5.4-stable review patch. If anyone has any objections, please let me know.
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From: Tong Zhang ztong0001@gmail.com
[ Upstream commit 6577b9a551aedb86bca6d4438c28386361845108 ]
There are two issues when handling error case in com20020pci_probe()
1. priv might be not initialized yet when calling com20020pci_remove() from com20020pci_probe(), since the priv is set at the very last but it can jump to error handling in the middle and priv remains NULL. 2. memory leak - the net device is allocated in alloc_arcdev but not properly released if error happens in the middle of the big for loop
[ 1.529110] BUG: kernel NULL pointer dereference, address: 0000000000000008 [ 1.531447] RIP: 0010:com20020pci_remove+0x15/0x60 [com20020_pci] [ 1.536805] Call Trace: [ 1.536939] com20020pci_probe+0x3f2/0x48c [com20020_pci] [ 1.537226] local_pci_probe+0x48/0x80 [ 1.539918] com20020pci_init+0x3f/0x1000 [com20020_pci]
Signed-off-by: Tong Zhang ztong0001@gmail.com Signed-off-by: David S. Miller davem@davemloft.net Stable-dep-of: 6b17a597fc2f ("arcnet: restoring support for multiple Sohard Arcnet cards") Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/arcnet/com20020-pci.c | 34 +++++++++++++++++-------------- 1 file changed, 19 insertions(+), 15 deletions(-)
diff --git a/drivers/net/arcnet/com20020-pci.c b/drivers/net/arcnet/com20020-pci.c index b4f8798d8c509..28dccbc0e8d8f 100644 --- a/drivers/net/arcnet/com20020-pci.c +++ b/drivers/net/arcnet/com20020-pci.c @@ -127,6 +127,8 @@ static int com20020pci_probe(struct pci_dev *pdev, int i, ioaddr, ret; struct resource *r;
+ ret = 0; + if (pci_enable_device(pdev)) return -EIO;
@@ -142,6 +144,8 @@ static int com20020pci_probe(struct pci_dev *pdev, priv->ci = ci; mm = &ci->misc_map;
+ pci_set_drvdata(pdev, priv); + INIT_LIST_HEAD(&priv->list_dev);
if (mm->size) { @@ -164,7 +168,7 @@ static int com20020pci_probe(struct pci_dev *pdev, dev = alloc_arcdev(device); if (!dev) { ret = -ENOMEM; - goto out_port; + break; } dev->dev_port = i;
@@ -181,7 +185,7 @@ static int com20020pci_probe(struct pci_dev *pdev, pr_err("IO region %xh-%xh already allocated\n", ioaddr, ioaddr + cm->size - 1); ret = -EBUSY; - goto out_port; + goto err_free_arcdev; }
/* Dummy access after Reset @@ -219,18 +223,18 @@ static int com20020pci_probe(struct pci_dev *pdev, if (arcnet_inb(ioaddr, COM20020_REG_R_STATUS) == 0xFF) { pr_err("IO address %Xh is empty!\n", ioaddr); ret = -EIO; - goto out_port; + goto err_free_arcdev; } if (com20020_check(dev)) { ret = -EIO; - goto out_port; + goto err_free_arcdev; }
card = devm_kzalloc(&pdev->dev, sizeof(struct com20020_dev), GFP_KERNEL); if (!card) { ret = -ENOMEM; - goto out_port; + goto err_free_arcdev; }
card->index = i; @@ -256,29 +260,29 @@ static int com20020pci_probe(struct pci_dev *pdev,
ret = devm_led_classdev_register(&pdev->dev, &card->tx_led); if (ret) - goto out_port; + goto err_free_arcdev;
ret = devm_led_classdev_register(&pdev->dev, &card->recon_led); if (ret) - goto out_port; + goto err_free_arcdev;
dev_set_drvdata(&dev->dev, card);
ret = com20020_found(dev, IRQF_SHARED); if (ret) - goto out_port; + goto err_free_arcdev;
devm_arcnet_led_init(dev, dev->dev_id, i);
list_add(&card->list, &priv->list_dev); - } + continue;
- pci_set_drvdata(pdev, priv); - - return 0; - -out_port: - com20020pci_remove(pdev); +err_free_arcdev: + free_arcdev(dev); + break; + } + if (ret) + com20020pci_remove(pdev); return ret; }