gpio: Remove VLA from stmpe driver
The new challenge is to remove VLAs from the kernel
(see https://lkml.org/lkml/2018/3/7/621)
The number of GPIOs on the supported chips is fairly small
so stack allocate to a known upper bound and spit out a warning
if any new chips have more gpios.
Signed-off-by: Laura Abbott <labbott@redhat.com>
Reviewed-by: Phil Reid <preid@electromag.com.au>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
diff --git a/drivers/gpio/gpio-stmpe.c b/drivers/gpio/gpio-stmpe.c
index f8d7d1c..8d6a5a7 100644
--- a/drivers/gpio/gpio-stmpe.c
+++ b/drivers/gpio/gpio-stmpe.c
@@ -363,13 +363,15 @@ static struct irq_chip stmpe_gpio_irq_chip = {
.irq_set_type = stmpe_gpio_irq_set_type,
};
+#define MAX_GPIOS 24
+
static irqreturn_t stmpe_gpio_irq(int irq, void *dev)
{
struct stmpe_gpio *stmpe_gpio = dev;
struct stmpe *stmpe = stmpe_gpio->stmpe;
u8 statmsbreg;
int num_banks = DIV_ROUND_UP(stmpe->num_gpios, 8);
- u8 status[num_banks];
+ u8 status[DIV_ROUND_UP(MAX_GPIOS, 8)];
int ret;
int i;
@@ -434,6 +436,11 @@ static int stmpe_gpio_probe(struct platform_device *pdev)
struct stmpe_gpio *stmpe_gpio;
int ret, irq;
+ if (stmpe->num_gpios > MAX_GPIOS) {
+ dev_err(&pdev->dev, "Need to increase maximum GPIO number\n");
+ return -EINVAL;
+ }
+
stmpe_gpio = kzalloc(sizeof(*stmpe_gpio), GFP_KERNEL);
if (!stmpe_gpio)
return -ENOMEM;