Revamp last change. IFF_UP only required when allocating callback, not freeing.

net/devif/devif_callback.c

@@ -124,13 +124,19 @@ FAR struct devif_callback_s *
       
       if (dev)
         {
-          /* Verify that the device is valid */
+          /* Verify that the device pointer is valid, i.e., that it still
+           * points to a registered network device and also that the network
+           * device in in the UP state.
+           *
+           * And if it does, should that device also not be in the UP state?
+           */
 
-          if (!netdev_verify(dev))
+          if (!netdev_verify(dev) && (dev->d_flags & IFF_UP) != 0)
             {
               /* No.. release the callback structure and fail */
 
               devif_callback_free(NULL, NULL, list);
+              net_unlock(save);
               return NULL;
             }
 

net/netdev/netdev_verify.c

@@ -74,9 +74,9 @@ bool netdev_verify(FAR struct net_driver_s *dev)
 
       if (chkdev == dev)
         {
-          /* Yes.. return true if the interface is in the UP state */
+          /* Yes.. return true  */
 
-          valid = ((dev->d_flags & IFF_UP) != 0);
+          valid = true;
           break;
         }
     }

net/tcp/tcp_send_buffered.c

@@ -956,7 +956,6 @@ ssize_t psock_tcp_send(FAR struct socket *psock, FAR const void *buf,
     }
 #endif /* CONFIG_NET_ARP_SEND */
 
-
 #ifdef CONFIG_NET_ICMPv6_NEIGHBOR
 #ifdef CONFIG_NET_ARP_SEND
   else