neighbour: force neigh_invalidate when NUD_FAILED update is from admin

In systems where neigh gc thresh holds are set to high values,
admin deleted neigh entries (eg ip neigh flush or ip neigh del) can
linger around in NUD_FAILED state for a long time until periodic gc kicks
in. This patch forces neigh_invalidate when NUD_FAILED neigh_update is
from an admin.

Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/core/neighbour.c b/net/core/neighbour.c
index 8e3fda9e725cba97973ed2ce85ebe6f2e926e7cf..cbe85d8d4cc21239288a09927f60a08642781c3d 100644 (file)
--- a/net/core/neighbour.c
+++ b/net/core/neighbour.c
@@ -1148,7 +1148,8 @@ int neigh_update(struct neighbour *neigh, const u8 *lladdr, u8 new,
                neigh->nud_state = new;
                err = 0;
                notify = old & NUD_VALID;
-               if ((old & (NUD_INCOMPLETE | NUD_PROBE)) &&
+               if (((old & (NUD_INCOMPLETE | NUD_PROBE)) ||
+                    (flags & NEIGH_UPDATE_F_ADMIN)) &&
                    (new & NUD_FAILED)) {
                        neigh_invalidate(neigh);
                        notify = 1;