Commit b8b0e3d3 authored Oct 18, 2016 by Lars-Peter Clausen Committed by Linus Walleij Oct 21, 2016

gpio: GPIO_GET_LINEEVENT_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: 61f922db ("gpio: userspace ABI for reading GPIO line events")
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

parent d82aa4a8

drivers/gpio/gpiolib.c

+5 −0

Original line number	Diff line number	Diff line
		@@ -733,6 +733,11 @@ static int lineevent_create(struct gpio_device gdev, void __user ip)
		lflags = eventreq.handleflags;
		eflags = eventreq.eventflags;

		if (offset >= gdev->ngpio) {
		ret = -EINVAL;
		goto out_free_label;
		}

		/* This is just wrong: we don't look for events on output lines */
		if (lflags & GPIOHANDLE_REQUEST_OUTPUT) {
		ret = -EINVAL;