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2015-03-26ALSA: control: Add sanity checks for user ctl id name stringTakashi Iwai
commit be3bb8236db2d0fcd705062ae2e2a9d75131222f upstream. There was no check about the id string of user control elements, so we accepted even a control element with an empty string, which is obviously bogus. This patch adds more sanity checks of id strings. Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-06-26ALSA: control: Make sure that id->index does not overflowLars-Peter Clausen
commit 883a1d49f0d77d30012f114b2e19fc141beb3e8e upstream. The ALSA control code expects that the range of assigned indices to a control is continuous and does not overflow. Currently there are no checks to enforce this. If a control with a overflowing index range is created that control becomes effectively inaccessible and unremovable since snd_ctl_find_id() will not be able to find it. This patch adds a check that makes sure that controls with a overflowing index range can not be created. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Acked-by: Jaroslav Kysela <perex@perex.cz> Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-06-26ALSA: control: Handle numid overflowLars-Peter Clausen
commit ac902c112d90a89e59916f751c2745f4dbdbb4bd upstream. Each control gets automatically assigned its numids when the control is created. The allocation is done by incrementing the numid by the amount of allocated numids per allocation. This means that excessive creation and destruction of controls (e.g. via SNDRV_CTL_IOCTL_ELEM_ADD/REMOVE) can cause the id to eventually overflow. Currently when this happens for the control that caused the overflow kctl->id.numid + kctl->count will also over flow causing it to be smaller than kctl->id.numid. Most of the code assumes that this is something that can not happen, so we need to make sure that it won't happen Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Acked-by: Jaroslav Kysela <perex@perex.cz> Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-06-26ALSA: control: Don't access controls outside of protected regionsLars-Peter Clausen
commit fd9f26e4eca5d08a27d12c0933fceef76ed9663d upstream. A control that is visible on the card->controls list can be freed at any time. This means we must not access any of its memory while not holding the controls_rw_lock. Otherwise we risk a use after free access. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Acked-by: Jaroslav Kysela <perex@perex.cz> Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-06-26ALSA: control: Fix replacing user controlsLars-Peter Clausen
commit 82262a46627bebb0febcc26664746c25cef08563 upstream. There are two issues with the current implementation for replacing user controls. The first is that the code does not check if the control is actually a user control and neither does it check if the control is owned by the process that tries to remove it. That allows userspace applications to remove arbitrary controls, which can cause a user after free if a for example a driver does not expect a control to be removed from under its feed. The second issue is that on one hand when a control is replaced the user_ctl_count limit is not checked and on the other hand the user_ctl_count is increased (even though the number of user controls does not change). This allows userspace, once the user_ctl_count limit as been reached, to repeatedly replace a control until user_ctl_count overflows. Once that happens new controls can be added effectively bypassing the user_ctl_count limit. Both issues can be fixed by instead of open-coding the removal of the control that is to be replaced to use snd_ctl_remove_user_ctl(). This function does proper permission checks as well as decrements user_ctl_count after the control has been removed. Note that by using snd_ctl_remove_user_ctl() the check which returns -EBUSY at beginning of the function if the control already exists is removed. This is not a problem though since the check is quite useless, because the lock that is protecting the control list is released between the check and before adding the new control to the list, which means that it is possible that a different control with the same settings is added to the list after the check. Luckily there is another check that is done while holding the lock in snd_ctl_add(), so we'll rely on that to make sure that the same control is not added twice. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Acked-by: Jaroslav Kysela <perex@perex.cz> Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-06-26ALSA: control: Protect user controls against concurrent accessLars-Peter Clausen
commit 07f4d9d74a04aa7c72c5dae0ef97565f28f17b92 upstream. The user-control put and get handlers as well as the tlv do not protect against concurrent access from multiple threads. Since the state of the control is not updated atomically it is possible that either two write operations or a write and a read operation race against each other. Both can lead to arbitrary memory disclosure. This patch introduces a new lock that protects user-controls from concurrent access. Since applications typically access controls sequentially than in parallel a single lock per card should be fine. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Acked-by: Jaroslav Kysela <perex@perex.cz> Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-03-12ALSA: add/change some comments describing function return valuesYacine Belkadi
script/kernel-doc reports the following type of warnings (when run in verbose mode): Warning(sound/core/init.c:152): No description found for return value of 'snd_card_create' To fix that: - add missing descriptions of function return values - use "Return:" sections to describe those return values Along the way: - complete some descriptions - fix some typos Signed-off-by: Yacine Belkadi <yacine.belkadi.1@gmail.com> Signed-off-by: Takashi Iwai <tiwai@suse.de>
2012-10-30ALSA: Avoid endless sleep after disconnectTakashi Iwai
When disconnect callback is called, each component should wake up sleepers and check card->shutdown flag for avoiding the endless sleep blocking the proper resource release. Cc: <stable@vger.kernel.org> Signed-off-by: Takashi Iwai <tiwai@suse.de>
2012-10-30ALSA: Add a reference counter to card instanceTakashi Iwai
For more strict protection for wild disconnections, a refcount is introduced to the card instance, and let it up/down when an object is referred via snd_lookup_*() in the open ops. The free-after-last-close check is also changed to check this refcount instead of the empty list, too. Reported-by: Matthieu CASTET <matthieu.castet@parrot.com> Cc: <stable@vger.kernel.org> Signed-off-by: Takashi Iwai <tiwai@suse.de>
2012-09-06ALSA: control: Fix missing VOLATILE flag at creating controlsTakashi Iwai
The SNDRV_CTL_ELEM_ACCESS_VOLATILE bit flag wasn't properly inherited at creating control elements via snd_ctl_new1(). Signed-off-by: Takashi Iwai <tiwai@suse.de>
2012-03-13ALSA: control - Fixe a trailing white space errorJeffrin Jose
Fixed a trailing white space error detected in sound/core/control.c by checkpatch.pl script. Signed-off-by: Jeffrin Jose <ahiliation@yahoo.co.in> Signed-off-by: Takashi Iwai <tiwai@suse.de>
2011-11-06Merge branch 'modsplit-Oct31_2011' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux * 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux: (230 commits) Revert "tracing: Include module.h in define_trace.h" irq: don't put module.h into irq.h for tracking irqgen modules. bluetooth: macroize two small inlines to avoid module.h ip_vs.h: fix implicit use of module_get/module_put from module.h nf_conntrack.h: fix up fallout from implicit moduleparam.h presence include: replace linux/module.h with "struct module" wherever possible include: convert various register fcns to macros to avoid include chaining crypto.h: remove unused crypto_tfm_alg_modname() inline uwb.h: fix implicit use of asm/page.h for PAGE_SIZE pm_runtime.h: explicitly requires notifier.h linux/dmaengine.h: fix implicit use of bitmap.h and asm/page.h miscdevice.h: fix up implicit use of lists and types stop_machine.h: fix implicit use of smp.h for smp_processor_id of: fix implicit use of errno.h in include/linux/of.h of_platform.h: delete needless include <linux/module.h> acpi: remove module.h include from platform/aclinux.h miscdevice.h: delete unnecessary inclusion of module.h device_cgroup.h: delete needless include <linux/module.h> net: sch_generic remove redundant use of <linux/module.h> net: inet_timewait_sock doesnt need <linux/module.h> ... Fix up trivial conflicts (other header files, and removal of the ab3550 mfd driver) in - drivers/media/dvb/frontends/dibx000_common.c - drivers/media/video/{mt9m111.c,ov6650.c} - drivers/mfd/ab3550-core.c - include/linux/dmaengine.h
2011-11-06ALSA: control: remove compilation warning on 32-bitOlof Johansson
This was introduced by 'ALSA: control: add support for ENUMERATED user space controls' which adds a u64 variable that gets cast to a pointer: sound/core/control.c: In function 'snd_ctl_elem_init_enum_names': sound/core/control.c:1089: warning: cast to pointer from integer of different size Cast to uintptr_t before casting to pointer to avoid the warning. Signed-off-by: Olof Johansson <olof@lixom.net> [cl: replace long with uintptr_t] Signed-off-by: Clemens Ladisch <clemens@ladisch.de> Signed-off-by: Takashi Iwai <tiwai@suse.de>
2011-10-31sound: Add module.h to the previously silent sound usersPaul Gortmaker
Lots of sound drivers were getting module.h via the implicit presence of it in <linux/device.h> but we are going to clean that up. So fix up those users now. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-10-09ALSA: control: add support for ENUMERATED user space controlsClemens Ladisch
Handling of user control elements was implemented for all types except ENUMERATED. This type will be needed for the device-specific mixers of upcoming FireWire drivers. Signed-off-by: Clemens Ladisch <clemens@ladisch.de> Signed-off-by: Takashi Iwai <tiwai@suse.de>
2011-08-24ALSA: core: release the constraint check for replace opsLu Guanqun
Suppose the ALSA card already has a number of MAX_USER_CONTROLS controls, and the user wants to replace one, it should not fail at this condition check. Signed-off-by: Lu Guanqun <guanqun.lu@intel.com> Signed-off-by: Takashi Iwai <tiwai@suse.de>
2011-08-24ALSA: core: trivial code style fixLu Guanqun
remove trailing tab on the line. Signed-off-by: Lu Guanqun <guanqun.lu@intel.com> Signed-off-by: Takashi Iwai <tiwai@suse.de>
2011-05-26ALSA: core: remove unused variables.Luca Tettamanti
Drop a few variables that are never read. Signed-off-by: Luca Tettamanti <kronos.it@gmail.com> Signed-off-by: Takashi Iwai <tiwai@suse.de>
2011-03-22ALSA: Add snd_ctl_replace() to dynamically replace a controlDimitris Papastamos
Add a function to dynamically replace a given control. If the control does not already exist, a third parameter is used to determine whether to actually add that control. This is useful in cases where downloadable firmware at runtime can add or replace existing controls. A separate patch needs to be made to allow ALSA Mixer to render the replaced controls on the fly. Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Signed-off-by: Takashi Iwai <tiwai@suse.de>
2011-03-18Merge branch 'topic/misc' into for-linusTakashi Iwai
2011-03-11ALSA: Add snd_ctl_activate_id()Takashi Iwai
Added a new API function snd_ctl_activate_id() for activate / inactivate the control element dynamically. Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-03-08ALSA: control: clean up snd_ctl_hole_check()Clemens Ladisch
The return value of snd_ctl_hole_check() is used only to detect whether to continue the loop in snd_ctl_find_hole() or not, so we can simplify the code by changing this return type to a boolean. Also rename this function to better show what it actually does. Signed-off-by: Clemens Ladisch <clemens@ladisch.de> Signed-off-by: Takashi Iwai <tiwai@suse.de>
2011-03-08ALSA: control: fix numid conflict check for new controlsClemens Ladisch
The purpose of the snd_ctl_hole_check() function is to find conflicts between the numerical IDs of the new control and those of any existing controls. However, it would fail to detect an existing control whose count is smaller than the new control's count and whose interval of IDs is entirely contained in the interval of the new control's IDs. To fix this, use the correct formula to detect overlapping intervals, which happens to simplify the condition. This problem was not encountered so far because ALSA does not yet allow drivers to allocate specific control IDs. Signed-off-by: Clemens Ladisch <clemens@ladisch.de> Signed-off-by: Takashi Iwai <tiwai@suse.de>
2011-01-10ALSA: core, oxygen, virtuoso: add an enum control info helperClemens Ladisch
Introduce the helper function snd_ctl_enum_info() to fill out the elem_info fields for an enumerated control. Signed-off-by: Clemens Ladisch <clemens@ladisch.de> Signed-off-by: Takashi Iwai <tiwai@suse.de>
2010-09-28ALSA: prevent heap corruption in snd_ctl_new()Dan Rosenberg
The snd_ctl_new() function in sound/core/control.c allocates space for a snd_kcontrol struct by performing arithmetic operations on a user-provided size without checking for integer overflow. If a user provides a large enough size, an overflow will occur, the allocated chunk will be too small, and a second user-influenced value will be written repeatedly past the bounds of this chunk. This code is reachable by unprivileged users who have permission to open a /dev/snd/controlC* device (on many distros, this is group "audio") via the SNDRV_CTL_IOCTL_ELEM_ADD and SNDRV_CTL_IOCTL_ELEM_REPLACE ioctls. Signed-off-by: Dan Rosenberg <drosenberg@vsecurity.com> Cc: <stable@kernel.org> Signed-off-by: Takashi Iwai <tiwai@suse.de>
2010-04-13ALSA: core - Define llseek fopsTakashi Iwai
Set no_llseek to llseek file ops of each sound component (but for hwdep). This avoids the implicit BKL invocation via generic_file_llseek() used as default when fops.llseek is NULL. Also call nonseekable_open() at each open ops to ensure the file flags have no seek bit. Signed-off-by: Takashi Iwai <tiwai@suse.de>
2010-02-01sound: control: fix minimum TLV lengthClemens Ladisch
Allow TLV blocks that do not have any values; the smallest possible TLV is an empty container or one where the information is only in the tag. Signed-off-by: Clemens Ladisch <clemens@ladisch.de> Signed-off-by: Jaroslav Kysela <perex@perex.cz>
2010-02-01sound: control: actually allow TLV command accessClemens Ladisch
Creating a control with TLV_COMMAND access was not possible because snd_ctl_new1() forgot to include it in the mask of allowable access bits. Signed-off-by: Clemens Ladisch <clemens@ladisch.de> Signed-off-by: Jaroslav Kysela <perex@perex.cz>
2009-12-04Merge branch 'topic/misc' into for-linusTakashi Iwai
2009-11-18ALSA: remove unnecessary null checkDan Carpenter
This function is only called from snd_ctl_ioctl() and the file parameter can never be null so there is no need to check it here. We dereference file at the start of the function: struct snd_card *card = file->card; and it confuses static checkers to dereference a pointer before checking it. Signed-off-by: Dan Carpenter <error27@gmail.com> Signed-off-by: Takashi Iwai <tiwai@suse.de>
2009-11-06control: use reference-counted pidClemens Ladisch
Instead of storing the PID number, take a reference to the task's pid structure. This protects against duplicates due to PID overflows, and using pid_vnr() ensures that the PID returned by snd_ctl_elem_info() is correct as seen from the current namespace. Signed-off-by: Clemens Ladisch <clemens@ladisch.de> Signed-off-by: Takashi Iwai <tiwai@suse.de>
2009-11-06control: remove snd_konctrol_volatile::owner_pid fieldClemens Ladisch
We do not need to save the ID of the process that locked a control because that information is already available in the owner's file data. Signed-off-by: Clemens Ladisch <clemens@ladisch.de> Signed-off-by: Takashi Iwai <tiwai@suse.de>
2009-08-17sound: snd_ctl_remove_user_ctl: prevent removal of kernel controlsClemens Ladisch
Ensure that userspace can remove only user controls. Controls created by kernel drivers must not be removed because they might be referenced in calls to snd_ctl_notify(). Signed-off-by: Clemens Ladisch <clemens@ladisch.de> Signed-off-by: Takashi Iwai <tiwai@suse.de>
2009-08-17sound: snd_ctl_remove_unlocked_id: simplify user control countingClemens Ladisch
Move the decrementing of the user controls counter from snd_ctl_elem_remove to snd_ctl_remove_unlocked_id; this saves the separate locking of the controls semaphore, and therefore removes a harmless race. Since the purpose of the function is to operate on user controls (the control being unlocked is just a prerequisite), rename it to snd_ctl_remove_user_ctl. Signed-off-by: Clemens Ladisch <clemens@ladisch.de> Signed-off-by: Takashi Iwai <tiwai@suse.de>
2009-08-17sound: snd_ctl_remove_unlocked_id: simplify error pathsClemens Ladisch
Use a common exit path to release the mutex and to return a possible error. Signed-off-by: Clemens Ladisch <clemens@ladisch.de> Signed-off-by: Takashi Iwai <tiwai@suse.de>
2009-08-17sound: snd_ctl_elem_add: fix value count checkClemens Ladisch
Make sure that no user element that has no values can be added. The check for count>1024 is not needed because the count is checked later for the individual control types. Signed-off-by: Clemens Ladisch <clemens@ladisch.de> Signed-off-by: Takashi Iwai <tiwai@suse.de>
2009-04-14ALSA: sound/core: use memdup_user()Li Zefan
Remove open-coded memdup_user(). Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Signed-off-by: Takashi Iwai <tiwai@suse.de>
2009-03-16Rationalize fasync return valuesJonathan Corbet
Most fasync implementations do something like: return fasync_helper(...); But fasync_helper() will return a positive value at times - a feature used in at least one place. Thus, a number of other drivers do: err = fasync_helper(...); if (err < 0) return err; return 0; In the interests of consistency and more concise code, it makes sense to map positive return values onto zero where ->fasync() is called. Cc: Al Viro <viro@ZenIV.linux.org.uk> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2008-11-01saner FASYNC handling on file closeAl Viro
As it is, all instances of ->release() for files that have ->fasync() need to remember to evict file from fasync lists; forgetting that creates a hole and we actually have a bunch that *does* forget. So let's keep our lives simple - let __fput() check FASYNC in file->f_flags and call ->fasync() there if it's been set. And lose that crap in ->release() instances - leaving it there is still valid, but we don't have to bother anymore. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-29ALSA: Warn when control names are truncatedMark Brown
This is likely to confuse user interfaces since the end of the control name is interpreted (eg, "Volume", "Switch"). Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Takashi Iwai <tiwai@suse.de>
2008-09-09ALSA: use correct lock in snd_ctl_dev_disconnect()Takashi Iwai
The lock used in snd_ctl_dev_disconnect() should be card->ctl_files_rwlock for protection of card->ctl_files entries, instead of card->controls_rwsem. Reported-by: Vegard Nossum <vegard.nossum@gmail.com> Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Jaroslav Kysela <perex@perex.cz>
2008-08-13ALSA: Kill snd_assert() in sound/core/*Takashi Iwai
Kill snd_assert() in sound/core/*, either removed or replaced with if () with snd_BUG_ON(). Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Jaroslav Kysela <perex@perex.cz>
2008-06-13ALSA: make snd_ctl_elem_read() and snd_ctl_elem_write() staticTakashi Iwai
snd_ctl_elem_read() and snd_ctl_elem_write() are no longer used by any other drivers. Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Jaroslav Kysela <perex@perex.cz>
2008-01-31[ALSA] Remove sound/driver.hTakashi Iwai
This header file exists only for some hacks to adapt alsa-driver tree. It's useless for building in the kernel. Let's move a few lines in it to sound/core.h and remove it. With this patch, sound/driver.h isn't removed but has just a single compile warning to include it. This should be really killed in future. Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Jaroslav Kysela <perex@perex.cz>
2008-01-31[ALSA] Remove indirect control accessTakashi Iwai
This patch removes the indirect control access to the control elements. The indirect access has never been used and is even broken on 32bit ioctl wrapper. Let's clean it up. The pointers still remain in snd_ctl_elem_* structs just to make sure that the struct size won't change. Once after checking the size consistency, we can get rid of them, too. Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Jaroslav Kysela <perex@perex.cz>
2007-10-23[ALSA] sound/core/control.c: hard-irq-safe -> hard-irq-unsafe lock warningBorislav Petkov
The lock grabbed in snd_ctl_empty_read_queue() is hardirq-unsafe but we hold an hardirq-safe one already, so make the &ctl->read_lock also hard-irq-safe. Signed-off-by: Borislav Petkov <bbpetkov@yahoo.de> Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Jaroslav Kysela <perex@perex.cz>
2007-10-16[ALSA] Changed Jaroslav Kysela's e-mail from perex@suse.cz to perex@perex.czJaroslav Kysela
Signed-off-by: Jaroslav Kysela <perex@perex.cz>
2007-10-16[ALSA] unexport snd_ctl_elem_{read,write}Adrian Bunk
snd_ctl_elem_{read,write} no longer have any modular users Signed-off-by: Adrian Bunk <bunk@kernel.org> Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Jaroslav Kysela <perex@suse.cz>
2007-10-16[ALSA] Add helper functions for frequently used callbacksTakashi Iwai
Added helper functions for frequenty used callbacks: snd_ctl_boolean_mono_info() and snd_ctl_boolean_stereo_info() Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Jaroslav Kysela <perex@suse.cz>
2007-05-08header cleaning: don't include smp_lock.h when not usedRandy Dunlap
Remove includes of <linux/smp_lock.h> where it is not used/needed. Suggested by Al Viro. Builds cleanly on x86_64, i386, alpha, ia64, powerpc, sparc, sparc64, and arm (all 59 defconfigs). Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>