Avoid treating compressed MTU probes as having a negative length.

[tinc] / src / net_packet.c

diff --git a/src/net_packet.c b/src/net_packet.c
index ebf2938..9baaf4c 100644 (file)
--- a/src/net_packet.c
+++ b/src/net_packet.c
@@ -462,7 +462,10 @@ static bool receive_udppacket(node_t *n, vpn_packet_t *inpkt) {
 
                inpkt = outpkt;
 
-               origlen -= MTU / 64 + 20;
+               if (origlen > MTU / 64 + 20)
+                       origlen -= MTU / 64 + 20;
+               else
+                       origlen = 0;
        }
 
        if(inpkt->len > n->maxrecentlen) {