mtd: rawnand: jz4780: fix possible object reference leak

of_find_device_by_node() takes a reference to the struct device
when it finds a match via get_device, there is no need to call
get_device() twice.
We also should make sure to drop the reference to the device
taken by of_find_device_by_node() on driver unbind.

Fixes: ae02ab00aa3c ("mtd: nand: jz4780: driver for NAND devices on JZ4780 SoCs")
Signed-off-by: Wen Yang <yellowriver2010@hotmail.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

diff --git a/drivers/mtd/nand/raw/jz4780_bch.c b/drivers/mtd/nand/raw/jz4780_bch.c
index 7201827809e9aa461b5662a17f0e297c7379997d..c5f74ed85862679e1ea6b6cdc15b95d45e11b2ec 100644 (file)
--- a/drivers/mtd/nand/raw/jz4780_bch.c
+++ b/drivers/mtd/nand/raw/jz4780_bch.c
@@ -281,12 +281,15 @@ static struct jz4780_bch *jz4780_bch_get(struct device_node *np)
        struct jz4780_bch *bch;
 
        pdev = of_find_device_by_node(np);
-       if (!pdev || !platform_get_drvdata(pdev))
+       if (!pdev)
                return ERR_PTR(-EPROBE_DEFER);
 
-       get_device(&pdev->dev);
-
        bch = platform_get_drvdata(pdev);
+       if (!bch) {
+               put_device(&pdev->dev);
+               return ERR_PTR(-EPROBE_DEFER);
+       }
+
        clk_prepare_enable(bch->clk);
 
        return bch;