gpio: pxa: Fix potential NULL dereference

[ Upstream commit 9506755633d0b32ef76f67c345000178e9b0dfc4 ]

platform_get_resource() may fail and return NULL, so we should
better check it's return value to avoid a NULL pointer dereference
a bit later in the code.

This is detected by Coccinelle semantic patch.

@@
expression pdev, res, n, t, e, e1, e2;
@@

res = platform_get_resource(pdev, t, n);
+ if (!res)
+   return -EINVAL;
... when != res == NULL
e = devm_ioremap(e1, res->start, e2);

Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Acked-by: Robert Jarzmik <robert.jarzmik@free.fr>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/gpio/gpio-pxa.c b/drivers/gpio/gpio-pxa.c
index 6029899..2943dfc 100644 (file)
--- a/drivers/gpio/gpio-pxa.c
+++ b/drivers/gpio/gpio-pxa.c
@@ -662,6 +662,8 @@ static int pxa_gpio_probe(struct platform_device *pdev)
        pchip->irq0 = irq0;
        pchip->irq1 = irq1;
        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+       if (!res)
+               return -EINVAL;
        gpio_reg_base = devm_ioremap(&pdev->dev, res->start,
                                     resource_size(res));
        if (!gpio_reg_base)