[PATCH 4.9 117/138] gpio: mockup: dynamically allocate memory for chip name

[Greg Kroah-Hartman]

4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Bartosz Golaszewski <bgolaszewski@xxxxxxxxxxxx>


[ Upstream commit ad6d8004fa29a8958381b60215e32d1e903b0492 ]

Currently the chip name buffer is allocated on the stack and the
address of the buffer is passed to the gpio framework. It's invalid
after probe() returns, so the sysfs label attribute displays garbage.

Use devm_kasprintf() for each string instead.

Signed-off-by: Bartosz Golaszewski <bgolaszewski@xxxxxxxxxxxx>
Signed-off-by: Linus Walleij <linus.walleij@xxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 drivers/gpio/gpio-mockup.c |   10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

--- a/drivers/gpio/gpio-mockup.c
+++ b/drivers/gpio/gpio-mockup.c
@@ -126,7 +126,7 @@ static int mockup_gpio_probe(struct plat
 	int i;
 	int base;
 	int ngpio;
-	char chip_name[sizeof(GPIO_NAME) + 3];
+	char *chip_name;
 
 	if (gpio_mockup_params_nr < 2)
 		return -EINVAL;
@@ -146,8 +146,12 @@ static int mockup_gpio_probe(struct plat
 			ngpio = gpio_mockup_ranges[i * 2 + 1] - base;
 
 		if (ngpio >= 0) {
-			sprintf(chip_name, "%s-%c", GPIO_NAME,
-				pins_name_start + i);
+			chip_name = devm_kasprintf(dev, GFP_KERNEL,
+						   "%s-%c", GPIO_NAME,
+						   pins_name_start + i);
+			if (!chip_name)
+				return -ENOMEM;
+
 			ret = mockup_gpio_add(dev, &cntr[i],
 					      chip_name, base, ngpio);
 		} else {