bridge: mcast: Fix incomplete MDB dump

Each MDB entry is encoded in a nested netlink attribute called
'MDBA_MDB_ENTRY'. In turn, this attribute contains another nested
attributed called 'MDBA_MDB_ENTRY_INFO', which encodes a single port
group entry within the MDB entry.

The cited commit added the ability to restart a dump from a specific
port group entry. However, on failure to add a port group entry to the
dump the entire MDB entry (stored in 'nest2') is removed, resulting in
missing port group entries.

Fix this by finalizing the MDB entry with the partial list of already
encoded port group entries.

Fixes: 5205e919c9f0 ("net: bridge: mcast: add support for src list and filter mode dumping")
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Acked-by: Nikolay Aleksandrov <nikolay@nvidia.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/bridge/br_mdb.c b/net/bridge/br_mdb.c
index 67e0976aeed2b5cb41c95751590602d5c2356480..00f1651a6aba31b756d5d8c59ada1bb9d64768c7 100644 (file)
--- a/net/bridge/br_mdb.c
+++ b/net/bridge/br_mdb.c
@@ -243,7 +243,7 @@ static int br_mdb_fill_info(struct sk_buff *skb, struct netlink_callback *cb,
 
                        err = __mdb_fill_info(skb, mp, p);
                        if (err) {
-                               nla_nest_cancel(skb, nest2);
+                               nla_nest_end(skb, nest2);
                                goto out;
                        }
 skip_pg: