ospfd: avoid exhausting memory with OSPF vertices (BZ#476)

This was found in scale testing at OSR;  ospfd is adding the same link
over and over again to the SPF tree.  This fix prevents the resulting
memory corruption from happening and adds a debug message to track
occurence of this issue and/or confirm a proper fix.

(This version was improved by Scott Feldman over the earlier RFC.)

* ospfd/ospf_spf.c: (ospf_spf_add_parent) loop over existing vertices
  and refuse to add duplicates.

Tested-by: Martin Winter <mwinter@opensourcerouting.org>
Signed-off-by: Scott Feldman <sfeldma@cumulusnetworks.com>
Signed-off-by: David Lamparter <equinox@opensourcerouting.org>
This commit is contained in:
David Lamparter 2012-07-23 18:17:57 +02:00
parent aa5cf24b9d
commit 7b92589c22

View File

@ -422,7 +422,8 @@ ospf_spf_add_parent (struct vertex *v, struct vertex *w,
struct vertex_nexthop *newhop,
unsigned int distance)
{
struct vertex_parent *vp;
struct vertex_parent *vp, *wp;
struct listnode *node;
/* we must have a newhop, and a distance */
assert (v && w && newhop);
@ -456,7 +457,19 @@ ospf_spf_add_parent (struct vertex *v, struct vertex *w,
w->distance = distance;
}
/* new parent is <= existing parents, add it to parent list */
/* new parent is <= existing parents, add it to parent list (if nexthop
* not on parent list)
*/
for (ALL_LIST_ELEMENTS_RO(w->parents, node, wp))
{
if (memcmp(newhop, wp->nexthop, sizeof(*newhop)) == 0)
{
if (IS_DEBUG_OSPF_EVENT)
zlog_debug ("%s: ... nexthop already on parent list, skipping add", __func__);
return;
}
}
vp = vertex_parent_new (v, ospf_lsa_has_link (w->lsa, v->lsa), newhop);
listnode_add (w->parents, vp);