[PATCH] net: axienet: fix a potential double free in axienet_probe()

[Wen Yang]

There is a possible use-after-free issue in the axienet_probe():

1701:   np = of_parse_phandle(pdev->dev.of_node, "axistream-connected", 0);
1702:   if (np) {
...
1787:           of_node_put(np); ---> released here
1788:           lp->eth_irq = platform_get_irq(pdev, 0);
1789:   } else {
...
1801:   }
1802:   if (IS_ERR(lp->dma_regs)) {
...
1805:           of_node_put(np); ---> double released here
1806:           goto free_netdev;
1807:   }

We solve this problem by removing the unnecessary of_node_put().

Fixes: 28ef9ebdb64c ("net: axienet: make use of axistream-connected attribute 
optional")
Signed-off-by: Wen Yang <wen.yan...@zte.com.cn>
Cc: Anirudha Sarangi <anir...@xilinx.com>
Cc: John Linn <john.l...@xilinx.com>
Cc: "David S. Miller" <da...@davemloft.net>
Cc: Michal Simek <michal.si...@xilinx.com>
Cc: Robert Hancock <hanc...@sedsystems.ca>
Cc: net...@vger.kernel.org
Cc: linux-arm-ker...@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
---
 drivers/net/ethernet/xilinx/xilinx_axienet_main.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/drivers/net/ethernet/xilinx/xilinx_axienet_main.c 
b/drivers/net/ethernet/xilinx/xilinx_axienet_main.c
index 561e28a..4fc627f 100644
--- a/drivers/net/ethernet/xilinx/xilinx_axienet_main.c
+++ b/drivers/net/ethernet/xilinx/xilinx_axienet_main.c
@@ -1802,7 +1802,6 @@ static int axienet_probe(struct platform_device *pdev)
        if (IS_ERR(lp->dma_regs)) {
                dev_err(&pdev->dev, "could not map DMA regs\n");
                ret = PTR_ERR(lp->dma_regs);
-               of_node_put(np);
                goto free_netdev;
        }
        if ((lp->rx_irq <= 0) || (lp->tx_irq <= 0)) {
-- 
2.9.5