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 aa310701e7 (openvswitch: Add gre
tunnel support.)

Signed-off-by: Wei Zhang <asuka.com@163.com>
Signed-off-by: Jesse Gross <jesse@nicira.com>
Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
This commit is contained in:
Wei Zhang 2014-06-28 12:34:53 -07:00 committed by Pravin B Shelar
parent fe984c08e2
commit e0bb8c44ed

View File

@ -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,
};