net: Fix dev_mc_add()

Commit 6e17d45a (net: add addr len check to dev_mc_add)
added a bug in dev_mc_add(), since it can now exit with a lock
imbalance.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
CC: Jiri Pirko <jpirko@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 3 insertions, 2 deletions

diff --git a/net/core/dev_mcast.c b/net/core/dev_mcast.c
index fd91569e2394..3dc295beb483 100644
--- a/net/core/dev_mcast.c
+++ b/net/core/dev_mcast.c
@@ -97,8 +97,9 @@ int dev_mc_add(struct net_device *dev, void *addr, int alen, int glbl)
 
         netif_addr_lock_bh(dev);
         if (alen != dev->addr_len)
-                return -EINVAL;
-        err = __dev_addr_add(&dev->mc_list, &dev->mc_count, addr, alen, glbl);
+                err = -EINVAL;
+        else
+                err = __dev_addr_add(&dev->mc_list, &dev->mc_count, addr, alen, glbl);
         if (!err)
                 __dev_set_rx_mode(dev);
         netif_addr_unlock_bh(dev);