ibmvnic: check failover_pending in login response

commit 273c29e upstream.

If a failover occurs before a login response is received, the login
response buffer maybe undefined. Check that there was no failover
before accessing the login response buffer.

Fixes: 032c5e8 ("Driver for IBM System i/p VNIC protocol")
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/net/ethernet/ibm/ibmvnic.c

@@ -4700,6 +4700,14 @@ static int handle_login_rsp(union ibmvnic_crq *login_rsp_crq,
 		return 0;
 	}
 
+	if (adapter->failover_pending) {
+		adapter->init_done_rc = -EAGAIN;
+		netdev_dbg(netdev, "Failover pending, ignoring login response\n");
+		complete(&adapter->init_done);
+		/* login response buffer will be released on reset */
+		return 0;
+	}
+
 	netdev->mtu = adapter->req_mtu - ETH_HLEN;
 
 	netdev_dbg(adapter->netdev, "Login Response Buffer:\n");