linux-toradex.git/drivers/gpio/gpiolib.c, branch v3.10.80 Linux kernel for Apalis and Colibri modules gpio: sysfs: fix memory leaks and device hotplug 2015-05-17T16:51:32+00:00 Johan Hovold johan@kernel.org 2015-04-21T15:42:09+00:00 a1f3ecb1f721e5d393f28898350fe3c75fde4c93 commit 483d821108791092798f5d230686868112927044 upstream. Unregister GPIOs requested through sysfs at chip remove to avoid leaking the associated memory and sysfs entries. The stale sysfs entries prevented the gpio numbers from being exported when the gpio range was later reused (e.g. at device reconnect). This also fixes the related module-reference leak. Note that kernfs makes sure that any on-going sysfs operations finish before the class devices are unregistered and that further accesses fail. The chip exported flag is used to prevent gpiod exports during removal. This also makes it harder to trigger, but does not fix, the related race between gpiochip_remove and export_store, which is really a race with gpiod_request that needs to be addressed separately. Also note that this would prevent the crashes (e.g. NULL-dereferences) at reconnect that affects pre-3.18 kernels, as well as use-after-free on operations on open attribute files on pre-3.14 kernels (prior to kernfs). Fixes: d8f388d8dc8d ("gpio: sysfs interface") Signed-off-by: Johan Hovold <johan@kernel.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 483d821108791092798f5d230686868112927044 upstream.

Unregister GPIOs requested through sysfs at chip remove to avoid leaking
the associated memory and sysfs entries.

The stale sysfs entries prevented the gpio numbers from being exported
when the gpio range was later reused (e.g. at device reconnect).

This also fixes the related module-reference leak.

Note that kernfs makes sure that any on-going sysfs operations finish
before the class devices are unregistered and that further accesses
fail.

The chip exported flag is used to prevent gpiod exports during removal.
This also makes it harder to trigger, but does not fix, the related race
between gpiochip_remove and export_store, which is really a race with
gpiod_request that needs to be addressed separately.

Also note that this would prevent the crashes (e.g. NULL-dereferences)
at reconnect that affects pre-3.18 kernels, as well as use-after-free on
operations on open attribute files on pre-3.14 kernels (prior to
kernfs).

Fixes: d8f388d8dc8d ("gpio: sysfs interface")
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
gpio: unregister gpiochip device before removing it 2015-05-17T16:51:32+00:00 Johan Hovold johan@kernel.org 2015-01-12T16:12:29+00:00 864c329b21a1914105a9e591b49def3f30184b65 commit 01cca93a9491ed95992523ff7e79dd9bfcdea8e0 upstream. Unregister gpiochip device (used to export information through sysfs) before removing it internally. This way removal will reverse addition. Signed-off-by: Johan Hovold <johan@kernel.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 01cca93a9491ed95992523ff7e79dd9bfcdea8e0 upstream.

Unregister gpiochip device (used to export information through sysfs)
before removing it internally. This way removal will reverse addition.

Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
gpio: sysfs: fix memory leak in gpiod_sysfs_set_active_low 2015-02-11T06:48:16+00:00 Johan Hovold johan@kernel.org 2015-01-26T11:02:46+00:00 4cd925d7c1d5d777f2f09db4aee4675d0978a95b commit 49d2ca84e433dab854c7a866bc6add09cfab682d upstream. Fix memory leak in the gpio sysfs interface due to failure to drop reference to device returned by class_find_device when setting the gpio-line polarity. Fixes: 0769746183ca ("gpiolib: add support for changing value polarity in sysfs") Signed-off-by: Johan Hovold <johan@kernel.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 49d2ca84e433dab854c7a866bc6add09cfab682d upstream.

Fix memory leak in the gpio sysfs interface due to failure to drop
reference to device returned by class_find_device when setting the
gpio-line polarity.

Fixes: 0769746183ca ("gpiolib: add support for changing value polarity in sysfs")
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
gpio: sysfs: fix memory leak in gpiod_export_link 2015-02-11T06:48:16+00:00 Johan Hovold johan@kernel.org 2015-01-26T11:02:45+00:00 d0d1f54d367f959bc7484422fb51f61c00977a64 commit 0f303db08df0df9bd0966443ad6001e63960af16 upstream. Fix memory leak in the gpio sysfs interface due to failure to drop reference to device returned by class_find_device when creating a link. Fixes: a4177ee7f1a8 ("gpiolib: allow exported GPIO nodes to be named using sysfs links") Signed-off-by: Johan Hovold <johan@kernel.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 0f303db08df0df9bd0966443ad6001e63960af16 upstream.

Fix memory leak in the gpio sysfs interface due to failure to drop
reference to device returned by class_find_device when creating a link.

Fixes: a4177ee7f1a8 ("gpiolib: allow exported GPIO nodes to be named using sysfs links")
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
gpio: sysfs: fix gpio device-attribute leak 2015-01-30T01:40:55+00:00 Johan Hovold johan@kernel.org 2015-01-13T12:00:05+00:00 a9808403cc6086147f99e3d6f27961fa108f4fe3 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 <stable@vger.kernel.org> # v2.6.27+ Signed-off-by: Johan Hovold <johan@kernel.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
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 <stable@vger.kernel.org>	# v2.6.27+
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
gpio: sysfs: fix gpio-chip device-attribute leak 2015-01-30T01:40:55+00:00 Johan Hovold johan@kernel.org 2015-01-13T12:00:04+00:00 aa35a487040862e568968dbcf34aad0827eba588 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> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
gpiolib: move comment to right function 2013-03-02T13:20:20+00:00 Alexandre Courbot acourbot@nvidia.com 2013-02-15T05:46:16+00:00 24d7628fe8b10bb3770a11ddf71719613832a298 This comment applies to gpio_to_chip(), not gpiod_to_chip(). Signed-off-by: Alexandre Courbot <acourbot@nvidia.com> Signed-off-by: Grant Likely <grant.likely@secretlab.ca> 
This comment applies to gpio_to_chip(), not gpiod_to_chip().

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
gpiolib: use const parameters when possible 2013-03-02T13:20:19+00:00 Alexandre Courbot acourbot@nvidia.com 2013-02-15T05:46:15+00:00 def634338d3ffb32fbe9b0a2d70cc24ef909cd4f Constify descriptor parameter of gpiod_* functions for those that should obviously not modify it. This includes value or direction get, cansleep, and IRQ number query. Signed-off-by: Alexandre Courbot <acourbot@nvidia.com> Signed-off-by: Grant Likely <grant.likely@secretlab.ca> 
Constify descriptor parameter of gpiod_* functions for those that
should obviously not modify it. This includes value or direction get,
cansleep, and IRQ number query.

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
gpiolib: check descriptors validity before use 2013-03-02T13:20:19+00:00 Alexandre Courbot acourbot@nvidia.com 2013-02-15T05:46:14+00:00 bcabdef12da49878789464ad7239e97d83ea5ef5 Some functions dereferenced their GPIO descriptor argument without checking its validity first, potentially leading to an oops when given an invalid argument. This patch also makes gpio_get_value() more resilient when given an invalid GPIO, returning 0 instead of silently crashing. Signed-off-by: Alexandre Courbot <acourbot@nvidia.com> Cc: Ryan Mallon <rmallon@gmail.com> Signed-off-by: Grant Likely <grant.likely@secretlab.ca> 
Some functions dereferenced their GPIO descriptor argument without
checking its validity first, potentially leading to an oops when given
an invalid argument.

This patch also makes gpio_get_value() more resilient when given an
invalid GPIO, returning 0 instead of silently crashing.

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Cc: Ryan Mallon <rmallon@gmail.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
gpio: convert to idr_alloc() 2013-02-28T03:10:15+00:00 Tejun Heo tj@kernel.org 2013-02-28T01:04:06+00:00 62f516b8d6b0610c257b4f92264e00a8dee77a0b Convert to the much saner new idr interface. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Linus Walleij <linus.walleij@linaro.org> Cc: Grant Likely <grant.likely@secretlab.ca> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> 
Convert to the much saner new idr interface.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Cc: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>