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

    gpio: sysfs: fix gpio device-attribute leak

to the 3.18-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-sysfs-fix-gpio-device-attribute-leak.patch
and it can be found in the queue-3.18 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <[email protected]> know about it.


>From 0915e6feb38de8d3601819992a5bd050201a56fa Mon Sep 17 00:00:00 2001
From: Johan Hovold <[email protected]>
Date: Tue, 13 Jan 2015 13:00:05 +0100
Subject: gpio: sysfs: fix gpio device-attribute leak

From: Johan Hovold <[email protected]>

commit 0915e6feb38de8d3601819992a5bd050201a56fa upstream.

The gpio device attributes were never destroyed when the gpio was
unexported (or on export failures).

Use device_create_with_groups() to create the default device attributes
of the gpio class device. Note that this also fixes the
attribute-creation race with userspace for these attributes.

Remove contingent attributes in export error path and on unexport.

Fixes: d8f388d8dc8d ("gpio: sysfs interface")
Signed-off-by: Johan Hovold <[email protected]>
Signed-off-by: Linus Walleij <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

---
 drivers/gpio/gpiolib-sysfs.c |   28 +++++++++++++---------------
 1 file changed, 13 insertions(+), 15 deletions(-)

--- a/drivers/gpio/gpiolib-sysfs.c
+++ b/drivers/gpio/gpiolib-sysfs.c
@@ -128,7 +128,7 @@ static ssize_t gpio_value_store(struct d
        return status;
 }
 
-static const DEVICE_ATTR(value, 0644,
+static DEVICE_ATTR(value, 0644,
                gpio_value_show, gpio_value_store);
 
 static irqreturn_t gpio_sysfs_irq(int irq, void *priv)
@@ -353,18 +353,15 @@ static ssize_t gpio_active_low_store(str
        return status ? : size;
 }
 
-static const DEVICE_ATTR(active_low, 0644,
+static DEVICE_ATTR(active_low, 0644,
                gpio_active_low_show, gpio_active_low_store);
 
-static const struct attribute *gpio_attrs[] = {
+static struct attribute *gpio_attrs[] = {
        &dev_attr_value.attr,
        &dev_attr_active_low.attr,
        NULL,
 };
-
-static const struct attribute_group gpio_attr_group = {
-       .attrs = (struct attribute **) gpio_attrs,
-};
+ATTRIBUTE_GROUPS(gpio);
 
 /*
  * /sys/class/gpio/gpiochipN/
@@ -561,18 +558,15 @@ int gpiod_export(struct gpio_desc *desc,
        if (desc->chip->names && desc->chip->names[offset])
                ioname = desc->chip->names[offset];
 
-       dev = device_create(&gpio_class, desc->chip->dev, MKDEV(0, 0),
-                           desc, ioname ? ioname : "gpio%u",
-                           desc_to_gpio(desc));
+       dev = device_create_with_groups(&gpio_class, desc->chip->dev,
+                                       MKDEV(0, 0), desc, gpio_groups,
+                                       ioname ? ioname : "gpio%u",
+                                       desc_to_gpio(desc));
        if (IS_ERR(dev)) {
                status = PTR_ERR(dev);
                goto fail_unlock;
        }
 
-       status = sysfs_create_group(&dev->kobj, &gpio_attr_group);
-       if (status)
-               goto fail_unregister_device;
-
        if (direction_may_change) {
                status = device_create_file(dev, &dev_attr_direction);
                if (status)
@@ -583,13 +577,15 @@ int gpiod_export(struct gpio_desc *desc,
                                       !test_bit(FLAG_IS_OUT, &desc->flags))) {
                status = device_create_file(dev, &dev_attr_edge);
                if (status)
-                       goto fail_unregister_device;
+                       goto fail_remove_attr_direction;
        }
 
        set_bit(FLAG_EXPORT, &desc->flags);
        mutex_unlock(&sysfs_lock);
        return 0;
 
+fail_remove_attr_direction:
+       device_remove_file(dev, &dev_attr_direction);
 fail_unregister_device:
        device_unregister(dev);
 fail_unlock:
@@ -723,6 +719,8 @@ void gpiod_unexport(struct gpio_desc *de
        mutex_unlock(&sysfs_lock);
 
        if (dev) {
+               device_remove_file(dev, &dev_attr_edge);
+               device_remove_file(dev, &dev_attr_direction);
                device_unregister(dev);
                put_device(dev);
        }


Patches currently in stable-queue which might be from [email protected] are

queue-3.18/gpio-fix-memory-and-reference-leaks-in-gpiochip_add-error-path.patch
queue-3.18/pinctrl-lantiq-remove-bogus-of_gpio_chip_add.patch
queue-3.18/gpio-sysfs-fix-gpio-device-attribute-leak.patch
queue-3.18/gpio-fix-memory-leak-and-sleep-while-atomic.patch
queue-3.18/gpio-sysfs-fix-gpio-chip-device-attribute-leak.patch
queue-3.18/gpio-fix-sleep-while-atomic-in-gpiochip_remove.patch
queue-3.18/leds-netxbig-fix-oops-at-probe-time.patch
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