Patch "gpio: GPIOHANDLE_GET_LINE_VALUES_IOCTL: Fix another information leak" has been added to the 4.8-stable tree

[<gregkh@linuxfoundation.org>]

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

    gpio: GPIOHANDLE_GET_LINE_VALUES_IOCTL: Fix another information leak

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-gpiohandle_get_line_values_ioctl-fix-another-information-leak.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 d82aa4a8f2e8df9673ddb099262355da4c9b99b1 Mon Sep 17 00:00:00 2001
From: Lars-Peter Clausen <lars@metafoo.de>
Date: Tue, 18 Oct 2016 16:54:04 +0200
Subject: gpio: GPIOHANDLE_GET_LINE_VALUES_IOCTL: Fix another information leak

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

commit d82aa4a8f2e8df9673ddb099262355da4c9b99b1 upstream.

The GPIOHANDLE_GET_LINE_VALUES_IOCTL handler allocates a gpiohandle_data
struct on the stack and then passes it to copy_to_user(). But only the
first element of the values array in the struct is set, which leaves the
struct partially initialized.

This exposes the previous, potentially sensitive, stack content to the
issuing userspace application. To avoid this make sure that the struct is
fully initialized.

Cc: stable@vger.kernel.org
Fixes: 61f922db7221 ("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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/gpio/gpiolib.c |    2 ++
 1 file changed, 2 insertions(+)

--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -645,6 +645,8 @@ static long lineevent_ioctl(struct file
 	if (cmd == GPIOHANDLE_GET_LINE_VALUES_IOCTL) {
 		int val;
 
+		memset(&ghd, 0, sizeof(ghd));
+
 		val = gpiod_get_value_cansleep(le->desc);
 		if (val < 0)
 			return val;


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