[PATCH net-next] bridge: tunnel: fix attribute checks in br_parse_vlan_tunnel_info

[Nikolay Aleksandrov]

These checks should go after the attributes have been parsed otherwise
we're using tb uninitialized.

Fixes: efa5356b0d97 ("bridge: per vlan dst_metadata netlink support")
Reported-by: Colin Ian King <colin.k...@canonical.com>
Signed-off-by: Nikolay Aleksandrov <niko...@cumulusnetworks.com>
---
 net/bridge/br_netlink_tunnel.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/net/bridge/br_netlink_tunnel.c b/net/bridge/br_netlink_tunnel.c
index 99c68012c9d4..62eaf750bd9e 100644
--- a/net/bridge/br_netlink_tunnel.c
+++ b/net/bridge/br_netlink_tunnel.c
@@ -229,15 +229,15 @@ int br_parse_vlan_tunnel_info(struct nlattr *attr,
 
        memset(tinfo, 0, sizeof(*tinfo));
 
-       if (!tb[IFLA_BRIDGE_VLAN_TUNNEL_ID] ||
-           !tb[IFLA_BRIDGE_VLAN_TUNNEL_VID])
-               return -EINVAL;
-
        err = nla_parse_nested(tb, IFLA_BRIDGE_VLAN_TUNNEL_MAX,
                               attr, vlan_tunnel_policy);
        if (err < 0)
                return err;
 
+       if (!tb[IFLA_BRIDGE_VLAN_TUNNEL_ID] ||
+           !tb[IFLA_BRIDGE_VLAN_TUNNEL_VID])
+               return -EINVAL;
+
        tun_id = nla_get_u32(tb[IFLA_BRIDGE_VLAN_TUNNEL_ID]);
        vid = nla_get_u16(tb[IFLA_BRIDGE_VLAN_TUNNEL_VID]);
        if (vid >= VLAN_VID_MASK)
-- 
2.1.4