From: Johan Hovold <johan@kernel.org>
Date: Tue, 13 Jan 2015 12:00:04 +0000 (+0100)
Subject: gpio: sysfs: fix gpio-chip device-attribute leak
X-Git-Tag: v3.2.67~41
X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=6f7c3121580136cfcdfb07cf9d3f6f81d78d39dc;p=pandora-kernel.git

gpio: sysfs: fix gpio-chip device-attribute leak

commit 121b6a79955a3a3fd7bbb9b8cb88d5b9dad6283d upstream.

The gpio-chip device attributes were never destroyed when the device was
removed.

Fix by using device_create_with_groups() to create the device attributes
of the chip class device.

Note that this also fixes the attribute-creation race with userspace.

Fixes: d8f388d8dc8d ("gpio: sysfs interface")
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
[bwh: Backported to 3.2: adjust filename]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---

diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index 503104af0ed2..f4e4363ea0fc 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -587,16 +587,13 @@ static ssize_t chip_ngpio_show(struct device *dev,
 }
 static DEVICE_ATTR(ngpio, 0444, chip_ngpio_show, NULL);
 
-static const struct attribute *gpiochip_attrs[] = {
+static struct attribute *gpiochip_attrs[] = {
 	&dev_attr_base.attr,
 	&dev_attr_label.attr,
 	&dev_attr_ngpio.attr,
 	NULL,
 };
-
-static const struct attribute_group gpiochip_attr_group = {
-	.attrs = (struct attribute **) gpiochip_attrs,
-};
+ATTRIBUTE_GROUPS(gpiochip);
 
 /*
  * /sys/class/gpio/export ... write-only
@@ -918,13 +915,13 @@ static int gpiochip_export(struct gpio_chip *chip)
 
 	/* use chip->base for the ID; it's already known to be unique */
 	mutex_lock(&sysfs_lock);
-	dev = device_create(&gpio_class, chip->dev, MKDEV(0, 0), chip,
-				"gpiochip%d", chip->base);
-	if (!IS_ERR(dev)) {
-		status = sysfs_create_group(&dev->kobj,
-				&gpiochip_attr_group);
-	} else
+	dev = device_create_with_groups(&gpio_class, chip->dev, MKDEV(0, 0),
+					chip, gpiochip_groups,
+					"gpiochip%d", chip->base);
+	if (IS_ERR(dev))
 		status = PTR_ERR(dev);
+	else
+		status = 0;
 	chip->exported = (status == 0);
 	mutex_unlock(&sysfs_lock);