From ecfb6ce5c09ce1fbfde39418123d4fc8ab4b7985 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 commit 54d77198fdfbc4f0fe11b4252c1d9c97d51a3264 upstream. 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: 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 Signed-off-by: Greg Kroah-Hartman --- 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 b747c76fd2b1f..0db320ea0286e 100644 --- a/drivers/gpio/gpiolib.c +++ b/drivers/gpio/gpiolib.c @@ -1339,10 +1339,13 @@ done: /* * 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; \ } \ @@ -1353,7 +1356,9 @@ done: } } 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; \ } \ -- 2.47.2