[PATCH AUTOSEL 4.9 20/34] gpio: pxa: Fix potential NULL dereference

Sasha Levin
2018-09-15T01:34:47Z

From: Wei Yongjun <weiyongjun1@huawei.com>

[ 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>
---
drivers/gpio/gpio-pxa.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/drivers/gpio/gpio-pxa.c b/drivers/gpio/gpio-pxa.c
index 76ac906b4d78..7a6305884f97 100644
--- a/drivers/gpio/gpio-pxa.c
+++ b/drivers/gpio/gpio-pxa.c
@@ -660,6 +660,8 @@ 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)
--
2.17.1