ospfd: CVE-2011-3326 (uknown LSA type segfault)

This vulnerability (CERT-FI #514837) was reported by CROSS project.
They have also suggested a fix to the problem, which was found
acceptable.

Quagga ospfd does not seem to handle unknown LSA types in a Link State
Update message correctly. If LSA type is something else than one
supported
by Quagga, the default handling of unknown types leads to an error.

* ospf_flood.c
  * ospf_flood(): check return value of ospf_lsa_install()

diff --git a/ospfd/ospf_flood.c b/ospfd/ospf_flood.c
index 41661da2f46c44fe3523c84b0bf2dbdb78d4a682..fc0bbf1268bae846f4d6e661a119881101547bf0 100644 (file)
--- a/ospfd/ospf_flood.c
+++ b/ospfd/ospf_flood.c
@@ -319,7 +319,8 @@ ospf_flood (struct ospf *ospf, struct ospf_neighbor *nbr,
      procedure cannot overwrite the newly installed LSA until
      MinLSArrival seconds have elapsed. */  
 
-  new = ospf_lsa_install (ospf, nbr->oi, new);
+  if (! (new = ospf_lsa_install (ospf, nbr->oi, new)))
+    return 0; /* unknown LSA type */
 
   /* Acknowledge the receipt of the LSA by sending a Link State
      Acknowledgment packet back out the receiving interface. */