net-snmp

snmpd in mater agentx mode crashed when subagent closed
TCP connection.

A TCP conection close routine is malfunction.
( at 5446 line in snmp_api.c )
It raise SIGSEGV.

5367 if (transport->flags &
NETSNMP_TRANSPORT_FLAG_STREAM) {
...
5389 newbuf =
5390 (u_char *) realloc(isp->packet,
5391
isp->packet_len + rxbuf_len);
...
5398 isp->packet = newbuf;
5399 isp->packet_size =
isp->packet_len + rxbuf_len;
5400 rxbuf = isp->packet +
isp->packet_len;
}
...
5432 if (length <= 0 && transport->flags &
NETSNMP_TRANSPORT_FLAG_STREAM) {
...
5446 SNMP_FREE(rxbuf);
...
}

5446 line must free not rxbuf but isp->packet.
< SNMP_FREE(rxbuf);
------------------
> SNMP_FREE(isp->packet);