[PATCH 7/7] net: sxgbe: manage IRQ data lifetimes with devres

[Jiale Yao]

sxgbe_drv_remove() frees the netdev and hardware operations while
managed IRQs remain registered until the remove callback returns. The
handlers dereference these objects, so an interrupt in that window can
access freed memory.

Allocate both objects with devres. They are acquired before the IRQs and
are consequently released only after the IRQ resources have been
removed.

Fixes: 1edb9ca69e8a ("net: sxgbe: add basic framework for Samsung 10Gb ethernet driver")

Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Jiale Yao <yaojiale02@xxxxxxx>
---
 .../net/ethernet/samsung/sxgbe/sxgbe_main.c   | 26 +++++++------------
 1 file changed, 9 insertions(+), 17 deletions(-)

diff --git a/drivers/net/ethernet/samsung/sxgbe/sxgbe_main.c b/drivers/net/ethernet/samsung/sxgbe/sxgbe_main.c
index 70cf3619555f..ada851477302 100644
--- a/drivers/net/ethernet/samsung/sxgbe/sxgbe_main.c
+++ b/drivers/net/ethernet/samsung/sxgbe/sxgbe_main.c
@@ -2007,7 +2007,7 @@ static int sxgbe_hw_init(struct sxgbe_priv_data * const priv)
 {
 	u32 ctrl_ids;
 
-	priv->hw = kmalloc_obj(*priv->hw);
+	priv->hw = devm_kmalloc(priv->device, sizeof(*priv->hw), GFP_KERNEL);
 	if(!priv->hw)
 		return -ENOMEM;
 
@@ -2058,7 +2058,7 @@ static int sxgbe_sw_reset(void __iomem *addr)
  * @plat_dat: platform data pointer
  * @addr: iobase memory address
  * Description: this is the main probe function used to
- * call the alloc_etherdev, allocate the priv structure.
+ * allocate the netdev and priv structure.
  */
 struct sxgbe_priv_data *sxgbe_drv_probe(struct device *device,
 					struct sxgbe_plat_data *plat_dat,
@@ -2069,8 +2069,8 @@ struct sxgbe_priv_data *sxgbe_drv_probe(struct device *device,
 	int ret;
 	u8 queue_num;
 
-	ndev = alloc_etherdev_mqs(sizeof(struct sxgbe_priv_data),
-				  SXGBE_TX_QUEUES, SXGBE_RX_QUEUES);
+	ndev = devm_alloc_etherdev_mqs(device, sizeof(struct sxgbe_priv_data),
+				       SXGBE_TX_QUEUES, SXGBE_RX_QUEUES);
 	if (!ndev)
 		return NULL;
 
@@ -2086,7 +2086,7 @@ struct sxgbe_priv_data *sxgbe_drv_probe(struct device *device,
 
 	ret = sxgbe_sw_reset(priv->ioaddr);
 	if (ret)
-		goto error_free_netdev;
+		goto error_return;
 
 	/* Verify driver arguments */
 	sxgbe_verify_args();
@@ -2094,16 +2094,16 @@ struct sxgbe_priv_data *sxgbe_drv_probe(struct device *device,
 	/* Init MAC and get the capabilities */
 	ret = sxgbe_hw_init(priv);
 	if (ret)
-		goto error_free_netdev;
+		goto error_return;
 
 	/* allocate memory resources for Descriptor rings */
 	ret = txring_mem_alloc(priv);
 	if (ret)
-		goto error_free_hw;
+		goto error_return;
 
 	ret = rxring_mem_alloc(priv);
 	if (ret)
-		goto error_free_hw;
+		goto error_return;
 
 	ndev->netdev_ops = &sxgbe_netdev_ops;
 
@@ -2191,11 +2191,7 @@ struct sxgbe_priv_data *sxgbe_drv_probe(struct device *device,
 	clk_put(priv->sxgbe_clk);
 error_napi_del:
 	netif_napi_del(&priv->napi);
-error_free_hw:
-	kfree(priv->hw);
-error_free_netdev:
-	free_netdev(ndev);
-
+error_return:
 	return NULL;
 }
 
@@ -2229,10 +2225,6 @@ void sxgbe_drv_remove(struct net_device *ndev)
 	clk_put(priv->sxgbe_clk);
 
 	netif_napi_del(&priv->napi);
-
-	kfree(priv->hw);
-
-	free_netdev(ndev);
 }
 
 #ifdef CONFIG_PM
-- 
2.34.1