From 54d77198fdfbc4f0fe11b4252c1d9c97d51a3264 Mon Sep 17 00:00:00 2001 From: Linus Walleij Date: Mon, 30 May 2016 16:48:39 +0200 Subject: [PATCH] gpio: bail out silently on NULL descriptors MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit In fdeb8e1547cb9dd39d5d7223b33f3565cf86c28e ("gpio: reflect base and ngpio into gpio_device") assumed that GPIO descriptors are either valid or error pointers, but gpiod_get_[index_]optional() actually return NULL descriptors and then all subsequent calls should just bail out. Cc: stable@vger.kernel.org Cc: Sergei Shtylyov Cc: Florian Fainelli Cc: Andrew Lunn Fixes: fdeb8e1547cb ("gpio: reflect base and ngpio into gpio_device") Reported-by: Uwe Kleine-König Signed-off-by: Linus Walleij --- drivers/gpio/gpiolib.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c index 68dbff5d8f57..246b6b051b0d 100644 --- a/drivers/gpio/gpiolib.c +++ b/drivers/gpio/gpiolib.c @@ -1367,10 +1367,13 @@ static int __gpiod_request(struct gpio_desc *desc, const char *label) /* * This descriptor validation needs to be inserted verbatim into each * function taking a descriptor, so we need to use a preprocessor - * macro to avoid endless duplication. + * macro to avoid endless duplication. If the desc is NULL it is an + * optional GPIO and calls should just bail out. */ #define VALIDATE_DESC(desc) do { \ - if (!desc || !desc->gdev) { \ + if (!desc) \ + return 0; \ + if (!desc->gdev) { \ pr_warn("%s: invalid GPIO\n", __func__); \ return -EINVAL; \ } \ @@ -1381,7 +1384,9 @@ static int __gpiod_request(struct gpio_desc *desc, const char *label) } } while (0) #define VALIDATE_DESC_VOID(desc) do { \ - if (!desc || !desc->gdev) { \ + if (!desc) \ + return; \ + if (!desc->gdev) { \ pr_warn("%s: invalid GPIO\n", __func__); \ return; \ } \ -- 2.45.2