From mboxrd@z Thu Jan 1 00:00:00 1970 From: Moritz Fischer Subject: [PATCH 1/2] net: nixge: Fix error path for obtaining mac address Date: Fri, 4 May 2018 10:18:33 -0700 Message-ID: <20180504171834.9365-1-mdf@kernel.org> Cc: netdev@vger.kernel.org, davem@davemloft.net, alex.williams@ni.com, Moritz Fischer To: linux-kernel@vger.kernel.org Return-path: Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org 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 Signed-off-by: Moritz Fischer --- 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