ixgbe: Fix potential memory leak/driver panic issue while setting up Tx & Rx ring parameters

While setting up the ring parameters using ethtool the driver can
panic or leak memory as ixgbe_open tries to setup tx & rx resources.
The updated logic will use ixgbe_down/up after successful allocation of
tx & rx resources

Signed-off-by: Mallikarjuna R Chilakala <mallikarjuna.chilakala@intel.com>
Signed-off-by: Peter P Waskiewicz Jr <peter.p.waskiewicz.jr@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
CC: stable@kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 58 insertions, 43 deletions

diff --git a/drivers/net/ixgbe/ixgbe_ethtool.c b/drivers/net/ixgbe/ixgbe_ethtool.c
index 55970ec72de3..aafc120f164e 100644
--- a/drivers/net/ixgbe/ixgbe_ethtool.c
+++ b/drivers/net/ixgbe/ixgbe_ethtool.c
@@ -734,9 +734,10 @@ static int ixgbe_set_ringparam(struct net_device *netdev,
                                struct ethtool_ringparam *ring)
 {
         struct ixgbe_adapter *adapter = netdev_priv(netdev);
-        struct ixgbe_ring *temp_ring;
+        struct ixgbe_ring *temp_tx_ring, *temp_rx_ring;
         int i, err;
         u32 new_rx_count, new_tx_count;
+        bool need_update = false;
 
         if ((ring->rx_mini_pending) || (ring->rx_jumbo_pending))
                 return -EINVAL;
@@ -755,80 +756,94 @@ static int ixgbe_set_ringparam(struct net_device *netdev,
                 return 0;
         }
 
-        temp_ring = kcalloc(adapter->num_tx_queues,
-                            sizeof(struct ixgbe_ring), GFP_KERNEL);
-        if (!temp_ring)
-                return -ENOMEM;
-
         while (test_and_set_bit(__IXGBE_RESETTING, &adapter->state))
                 msleep(1);
 
-        if (new_tx_count != adapter->tx_ring->count) {
+        temp_tx_ring = kcalloc(adapter->num_tx_queues,
+                               sizeof(struct ixgbe_ring), GFP_KERNEL);
+        if (!temp_tx_ring) {
+                err = -ENOMEM;
+                goto err_setup;
+        }
+
+        if (new_tx_count != adapter->tx_ring_count) {
+                memcpy(temp_tx_ring, adapter->tx_ring,
+                       adapter->num_tx_queues * sizeof(struct ixgbe_ring));
                 for (i = 0; i < adapter->num_tx_queues; i++) {
-                        temp_ring[i].count = new_tx_count;
-                        err = ixgbe_setup_tx_resources(adapter, &temp_ring[i]);
+                        temp_tx_ring[i].count = new_tx_count;
+                        err = ixgbe_setup_tx_resources(adapter,
+                                                       &temp_tx_ring[i]);
                         if (err) {
                                 while (i) {
                                         i--;
                                         ixgbe_free_tx_resources(adapter,
-                                                                &temp_ring[i]);
+                                                                &temp_tx_ring[i]);
                                 }
                                 goto err_setup;
                         }
-                        temp_ring[i].v_idx = adapter->tx_ring[i].v_idx;
+                        temp_tx_ring[i].v_idx = adapter->tx_ring[i].v_idx;
                 }
-                if (netif_running(netdev))
-                        netdev->netdev_ops->ndo_stop(netdev);
-                ixgbe_reset_interrupt_capability(adapter);
-                ixgbe_napi_del_all(adapter);
-                INIT_LIST_HEAD(&netdev->napi_list);
-                kfree(adapter->tx_ring);
-                adapter->tx_ring = temp_ring;
-                temp_ring = NULL;
-                adapter->tx_ring_count = new_tx_count;
+                need_update = true;
         }
 
-        temp_ring = kcalloc(adapter->num_rx_queues,
-                            sizeof(struct ixgbe_ring), GFP_KERNEL);
-        if (!temp_ring) {
-                if (netif_running(netdev))
-                        netdev->netdev_ops->ndo_open(netdev);
-                return -ENOMEM;
+        temp_rx_ring = kcalloc(adapter->num_rx_queues,
+                               sizeof(struct ixgbe_ring), GFP_KERNEL);
+        if ((!temp_rx_ring) && (need_update)) {
+                for (i = 0; i < adapter->num_tx_queues; i++)
+                        ixgbe_free_tx_resources(adapter, &temp_tx_ring[i]);
+                kfree(temp_tx_ring);
+                err = -ENOMEM;
+                goto err_setup;
         }
 
-        if (new_rx_count != adapter->rx_ring->count) {
+        if (new_rx_count != adapter->rx_ring_count) {
+                memcpy(temp_rx_ring, adapter->rx_ring,
+                       adapter->num_rx_queues * sizeof(struct ixgbe_ring));
                 for (i = 0; i < adapter->num_rx_queues; i++) {
-                        temp_ring[i].count = new_rx_count;
-                        err = ixgbe_setup_rx_resources(adapter, &temp_ring[i]);
+                        temp_rx_ring[i].count = new_rx_count;
+                        err = ixgbe_setup_rx_resources(adapter,
+                                                       &temp_rx_ring[i]);
                         if (err) {
                                 while (i) {
                                         i--;
                                         ixgbe_free_rx_resources(adapter,
-                                                                &temp_ring[i]);
+                                                              &temp_rx_ring[i]);
                                 }
                                 goto err_setup;
                         }
-                        temp_ring[i].v_idx = adapter->rx_ring[i].v_idx;
+                        temp_rx_ring[i].v_idx = adapter->rx_ring[i].v_idx;
                 }
+                need_update = true;
+        }
+
+        /* if rings need to be updated, here's the place to do it in one shot */
+        if (need_update) {
                 if (netif_running(netdev))
-                        netdev->netdev_ops->ndo_stop(netdev);
-                ixgbe_reset_interrupt_capability(adapter);
-                ixgbe_napi_del_all(adapter);
-                INIT_LIST_HEAD(&netdev->napi_list);
-                kfree(adapter->rx_ring);
-                adapter->rx_ring = temp_ring;
-                temp_ring = NULL;
-
-                adapter->rx_ring_count = new_rx_count;
+                        ixgbe_down(adapter);
+
+                /* tx */
+                if (new_tx_count != adapter->tx_ring_count) {
+                        kfree(adapter->tx_ring);
+                        adapter->tx_ring = temp_tx_ring;
+                        temp_tx_ring = NULL;
+                        adapter->tx_ring_count = new_tx_count;
+                }
+
+                /* rx */
+                if (new_rx_count != adapter->rx_ring_count) {
+                        kfree(adapter->rx_ring);
+                        adapter->rx_ring = temp_rx_ring;
+                        temp_rx_ring = NULL;
+                        adapter->rx_ring_count = new_rx_count;
+                }
         }
 
         /* success! */
         err = 0;
-err_setup:
-        ixgbe_init_interrupt_scheme(adapter);
         if (netif_running(netdev))
-                netdev->netdev_ops->ndo_open(netdev);
+                ixgbe_up(adapter);
 
+err_setup:
         clear_bit(__IXGBE_RESETTING, &adapter->state);
         return err;
 }