Commit 22ed1d47 authored Sep 09, 2019 by Kent Gibson Committed by Greg Kroah-Hartman Sep 19, 2019

gpio: fix line flag validation in linehandle_create



commit e95fbc130a162ba9ad956311b95aa0da269eea48 upstream.

linehandle_create should not allow both GPIOHANDLE_REQUEST_INPUT
and GPIOHANDLE_REQUEST_OUTPUT to be set.

Fixes: d7c51b47 ("gpio: userspace ABI for reading/writing GPIO lines")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Kent Gibson <warthog618@gmail.com>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent 705df757

drivers/gpio/gpiolib.c

+8 −0

Original line number	Diff line number	Diff line
		@@ -524,6 +524,14 @@ static int linehandle_create(struct gpio_device gdev, void __user ip)
		if (lflags & ~GPIOHANDLE_REQUEST_VALID_FLAGS)
		return -EINVAL;

		/*
		* Do not allow both INPUT & OUTPUT flags to be set as they are
		* contradictory.
		*/
		if ((lflags & GPIOHANDLE_REQUEST_INPUT) &&
		(lflags & GPIOHANDLE_REQUEST_OUTPUT))
		return -EINVAL;

		/*
		* Do not allow OPEN_SOURCE & OPEN_DRAIN flags in a single request. If
		* the hardware actually supports enabling both at the same time the