Patch "gpio: GPIO_GET_LINEHANDLE_IOCTL: Validate line offset" has been added to the 4.8-stable tree

Patch "gpio: GPIO_GET_LINEHANDLE_IOCTL: Validate line offset" has been added to the 4.8-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    gpio: GPIO_GET_LINEHANDLE_IOCTL: Validate line offset

to the 4.8-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     gpio-gpio_get_linehandle_ioctl-validate-line-offset.patch
and it can be found in the queue-4.8 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From e405f9fcb63602d35f7a419ededa3f952a395a72 Mon Sep 17 00:00:00 2001
From: Lars-Peter Clausen <lars@metafoo.de>
Date: Tue, 18 Oct 2016 16:54:01 +0200
Subject: gpio: GPIO_GET_LINEHANDLE_IOCTL: Validate line offset

From: Lars-Peter Clausen <lars@metafoo.de>

commit e405f9fcb63602d35f7a419ededa3f952a395a72 upstream.

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.

Fixes: d7c51b47ac11 ("gpio: userspace ABI for reading/writing GPIO lines")
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/gpio/gpiolib.c |    5 +++++
 1 file changed, 5 insertions(+)

--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -442,6 +442,11 @@ static int linehandle_create(struct gpio
 		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)


Patches currently in stable-queue which might be from lars@metafoo.de are

queue-4.8/gpio-gpio_get_chipinfo_ioctl-fix-line-offset-validation.patch
queue-4.8/gpio-gpio_get_line-handle-event-_ioctl-fix-file-descriptor-leak.patch
queue-4.8/gpio-gpio_get_chipinfo_ioctl-fix-information-leak.patch
queue-4.8/gpio-gpio_get_lineevent_ioctl-reject-invalid-line-and-event-flags.patch
queue-4.8/gpio-gpiohandle_get_line_values_ioctl-fix-another-information-leak.patch
queue-4.8/gpio-gpio_get_linehandle_ioctl-reject-invalid-line-flags.patch
queue-4.8/gpio-gpio_get_lineevent_ioctl-validate-line-offset.patch
queue-4.8/gpio-gpiohandle_get_line_values_ioctl-fix-information-leak.patch
queue-4.8/gpio-gpio_get_linehandle_ioctl-validate-line-offset.patch