| From 91a72a70594e5212c97705ca6a694bd307f7a26b Mon Sep 17 00:00:00 2001 |
| From: Doug Kehn <rdkehn@yahoo.com> |
| Date: Wed, 14 Jul 2010 18:02:16 -0700 |
| Subject: net/core: neighbour update Oops |
| |
| From: Doug Kehn <rdkehn@yahoo.com> |
| |
| commit 91a72a70594e5212c97705ca6a694bd307f7a26b upstream. |
| |
| When configuring DMVPN (GRE + openNHRP) and a GRE remote |
| address is configured a kernel Oops is observed. The |
| obserseved Oops is caused by a NULL header_ops pointer |
| (neigh->dev->header_ops) in neigh_update_hhs() when |
| |
| void (*update)(struct hh_cache*, const struct net_device*, const unsigned char *) |
| = neigh->dev->header_ops->cache_update; |
| |
| is executed. The dev associated with the NULL header_ops is |
| the GRE interface. This patch guards against the |
| possibility that header_ops is NULL. |
| |
| This Oops was first observed in kernel version 2.6.26.8. |
| |
| Signed-off-by: Doug Kehn <rdkehn@yahoo.com> |
| Acked-by: Eric Dumazet <eric.dumazet@gmail.com> |
| Signed-off-by: David S. Miller <davem@davemloft.net> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> |
| |
| --- |
| net/core/neighbour.c | 5 ++++- |
| 1 file changed, 4 insertions(+), 1 deletion(-) |
| |
| --- a/net/core/neighbour.c |
| +++ b/net/core/neighbour.c |
| @@ -945,7 +945,10 @@ static void neigh_update_hhs(struct neig |
| { |
| struct hh_cache *hh; |
| void (*update)(struct hh_cache*, const struct net_device*, const unsigned char *) |
| - = neigh->dev->header_ops->cache_update; |
| + = NULL; |
| + |
| + if (neigh->dev->header_ops) |
| + update = neigh->dev->header_ops->cache_update; |
| |
| if (update) { |
| for (hh = neigh->hh; hh; hh = hh->hh_next) { |
