[PATCH 07/20] hwmon: (lm78) check return value after calling platform_get_resource()

[Yang Yingliang]

It will cause null-ptr-deref if platform_get_resource() returns NULL,
we need check the return value.

Fixes: c40769fee13c ("hwmon/lm78: No longer use i2c-isa")
Signed-off-by: Yang Yingliang <yangyingliang@xxxxxxxxxx>
---
 drivers/hwmon/lm78.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/hwmon/lm78.c b/drivers/hwmon/lm78.c
index 5e129cbec1cb..71c2a1bc75cc 100644
--- a/drivers/hwmon/lm78.c
+++ b/drivers/hwmon/lm78.c
@@ -792,6 +792,8 @@ static int lm78_isa_probe(struct platform_device *pdev)
 
 	/* Reserve the ISA region */
 	res = platform_get_resource(pdev, IORESOURCE_IO, 0);
+	if (!res)
+		return -EINVAL;
 	if (!devm_request_region(dev, res->start + LM78_ADDR_REG_OFFSET,
 				 2, "lm78"))
 		return -EBUSY;
-- 
2.25.1