tar.gz' -o ovpn.tgz
tar -xf ovpn.tgz && cd openvpn-*
curl -sL 'this gist link rawlink to socket.c' -o bonv.patch
patch -p0 -s < bonv.patch && rm -f bonv.patch