[PATCH 1/2] net: nixge: Fix error path for obtaining mac address
From: Moritz Fischer
Date: Fri May 04 2018 - 13:25:43 EST
Fix issue where nixge_get_nvmem_address() returns a non-NULL
return value on a failed nvmem_cell_get() that causes an invalid
access when error value encoded in pointer is dereferenced.
Furthermore ensure that buffer allocated by nvmem_cell_read()
actually gets kfreed() if the function succeeds.
Fixes commit 492caffa8a1a ("net: ethernet: nixge: Add support for
National Instruments XGE netdev")
Reported-by: Alex Williams <alex.williams@xxxxxx>
Signed-off-by: Moritz Fischer <mdf@xxxxxxxxxx>
---
drivers/net/ethernet/ni/nixge.c | 8 +++++---
1 file changed, 5 insertions(+), 3 deletions(-)
diff --git a/drivers/net/ethernet/ni/nixge.c b/drivers/net/ethernet/ni/nixge.c
index 27364b7572fc..c41fea9253e3 100644
--- a/drivers/net/ethernet/ni/nixge.c
+++ b/drivers/net/ethernet/ni/nixge.c
@@ -1170,7 +1170,7 @@ static void *nixge_get_nvmem_address(struct device *dev)
cell = nvmem_cell_get(dev, "address");
if (IS_ERR(cell))
- return cell;
+ return NULL;
mac = nvmem_cell_read(cell, &cell_size);
nvmem_cell_put(cell);
@@ -1202,10 +1202,12 @@ static int nixge_probe(struct platform_device *pdev)
ndev->max_mtu = NIXGE_JUMBO_MTU;
mac_addr = nixge_get_nvmem_address(&pdev->dev);
- if (mac_addr && is_valid_ether_addr(mac_addr))
+ if (mac_addr && is_valid_ether_addr(mac_addr)) {
ether_addr_copy(ndev->dev_addr, mac_addr);
- else
+ kfree(mac_addr);
+ } else {
eth_hw_addr_random(ndev);
+ }
priv = netdev_priv(ndev);
priv->ndev = ndev;
--
2.17.0