From e0bb8c44ed5cfcc56b571758ed966ee48779024c Mon Sep 17 00:00:00 2001 From: Wei Zhang Date: Sat, 28 Jun 2014 12:34:53 -0700 Subject: [PATCH] openvswitch: supply a dummy err_handler of gre_cisco_protocol to prevent kernel crash When use gre vport, openvswitch register a gre_cisco_protocol but does not supply a err_handler with it. The gre_cisco_err() in net/ipv4/gre_demux.c expect err_handler be provided with the gre_cisco_protocol implementation, and call ->err_handler() without existence check, cause the kernel crash. This patch provide a err_handler to fix this bug. This bug introduced by commit aa310701e787087d (openvswitch: Add gre tunnel support.) Signed-off-by: Wei Zhang Signed-off-by: Jesse Gross Signed-off-by: Pravin B Shelar --- net/openvswitch/vport-gre.c | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) diff --git a/net/openvswitch/vport-gre.c b/net/openvswitch/vport-gre.c index 35ec4fe..f49148a 100644 --- a/net/openvswitch/vport-gre.c +++ b/net/openvswitch/vport-gre.c @@ -110,6 +110,22 @@ static int gre_rcv(struct sk_buff *skb, return PACKET_RCVD; } +/* Called with rcu_read_lock and BH disabled. */ +static int gre_err(struct sk_buff *skb, u32 info, + const struct tnl_ptk_info *tpi) +{ + struct ovs_net *ovs_net; + struct vport *vport; + + ovs_net = net_generic(dev_net(skb->dev), ovs_net_id); + vport = rcu_dereference(ovs_net->vport_net.gre_vport); + + if (unlikely(!vport)) + return PACKET_REJECT; + else + return PACKET_RCVD; +} + static int gre_tnl_send(struct vport *vport, struct sk_buff *skb) { struct net *net = ovs_dp_get_net(vport->dp); @@ -186,6 +202,7 @@ error: static struct gre_cisco_protocol gre_protocol = { .handler = gre_rcv, + .err_handler = gre_err, .priority = 1, }; -- 2.7.4