[NET-NEXT PATCH 3/3] ixgbe: Fix set_ringparam in ixgbe to use the same memory pools.

[Jeff Kirsher <jeffrey.t.kirsher@intel.com>]

From: Peter P Waskiewicz Jr <peter.p.waskiewicz.jr@intel.com>

The adapter rings are kcalloc()'d, but in set_ringparam() in ixgbe_ethtool,
we replace that memory from the vmalloc() pool.  This can result in a NULL
pointer reference when trying to modify the rings at a later time, or on
device removal.

Signed-off-by: Peter P Waskiewicz Jr <peter.p.waskiewicz.jr@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
---

 drivers/net/ixgbe/ixgbe_ethtool.c |   64 +++++++++++++++++--------------------
 1 files changed, 30 insertions(+), 34 deletions(-)

diff --git a/drivers/net/ixgbe/ixgbe_ethtool.c b/drivers/net/ixgbe/ixgbe_ethtool.c
index 849c1fe..67f87a7 100644
--- a/drivers/net/ixgbe/ixgbe_ethtool.c
+++ b/drivers/net/ixgbe/ixgbe_ethtool.c
@@ -712,30 +712,15 @@ static int ixgbe_set_ringparam(struct net_device *netdev,
 		return 0;
 	}
 
-	if (adapter->num_tx_queues > adapter->num_rx_queues)
-		temp_ring = vmalloc(adapter->num_tx_queues *
-		                    sizeof(struct ixgbe_ring));
-	else
-		temp_ring = vmalloc(adapter->num_rx_queues *
-		                    sizeof(struct ixgbe_ring));
+	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 (netif_running(netdev))
-		ixgbe_down(adapter);
-
-	/*
-	 * We can't just free everything and then setup again,
-	 * because the ISRs in MSI-X mode get passed pointers
-	 * to the tx and rx ring structs.
-	 */
 	if (new_tx_count != adapter->tx_ring->count) {
-		memcpy(temp_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]);
@@ -747,21 +732,28 @@ static int ixgbe_set_ringparam(struct net_device *netdev,
 				}
 				goto err_setup;
 			}
+			temp_ring[i].v_idx = adapter->tx_ring[i].v_idx;
 		}
-
-		for (i = 0; i < adapter->num_tx_queues; i++)
-			ixgbe_free_tx_resources(adapter, &adapter->tx_ring[i]);
-
-		memcpy(adapter->tx_ring, temp_ring,
-		       adapter->num_tx_queues * sizeof(struct ixgbe_ring));
-
+		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;
 	}
 
-	if (new_rx_count != adapter->rx_ring->count) {
-		memcpy(temp_ring, adapter->rx_ring,
-		       adapter->num_rx_queues * sizeof(struct ixgbe_ring));
+	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;
+	}
 
+	if (new_rx_count != adapter->rx_ring->count) {
 		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]);
@@ -773,13 +765,16 @@ static int ixgbe_set_ringparam(struct net_device *netdev,
 				}
 				goto err_setup;
 			}
+			temp_ring[i].v_idx = adapter->rx_ring[i].v_idx;
 		}
-
-		for (i = 0; i < adapter->num_rx_queues; i++)
-			ixgbe_free_rx_resources(adapter, &adapter->rx_ring[i]);
-
-		memcpy(adapter->rx_ring, temp_ring,
-		       adapter->num_rx_queues * sizeof(struct ixgbe_ring));
+		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;
 	}
@@ -787,8 +782,9 @@ static int ixgbe_set_ringparam(struct net_device *netdev,
 	/* success! */
 	err = 0;
 err_setup:
+	ixgbe_init_interrupt_scheme(adapter);
 	if (netif_running(netdev))
-		ixgbe_up(adapter);
+		netdev->netdev_ops->ndo_open(netdev);
 
 	clear_bit(__IXGBE_RESETTING, &adapter->state);
 	return err;