ixgbe: fix bounds checking in ixgbe_setup_tc for 82598

This patch resolves an issue where users were not able to dynamically
set number of queues for 82598 via ethtool -L

Reported-by: Tal Abudi <talabudi@gmail.com>
Signed-off-by: Emil Tantilov <emil.s.tantilov@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
index afdc7fb39b2c1615db679ab0fe0af1f7a4a8485e..0853cf0f5861d136d364061566530f25258dd9c6 100644 (file)
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
@@ -7848,9 +7848,10 @@ int ixgbe_setup_tc(struct net_device *dev, u8 tc)
        bool pools;
 
        /* Hardware supports up to 8 traffic classes */
-       if (tc > adapter->dcb_cfg.num_tcs.pg_tcs ||
-           (hw->mac.type == ixgbe_mac_82598EB &&
-            tc < MAX_TRAFFIC_CLASS))
+       if (tc > adapter->dcb_cfg.num_tcs.pg_tcs)
+               return -EINVAL;
+
+       if (hw->mac.type == ixgbe_mac_82598EB && tc && tc < MAX_TRAFFIC_CLASS)
                return -EINVAL;
 
        pools = (find_first_zero_bit(&adapter->fwd_bitmask, 32) > 1);