ospfd: CVE-2011-3325 part 1 (OSPF header underrun)
This vulnerability (CERT-FI #514838) was reported by CROSS project.
When only 14 first bytes of a Hello packet is delivered, ospfd crashes.
* ospf_packet.c
* ospf_read(): add size check
diff --git a/ospfd/ospf_packet.c b/ospfd/ospf_packet.c
index be137d9..5727878 100644
--- a/ospfd/ospf_packet.c
+++ b/ospfd/ospf_packet.c
@@ -2430,10 +2430,19 @@
return 0;
}
- /* Adjust size to message length. */
+ /* Advance from IP header to OSPF header (iph->ip_hl has been verified
+ by ospf_recv_packet() to be correct). */
stream_forward_getp (ibuf, iph->ip_hl * 4);
-
- /* Get ospf packet header. */
+
+ /* Make sure the OSPF header is really there. */
+ if (stream_get_endp (ibuf) - stream_get_getp (ibuf) < OSPF_HEADER_SIZE)
+ {
+ zlog_debug ("ospf_read: ignored OSPF packet with undersized (%u bytes) header",
+ stream_get_endp (ibuf) - stream_get_getp (ibuf));
+ return -1;
+ }
+
+ /* Now it is safe to access all fields of OSPF packet header. */
ospfh = (struct ospf_header *) STREAM_PNT (ibuf);
/* associate packet with ospf interface */