From b82b59ae48f1a634456fbaff15bb33b52f581ac7 Mon Sep 17 00:00:00 2001 From: Herbert Xu Date: Mon, 24 Nov 2008 16:06:50 -0800 Subject: [PATCH] bridge: netfilter: fix update_pmtu crash with GRE [ Upstream commit 631339f1e544a4d39a63cfe6708c5bddcd5a2c48 ] As GRE tries to call the update_pmtu function on skb->dst and bridge supplies an skb->dst that has a NULL ops field, all is not well. This patch fixes this by giving the bridge device an ops field with an update_pmtu function. For the moment I've left all other fields blank but we can fill them in later should the need arise. Based on report and patch by Philip Craig. Signed-off-by: Herbert Xu Signed-off-by: Patrick McHardy Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/bridge/br_netfilter.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/net/bridge/br_netfilter.c b/net/bridge/br_netfilter.c index 6a9a6cd74b1e..9abd45098f0a 100644 --- a/net/bridge/br_netfilter.c +++ b/net/bridge/br_netfilter.c @@ -101,6 +101,18 @@ static inline __be16 pppoe_proto(const struct sk_buff *skb) pppoe_proto(skb) == htons(PPP_IPV6) && \ brnf_filter_pppoe_tagged) +static void fake_update_pmtu(struct dst_entry *dst, u32 mtu) +{ +} + +static struct dst_ops fake_dst_ops = { + .family = AF_INET, + .protocol = __constant_htons(ETH_P_IP), + .update_pmtu = fake_update_pmtu, + .entry_size = sizeof(struct rtable), + .entries = ATOMIC_INIT(0), +}; + /* * Initialize bogus route table used to keep netfilter happy. * Currently, we fill in the PMTU entry because netfilter @@ -117,6 +129,7 @@ void br_netfilter_rtable_init(struct net_bridge *br) rt->u.dst.path = &rt->u.dst; rt->u.dst.metrics[RTAX_MTU - 1] = 1500; rt->u.dst.flags = DST_NOXFRM; + rt->u.dst.ops = &fake_dst_ops; } static inline struct rtable *bridge_parent_rtable(const struct net_device *dev) -- 2.39.2