From e405f9fcb63602d35f7a419ededa3f952a395a72 Mon Sep 17 00:00:00 2001 From: Lars-Peter Clausen Date: Tue, 18 Oct 2016 16:54:01 +0200 Subject: [PATCH] gpio: GPIO_GET_LINEHANDLE_IOCTL: Validate line offset The line offset that is used as an index into the descs array is provided by userspace and might go beyond the bounds of the array. If that happens undefined behavior will occur. Make sure that the offset is within the bounds of the desc array and reject any requests that specify a value outside of it. Cc: stable@vger.kernel.org Fixes: d7c51b47ac11 ("gpio: userspace ABI for reading/writing GPIO lines") Signed-off-by: Lars-Peter Clausen Signed-off-by: Linus Walleij --- drivers/gpio/gpiolib.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c index 7a01969169e8..d287cb4e97c4 100644 --- a/drivers/gpio/gpiolib.c +++ b/drivers/gpio/gpiolib.c @@ -444,6 +444,11 @@ static int linehandle_create(struct gpio_device *gdev, void __user *ip) u32 lflags = handlereq.flags; struct gpio_desc *desc; + if (offset >= gdev->ngpio) { + ret = -EINVAL; + goto out_free_descs; + } + desc = &gdev->descs[offset]; ret = gpiod_request(desc, lh->label); if (ret) -- 2.20.1