svn commit: r232556 - stable/8/sys/netgraph

[Gleb Smirnoff]

Author: glebius
Date: Mon Mar  5 17:51:57 2012
New Revision: 232556
URL: http://svn.freebsd.org/changeset/base/232556

Log:
  Merge r231761 from head:
    In ng_bypass() add more protection against potential race
    with ng_rmnode() and its followers.

Modified:
  stable/8/sys/netgraph/ng_base.c
Directory Properties:
  stable/8/sys/   (props changed)

Modified: stable/8/sys/netgraph/ng_base.c
==============================================================================
--- stable/8/sys/netgraph/ng_base.c	Mon Mar  5 17:51:15 2012	(r232555)
+++ stable/8/sys/netgraph/ng_base.c	Mon Mar  5 17:51:57 2012	(r232556)
@@ -1169,6 +1169,10 @@ ng_bypass(hook_p hook1, hook_p hook2)
 		return (EINVAL);
 	}
 	mtx_lock(&ng_topo_mtx);
+	if (NG_HOOK_NOT_VALID(hook1) || NG_HOOK_NOT_VALID(hook2)) {
+		mtx_unlock(&ng_topo_mtx);
+		return (EINVAL);
+	}
 	hook1->hk_peer->hk_peer = hook2->hk_peer;
 	hook2->hk_peer->hk_peer = hook1->hk_peer;