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 19:06:00 +0100 Message-ID: <1422295560-6284-3-git-send-email-johan@kernel.org> References: <1422295496-6194-1-git-send-email-johan@kernel.org> <1422295560-6284-1-git-send-email-johan@kernel.org> Return-path: Received: from mail-lb0-f178.google.com ([209.85.217.178]:33419 "EHLO mail-lb0-f178.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757125AbbAZSGQ (ORCPT ); Mon, 26 Jan 2015 13:06:16 -0500 In-Reply-To: <1422295560-6284-1-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 [johan: fix leaks without device_create_with_groups, which wasn't introduced until 3.11 ] Signed-off-by: Johan Hovold --- drivers/gpio/gpiolib.c | 19 +++++++++++++------ 1 file changed, 13 insertions(+), 6 deletions(-) diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c index bc3d59efe80b..4b2a26b62025 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) @@ -580,17 +580,17 @@ 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, + .attrs = gpio_attrs, }; /* @@ -806,20 +806,24 @@ static int gpiod_export(struct gpio_desc *desc, bool direction_may_change) if (direction_may_change) { status = device_create_file(dev, &dev_attr_direction); if (status) - goto fail_unregister_device; + goto fail_remove_attr_group; } if (gpiod_to_irq(desc) >= 0 && (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_remove_attr_group: + sysfs_remove_group(&dev->kobj, &gpio_attr_group); fail_unregister_device: device_unregister(dev); fail_unlock: @@ -962,6 +966,9 @@ 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); + sysfs_remove_group(&dev->kobj, &gpio_attr_group); gpio_setup_irq(desc, dev, 0); clear_bit(FLAG_EXPORT, &desc->flags); } else -- 2.0.5