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--- netkit-ntalk-0.17/talkd/talkd.c.orig 1999-09-29 02:04:15 +0400
+++ netkit-ntalk-0.17/talkd/talkd.c 2004-09-05 19:20:50 +0400
@@ -68,6 +68,7 @@ char talkd_rcsid[] =
#define TIMEOUT 30
#define MAXIDLE 120
+#define MINUDPSRCPORT 1024
#if !defined(MAXHOSTNAMELEN)
#define MAXHOSTNAMELEN 64
@@ -167,6 +168,7 @@ do_one_packet(void)
struct sockaddr_in sn;
int cc, i, ok;
socklen_t addrlen;
+ int theirport;
addrlen = sizeof(sn);
cc = recvfrom(0, inbuf, sizeof(inbuf), 0,
@@ -194,6 +196,12 @@ do_one_packet(void)
return;
}
+ theirport = ntohs(sn.sin_port);
+ if (theirport < MINUDPSRCPORT) {
+ syslog(LOG_WARNING, "%d: bad port", theirport);
+ return;
+ }
+
/*
* If we get here we have an address we can reply to, although
* it may not be good for much. If possible, reply to it, because
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