net: openvswitch: fix missing checks for nla_nest_start

nla_nest_start may fail and thus deserves a check.
The fix returns -EMSGSIZE when it fails.

Signed-off-by: Kangjie Lu <kjlu@umn.edu>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/openvswitch/datapath.c b/net/openvswitch/datapath.c
index 45d1469308b048389aa503e737bccdef23f895a7..9dd158ab51b310e28354237ff3bcd101a8b829f5 100644 (file)
--- a/net/openvswitch/datapath.c
+++ b/net/openvswitch/datapath.c
@@ -464,6 +464,10 @@ static int queue_userspace_packet(struct datapath *dp, struct sk_buff *skb,
 
        if (upcall_info->egress_tun_info) {
                nla = nla_nest_start(user_skb, OVS_PACKET_ATTR_EGRESS_TUN_KEY);
+               if (!nla) {
+                       err = -EMSGSIZE;
+                       goto out;
+               }
                err = ovs_nla_put_tunnel_info(user_skb,
                                              upcall_info->egress_tun_info);
                BUG_ON(err);
@@ -472,6 +476,10 @@ static int queue_userspace_packet(struct datapath *dp, struct sk_buff *skb,
 
        if (upcall_info->actions_len) {
                nla = nla_nest_start(user_skb, OVS_PACKET_ATTR_ACTIONS);
+               if (!nla) {
+                       err = -EMSGSIZE;
+                       goto out;
+               }
                err = ovs_nla_put_actions(upcall_info->actions,
                                          upcall_info->actions_len,
                                          user_skb);