From 97fe7bef56e60ef6efa186348908b954a236b2fb Mon Sep 17 00:00:00 2001 From: Laura Abbott Date: Wed, 28 Mar 2018 10:59:57 -0700 Subject: [PATCH] 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 Reviewed-by: Phil Reid Reviewed-by: Kees Cook Signed-off-by: Linus Walleij --- drivers/gpio/gpio-stmpe.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/drivers/gpio/gpio-stmpe.c b/drivers/gpio/gpio-stmpe.c index f8d7d1cd8488..8d6a5a7e612d 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;