From mboxrd@z Thu Jan 1 00:00:00 1970 From: Johan Hovold Subject: [PATCH 2/2] gpio: sysfs: fix gpio device-attribute leak Date: Mon, 26 Jan 2015 19:04:56 +0100 Message-ID: <1422295496-6194-3-git-send-email-johan@kernel.org> References: <1422295496-6194-1-git-send-email-johan@kernel.org> Return-path: Received: from mail-lb0-f180.google.com ([209.85.217.180]:44314 "EHLO mail-lb0-f180.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755636AbbAZSF1 (ORCPT ); Mon, 26 Jan 2015 13:05:27 -0500 In-Reply-To: <1422295496-6194-1-git-send-email-johan@kernel.org> Sender: linux-gpio-owner@vger.kernel.org List-Id: linux-gpio@vger.kernel.org To: Greg Kroah-Hartman Cc: Linus Walleij , linux-gpio@vger.kernel.org, linux-kernel@vger.kernel.org, Johan Hovold , stable 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") Cc: stable # v2.6.27+ Signed-off-by: Johan Hovold Signed-off-by: Linus Walleij Signed-off-by: Johan Hovold --- drivers/gpio/gpiolib.c | 27 +++++++++++++-------------- 1 file changed, 13 insertions(+), 14 deletions(-) diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c index dd4d6ffacc30..8380709b66d2 100644 --- a/drivers/gpio/gpiolib.c +++ b/drivers/gpio/gpiolib.c @@ -362,7 +362,7 @@ static ssize_t gpio_value_store(struct device *dev, 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) @@ -580,18 +580,16 @@ static ssize_t gpio_active_low_store(struct device *dev, 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/ @@ -788,18 +786,15 @@ static int gpiod_export(struct gpio_desc *desc, bool direction_may_change) 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) @@ -810,13 +805,15 @@ static int gpiod_export(struct gpio_desc *desc, bool direction_may_change) !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: @@ -959,6 +956,8 @@ static void gpiod_unexport(struct gpio_desc *desc) dev = class_find_device(&gpio_class, NULL, desc, match_export); if (dev) { + device_remove_file(dev, &dev_attr_edge); + device_remove_file(dev, &dev_attr_direction); gpio_setup_irq(desc, dev, 0); clear_bit(FLAG_EXPORT, &desc->flags); } else -- 2.0.5