[PATCH net] net: openvswitch: release vport resources on failure

[Aaron Conole <aconole@redhat.com>]

A recent commit introducing upcall packet accounting failed to properly
release the vport object when the per-cpu stats struct couldn't be
allocated.  This can cause dangling pointers to dp objects long after
they've been released.

Cc: Eelco Chaudron <echaudro@redhat.com>
Cc: wangchuanlei <wangchuanlei@inspur.com>
Fixes: 1933ea365aa7 ("net: openvswitch: Add support to count upcall packets")
Reported-by: syzbot+8f4e2dcfcb3209ac35f9@syzkaller.appspotmail.com
Signed-off-by: Aaron Conole <aconole@redhat.com>
---
 net/openvswitch/datapath.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/net/openvswitch/datapath.c b/net/openvswitch/datapath.c
index 932bcf766d63..6774baf9e212 100644
--- a/net/openvswitch/datapath.c
+++ b/net/openvswitch/datapath.c
@@ -1854,7 +1854,7 @@ static int ovs_dp_cmd_new(struct sk_buff *skb, struct genl_info *info)
 	vport->upcall_stats = netdev_alloc_pcpu_stats(struct vport_upcall_stats_percpu);
 	if (!vport->upcall_stats) {
 		err = -ENOMEM;
-		goto err_destroy_portids;
+		goto err_destroy_vport;
 	}
 
 	err = ovs_dp_cmd_fill_info(dp, reply, info->snd_portid,
@@ -1869,6 +1869,8 @@ static int ovs_dp_cmd_new(struct sk_buff *skb, struct genl_info *info)
 	ovs_notify(&dp_datapath_genl_family, reply, info);
 	return 0;
 
+err_destroy_vport:
+	ovs_dp_detach_port(vport);
 err_destroy_portids:
 	kfree(rcu_dereference_raw(dp->upcall_portids));
 err_unlock_and_destroy_meters:
@@ -2316,7 +2318,7 @@ static int ovs_vport_cmd_new(struct sk_buff *skb, struct genl_info *info)
 	vport->upcall_stats = netdev_alloc_pcpu_stats(struct vport_upcall_stats_percpu);
 	if (!vport->upcall_stats) {
 		err = -ENOMEM;
-		goto exit_unlock_free;
+		goto exit_unlock_free_vport;
 	}
 
 	err = ovs_vport_cmd_fill_info(vport, reply, genl_info_net(info),
@@ -2336,6 +2338,8 @@ static int ovs_vport_cmd_new(struct sk_buff *skb, struct genl_info *info)
 	ovs_notify(&dp_vport_genl_family, reply, info);
 	return 0;
 
+exit_unlock_free_vport:
+	ovs_dp_detach_port(vport);
 exit_unlock_free:
 	ovs_unlock();
 	kfree_skb(reply);
-- 
2.31.1