Commit Graph

189 Commits

Author SHA1 Message Date
Takashi Iwai
0c436dfe5c ASoC: Fixes for v6.12
A bunch of fixes here that came in during the merge window and the first
 week of release, plus some new quirks and device IDs.  There's nothing
 major here, it's a bit bigger than it might've been due to there being
 no fixes sent during the merge window due to your vacation.
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Merge tag 'asoc-fix-v6.12-rc1' of https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into for-linus

ASoC: Fixes for v6.12

A bunch of fixes here that came in during the merge window and the first
week of release, plus some new quirks and device IDs.  There's nothing
major here, it's a bit bigger than it might've been due to there being
no fixes sent during the merge window due to your vacation.
2024-10-02 21:29:16 +02:00
Dan Carpenter
a04dae6fa4 ALSA: silence integer wrapping warning
This patch doesn't change runtime at all, it's just for kernel hardening.

The "count" here comes from the user and on 32bit systems, it leads to
integer wrapping when we pass it to compute_user_elem_size():

	alloc_size = compute_user_elem_size(private_size, count);

However, the integer over is harmless because later "count" is checked
when we pass it to snd_ctl_new():

	err = snd_ctl_new(&kctl, count, access, file);

These days as part of kernel hardening we're trying to avoid integer
overflows when they affect size_t type.  So to avoid the integer overflow
copy the check from snd_ctl_new() and do it at the start of the
snd_ctl_elem_add() function as well.

Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Reviewed-by: Jaroslav Kysela <perex@perex.cz>
Link: https://patch.msgid.link/5457e8c1-01ff-4dd9-b49c-15b817f65ee7@stanley.mountain
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2024-10-01 14:56:40 +02:00
Al Viro
cb787f4ac0 [tree-wide] finally take no_llseek out
no_llseek had been defined to NULL two years ago, in commit 868941b144
("fs: remove no_llseek")

To quote that commit,

  At -rc1 we'll need do a mechanical removal of no_llseek -

  git grep -l -w no_llseek | grep -v porting.rst | while read i; do
	sed -i '/\<no_llseek\>/d' $i
  done

  would do it.

Unfortunately, that hadn't been done.  Linus, could you do that now, so
that we could finally put that thing to rest? All instances are of the
form
	.llseek = no_llseek,
so it's obviously safe.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2024-09-27 08:18:43 -07:00
Takashi Iwai
40a024b81d ALSA: core: Drop superfluous no_free_ptr() for memdup_user() errors
We used to wrap with no_free_ptr() for the return value from
memdup_user() with errors where the auto cleanup is applied.  This was
a workaround because the initial implementation of kfree auto-cleanup
checked only NULL pointers.

Since recently, though, the kfree auto-cleanup checks with
IS_ERR_OR_NULL() (by the commit cd7eb8f83f ("mm/slab: make
__free(kfree) accept error pointers")), hence those workarounds became
superfluous.  Let's drop them now.

Link: https://patch.msgid.link/20240902075246.3743-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2024-09-02 10:21:41 +02:00
Takashi Iwai
4004f3029e Merge branch 'topic/control-lookup-rwlock' into for-next
Pull control lookup optimization changes.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2024-08-09 14:25:24 +02:00
Takashi Iwai
38ea4c3dc3 ALSA: control: Optimize locking for look-up
For a fast look-up of a control element via either numid or name
matching (enabled via CONFIG_SND_CTL_FAST_LOOKUP), a locking isn't
needed at all thanks to Xarray.  OTOH, the locking is still needed for
a slow linked-list traversal, and that's rather a rare case.

In this patch, we reduce the use of locking at snd_ctl_find_*() API
functions, and switch from controls_rwsem to controls_rwlock for
avoiding unnecessary lock inversions.  This also resulted in a nice
cleanup, as *_unlocked() version of snd_ctl_find_*() APIs can be
dropped.

snd_ctl_find_id_mixer_unlocked() is still left just as an alias of
snd_ctl_find_id_mixer(), since soc-card.c has a wrapper and there are
several users.  Once after converting there, we can remove it later.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Link: https://patch.msgid.link/20240809104234.8488-3-tiwai@suse.de
2024-08-09 14:24:55 +02:00
Takashi Iwai
f428cc9eac ALSA: control: Rename ctl_files_rwlock to controls_rwlock
We'll re-use the existing rwlock for the protection of control list
lookup, too, and now rename it to a more generic name.

This is a preliminary change, only the rename of the struct field
here, no functional changes.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Link: https://patch.msgid.link/20240809104234.8488-2-tiwai@suse.de
2024-08-09 14:24:55 +02:00
Takashi Iwai
fef1ac950c ALSA: control: Fix leftover snd_power_unref()
One snd_power_unref() was forgotten and left at __snd_ctl_elem_info()
in the previous change for reorganizing the locking order.

Fixes: fcc62b1910 ("ALSA: control: Take power_ref lock primarily")
Link: https://github.com/thesofproject/linux/pull/5127
Link: https://patch.msgid.link/20240801064203.30284-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2024-08-01 08:42:42 +02:00
Takashi Iwai
fcc62b1910 ALSA: control: Take power_ref lock primarily
The code path for kcontrol accesses have often nested locks of both
card's controls_rwsem and power_ref, and applies in that order.
However, what could take much longer is the latter, power_ref; it
waits for the power state of the device, and it pretty much depends on
the user's action.

This patch swaps the locking order of those locks to a more natural
way, namely, power_ref -> controls_rwsem, in order to shorten the time
of possible nested locks.  For consistency, power_ref is taken always
in the top-level caller side (that is, *_user() functions and the
ioctl handler itself).

Link: https://patch.msgid.link/20240729160659.4516-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2024-07-30 07:46:00 +02:00
Takashi Iwai
4e9652003b ALSA: control: Annotate snd_kcontrol with __counted_by()
struct snd_kcontrol contains a flex array of snd_kcontrol_volatile
objects at its end, and the array size is stored in count field.
This can be annotated gracefully with __counted_by() for catching
possible array overflows.

One additional change is the order of the count field initialization;
The assignment of the count field is moved before assignment of vd[]
elements for avoiding false-positive warnings from compilers.

Link: https://patch.msgid.link/20240726152840.8629-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2024-07-30 07:45:37 +02:00
Takashi Iwai
e946455ce1 ALSA: control: Allow NULL passed to snd_ctl_remove()
There are lots of code checking NULL for kcontrol passed to
snd_ctl_remove() in the caller side.  Let's make snd_ctl_remove()
accepting the NULL kcontrol instead a la free(), so that we can clean
up the caller side.

Link: https://lore.kernel.org/20240617100529.6667-2-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2024-06-18 12:51:35 +02:00
Takashi Iwai
50ed081284 ALSA: control: Apply sanity check of input values for user elements
Although we have already a mechanism for sanity checks of input values
for control writes, it's not applied unless the kconfig
CONFIG_SND_CTL_INPUT_VALIDATION is set due to the performance reason.
Nevertheless, it still makes sense to apply the same check for user
elements despite of its cost, as that's the only way to filter out the
invalid values; the user controls are handled solely in ALSA core
code, and there is no corresponding driver, after all.

This patch adds the same input value validation for user control
elements at its put callback.  The kselftest will be happier with this
change, as the incorrect values will be bailed out now with errors.

For other normal controls, the check is applied still only when
CONFIG_SND_CTL_INPUT_VALIDATION is set.

Reported-by: Paul Menzel <pmenzel@molgen.mpg.de>
Closes: https://lore.kernel.org/r/1d44be36-9bb9-4d82-8953-5ae2a4f09405@molgen.mpg.de
Reviewed-by: Jaroslav Kysela <perex@perex.cz>
Reviewed-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Link: https://lore.kernel.org/20240616073454.16512-4-tiwai@suse.de
2024-06-18 12:00:18 +02:00
Takashi Iwai
14d811467f ALSA: control: Fix unannotated kfree() cleanup
The recent conversion to the automatic kfree() forgot to mark a
variable with __free(kfree), leading to memory leaks.  Fix it.

Fixes: 1052d98822 ("ALSA: control: Use automatic cleanup of kfree()")
Reported-by: Mirsad Todorovac <mirsad.todorovac@alu.unizg.hr>
Closes: https://lore.kernel.org/r/c1e2ef3c-164f-4840-9b1c-f7ca07ca422a@alu.unizg.hr
Message-ID: <20240320062722.31325-1-tiwai@suse.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2024-03-20 07:30:48 +01:00
Takashi Iwai
471be437be ALSA: control: Use guard() for locking
We can simplify the code gracefully with new guard() macro and co for
automatic cleanup of locks.

The lops calls under multiple rwsems are factored out as a simple
macro, so that it can be called easily from snd_ctl_dev_register()
and snd_ctl_dev_disconnect().

There are a few remaining explicit rwsem and spinlock calls, and those
are the places where the lock downgrade happens or where the temporary
unlock/relocking happens -- which guard() doens't cover well yet.

Only the code refactoring, and no functional changes.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Link: https://lore.kernel.org/r/20240227085306.9764-9-tiwai@suse.de
2024-02-28 15:01:21 +01:00
Takashi Iwai
1052d98822 ALSA: control: Use automatic cleanup of kfree()
There are common patterns where a temporary buffer is allocated and
freed at the exit, and those can be simplified with the recent cleanup
mechanism via __free(kfree).

A caveat is that some allocations are memdup_user() and they return an
error pointer instead of NULL.  Those need special cares and the value
has to be cleared with no_free_ptr() at the allocation error path.

Other than that, the conversions are straightforward.

No functional changes, only code refactoring.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Link: https://lore.kernel.org/r/20240222111509.28390-3-tiwai@suse.de
2024-02-23 10:57:30 +01:00
Takashi Iwai
6a66b01de4 ALSA: control: Don't embed ctl_dev
Embedding the ctl_dev in the snd_card object may result in UAF when
the delayed kobj release is used; at the delayed kobj release, it
still accesses the struct device itself while the card memory (that
embeds the struct device) may be already gone.

As a workaround, detach the struct device from the card object by
allocating via the new snd_device_alloc() helper.  The rest are just
replacing ctl_dev access to the pointer.

This is based on the fix Curtis posted initially.  In this patch, the
changes are split and use the new helper function instead.

Link: https://lore.kernel.org/r/20230801171928.1460120-1-cujomalainey@chromium.org
Reviewed-by: Jaroslav Kysela <perex@perex.cz>
Signed-off-by: Curtis Malainey <cujomalainey@chromium.org>
Tested-by: Curtis Malainey <cujomalainey@chromium.org>
Link: https://lore.kernel.org/r/20230816160252.23396-3-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2023-08-17 09:23:30 +02:00
Takashi Iwai
9c2cc5652e ALSA: control: Take lock in snd_ctl_find_id() and snd_ctl_find_numid()
Now all needed callers have been replaced with *_locked() versions,
let's turn on the locking in snd_ctl_find_id() and
snd_ctl_find_numid().

This patch also adds the lockdep assertions for debugging, too.

Link: https://lore.kernel.org/r/20230718141304.1032-11-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2023-07-20 10:03:00 +02:00
Takashi Iwai
b1e055f676 ALSA: control: Introduce unlocked version for snd_ctl_find_*() helpers
For reducing the unnecessary use of controls_rwsem in the drivers,
this patch adds a new variant for snd_ctl_find_*() helpers:
snd_ctl_find_id_locked() and snd_ctl_find_numid_locked() look for a
kctl element inside the card->controls_rwsem -- that is, doing the
very same as what snd_ctl_find_id() and snd_ctl_find_numid() did until
now.  snd_ctl_find_id() and snd_ctl_find_numid() remain same,
i.e. still unlocked version, but they will be switched to locked
version once after all callers are replaced.

The patch also replaces the calls of snd_ctl_find_id() and
snd_ctl_find_numid() in a few places; all of those are places where we
know that the functions are called properly with controls_rwsem held.
All others are without rwsem (although they should have been).

After this patch, we'll turn on the locking in snd_ctl_find_id() and
snd_ctl_find_numid() to be more race-free.

Link: https://lore.kernel.org/r/20230718141304.1032-10-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2023-07-20 10:03:00 +02:00
Takashi Iwai
6723670a48 ALSA: control: Make snd_ctl_find_id() argument const
The id object passed to snd_ctl_find_id() is only read, and we can
mark it with const gracefully.

Link: https://lore.kernel.org/r/20230718141304.1032-9-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2023-07-20 10:02:59 +02:00
Takashi Iwai
8320ba0ce5 ALSA: control: Add lockdep warning to internal functions
To assure the proper locking, add the lockdep check to
__snd_ctl_remove(), __snd_ctl_add_replace() and other internal
functions to handle user controls.

Link: https://lore.kernel.org/r/20230718141304.1032-6-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2023-07-20 10:01:40 +02:00
Takashi Iwai
192c4cccd0 ALSA: control: Take controls_rwsem lock in snd_ctl_remove()
So far, snd_ctl_remove() requires its caller to take
card->controls_rwsem manually before the call for avoiding possible
races.  However, many callers don't care and miss the locking.

Basically it's cumbersome and error-prone to enforce it to each
caller.  Moreover, card->controls_rwsem is a field that should be used
only by internal or proper helpers, and it's not to be touched at
random external places.

This patch is an attempt to make those calls more consistent: now
snd_ctl_remove() takes the card->controls_rwsem internally, just like
other API functions for kctls.  Since a few callers already take the
controls_rwsem locks, the patch removes those locks at the same time,
too.

Link: https://lore.kernel.org/r/20230718141304.1032-5-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2023-07-20 10:01:27 +02:00
Takashi Iwai
d4e99962d1 ALSA: control: Take card->controls_rwsem in snd_ctl_rename()
snd_ctl_rename() expects that card->controls_rwsem is held in the
caller side for avoiding possible races, but actually no one really
did that.  It's likely because this operation is done usually only at
the device initialization where no race can happen.  But, it's still
safer to take a lock, so we just take the lock inside snd_ctl_rename()
like most of other API functions do.

Link: https://lore.kernel.org/r/20230718141304.1032-2-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2023-07-20 10:00:02 +02:00
Takashi Iwai
306f3f78a5 ALSA: control: Keep the previous numid at snd_ctl_rename_id()
We don't need to change the numid at each time snd_ctl_rename_id() is
called, as the control element size itself doesn't change.  Let's keep
the previous numid value.

Along with it, add a note about calling this function only in the
card init phase.

Reviewed-by: Jaroslav Kysela <perex@perex.cz>
Link: https://lore.kernel.org/r/20230606094035.14808-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2023-06-06 14:34:30 +02:00
Clement Lecigne
56b88b5056 ALSA: pcm: Move rwsem lock inside snd_ctl_elem_read to prevent UAF
Takes rwsem lock inside snd_ctl_elem_read instead of snd_ctl_elem_read_user
like it was done for write in commit 1fa4445f9a ("ALSA: control - introduce
snd_ctl_notify_one() helper"). Doing this way we are also fixing the following
locking issue happening in the compat path which can be easily triggered and
turned into an use-after-free.

64-bits:
snd_ctl_ioctl
  snd_ctl_elem_read_user
    [takes controls_rwsem]
    snd_ctl_elem_read [lock properly held, all good]
    [drops controls_rwsem]

32-bits:
snd_ctl_ioctl_compat
  snd_ctl_elem_write_read_compat
    ctl_elem_write_read
      snd_ctl_elem_read [missing lock, not good]

CVE-2023-0266 was assigned for this issue.

Cc: stable@kernel.org # 5.13+
Signed-off-by: Clement Lecigne <clecigne@google.com>
Reviewed-by: Jaroslav Kysela <perex@perex.cz>
Link: https://lore.kernel.org/r/20230113120745.25464-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2023-01-13 14:15:26 +01:00
Maciej S. Szmigiero
966f015fe4 ALSA: control: add snd_ctl_rename()
Add a snd_ctl_rename() function that takes care of updating the control
hash entries for callers that already have the relevant struct snd_kcontrol
at hand and hold the control write lock (or simply haven't registered the
card yet).

Fixes: c27e1efb61 ("ALSA: control: Use xarray for faster lookups")
Cc: stable@vger.kernel.org
Signed-off-by: Maciej S. Szmigiero <maciej.szmigiero@oracle.com>
Link: https://lore.kernel.org/r/4170b71117ea81357a4f7eb8410f7cde20836c70.1666296963.git.maciej.szmigiero@oracle.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2022-10-21 08:17:08 +02:00
Dan Carpenter
5934d9a038 ALSA: control: Re-order bounds checking in get_ctl_id_hash()
These two checks are in the reverse order so it might read one element
beyond the end of the array.  First check if the "i" is within bounds
before using it.

Fixes: 6ab55ec0a9 ("ALSA: control: Fix an out-of-bounds bug in get_ctl_id_hash()")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/r/YwjgNh/gkG1hH7po@kili
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2022-08-26 17:17:22 +02:00
Zheyu Ma
6ab55ec0a9 ALSA: control: Fix an out-of-bounds bug in get_ctl_id_hash()
Since the user can control the arguments provided to the kernel by the
ioctl() system call, an out-of-bounds bug occurs when the 'id->name'
provided by the user does not end with '\0'.

The following log can reveal it:

[    10.002313] BUG: KASAN: stack-out-of-bounds in snd_ctl_find_id+0x36c/0x3a0
[    10.002895] Read of size 1 at addr ffff888109f5fe28 by task snd/439
[    10.004934] Call Trace:
[    10.007140]  snd_ctl_find_id+0x36c/0x3a0
[    10.007489]  snd_ctl_ioctl+0x6cf/0x10e0

Fix this by checking the bound of 'id->name' in the loop.

Fixes: c27e1efb61 ("ALSA: control: Use xarray for faster lookups")
Signed-off-by: Zheyu Ma <zheyuma97@gmail.com>
Link: https://lore.kernel.org/r/20220824081654.3767739-1-zheyuma97@gmail.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2022-08-24 11:41:53 +02:00
Takashi Iwai
4a971e84a7 ALSA: control: Use deferred fasync helper
For avoiding the potential deadlock via kill_fasync() call, use the
new fasync helpers to defer the invocation from the control API.  Note
that it's merely a workaround.

Another note: although we haven't received reports about the deadlock
with the control API, the deadlock is still potentially possible, and
it's better to align the behavior with other core APIs (PCM and
timer); so let's move altogether.

Link: https://lore.kernel.org/r/20220728125945.29533-5-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2022-07-29 12:57:12 +02:00
Takashi Iwai
e8406ebc37 ALSA: control: Fix missing return value comments for kernel docs
Each kernel doc comment expects the definition of the return value in
proper format.  This patch adds or fixes the missing entries for
control API.

Link: https://lore.kernel.org/r/20220713104759.4365-6-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2022-07-13 13:42:37 +02:00
Takashi Iwai
f5e829f92a ALSA: control: Add input validation
This patch adds a new feature to enable the validation of input data
to control elements in the ALSA core side.  When
CONFIG_SND_CTL_INPUT_VALIDATION is set, ALSA core verifies whether the
each input value via control API is in the defined ranges, also checks
whether it's aligned to the defined steps.  If an invalid value is
detected, ALSA core returns -EINVAL error immediately without passing
further to the driver's callback.  So this is a kind of hardening for
(badly written) drivers that have no proper error checks, at the cost
of a slight performance overhead.

Technically seen, this reuses a part of the existing validation code
for CONFIG_SND_CTL_DEBUG case with a slight modification to suppress
error prints for the input validation.

Link: https://lore.kernel.org/r/20220609120219.3937-5-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2022-06-15 07:45:28 +02:00
Takashi Iwai
4e54316ad2 ALSA: control: Drop superfluous ifdef CONFIG_SND_CTL_DEBUG
Compilers should be smart enough to optimize out the dead functions,
so we don't need to define ugly dummy functions with ifdef.

Link: https://lore.kernel.org/r/20220609120219.3937-4-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2022-06-15 07:45:28 +02:00
Takashi Iwai
1b7ec5143c ALSA: control: Rename CONFIG_SND_CTL_VALIDATION to CONFIG_SND_CTL_DEBUG
The purpose of CONFIG_SND_CTL_VALIDATION is rather to enable the
debugging feature for the control API.  The validation is only a part
of it.  Let's rename it to be more explicit and intuitive.

While we're at it, let's advertise, give more comment to recommend
this feature for development in the kconfig help text.

Link: https://lore.kernel.org/r/20220609120219.3937-3-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2022-06-15 07:45:27 +02:00
Takashi Iwai
c27e1efb61 ALSA: control: Use xarray for faster lookups
The control elements are managed in a single linked list and we
traverse the whole list for matching each numid or ctl id per every
inquiry of a control element.  This is OK-ish for a small number of
elements but obviously it doesn't scale.  Especially the matching with
the ctl id takes time because it checks each field of the snd_ctl_id
element, e.g. the name string is matched with strcmp().

This patch adds the hash tables with Xarray for improving the lookup
speed of a control element.  There are two xarray tables added to the
card; one for numid and another for ctl id.  For the numid, we use the
numid as the index, while for the ctl id, we calculate a hash key.

The lookup is done via a single xa_load() execution.  As long as the
given control element is found on the Xarray table, that's fine, we
can give back a quick lookup result.  The problem is when no entry
hits on the table, and for this case, we have a slight optimization.
Namely, the driver checks whether we had a collision on Xarray table,
and do a fallback search (linear lookup of the full entries) only if a
hash key collision happened beforehand.
So, in theory, the inquiry for a non-existing element might take still
time even with this patch in a worst case, but this must be pretty
rare.

The feature is enabled via CONFIG_SND_CTL_FAST_LOOKUP, which is turned
on as default.  For simplicity, the option can be turned off only when
CONFIG_EXPERT is set ("You are expert? Then you manage 1000 knobs").

Link: https://lore.kernel.org/r/20211028130027.18764-1-tiwai@suse.de
Link: https://lore.kernel.org/r/20220609180504.775-1-tiwai@suse.de
Link: https://lore.kernel.org/all/cover.1653813866.git.quic_rbankapu@quicinc.com/
Link: https://lore.kernel.org/r/20220610064537.18660-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2022-06-15 07:44:55 +02:00
Takashi Iwai
968bb2baec ALSA: control: Minor optimization for SNDRV_CTL_IOCTL_POWER_STATE
Long long time ago, before the proper PM framework was introduced, it
was still possible to reach SNDRV_CTL_IOCTL_POWER ioctl during the
power off state.  This ioctl existed as a main control for the suspend
resume state in the past, but the feature was already dropped along
with the standard PM framework.  Now the read part,
SNDRV_IOCTL_POWER_STATE ioctl, returns practically always D0, and we
can do some minor optimization there.

Reviewed-by: Jaroslav Kysela <perex@perex.cz>
Link: https://lore.kernel.org/r/20210523090920.15345-5-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2021-05-25 08:49:06 +02:00
Takashi Iwai
73063cd323 ALSA: control: Drop superfluous snd_power_wait() calls
Now we have more fine-grained power controls in each kcontrol ops, the
coarse checks of snd_power_wait() in a few control ioctls became
superfluous.  Let's drop them.

Reviewed-by: Jaroslav Kysela <perex@perex.cz>
Link: https://lore.kernel.org/r/20210523090920.15345-4-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2021-05-25 08:48:49 +02:00
Takashi Iwai
e94fdbd7b2 ALSA: control: Track in-flight control read/write/tlv accesses
Although the power state check is performed in various places (e.g. at
the entrance of quite a few ioctls), there can be still some pending
tasks that already went into the ioctl handler or other ops, and those
may access the hardware even after the power state check.  For
example, kcontrol access ioctl paths that call info/get/put callbacks
may update the hardware registers.  If a system wants to assure the
free from such hw access (like the case of PCI rescan feature we're
going to implement in future), this situation must be avoided, and we
have to sync such in-flight tasks finishing beforehand.

For that purpose, this patch introduces a few new things in core code:
- A refcount, power_ref, and a wait queue, power_ref_sleep, to the
  card object
- A few new helpers, snd_power_ref(), snd_power_unref(),
  snd_power_ref_and_wait(), and snd_power_sync_ref()

In the code paths that call kctl info/read/write/tlv ops, we check the
power state with the newly introduced snd_power_ref_and_wait().  This
function also takes the card.power_ref refcount for tracking this
in-flight task.  Once after the access finishes, snd_power_unref() is
called to released the refcount in return.  So the driver can sync via
snd_power_sync_ref() assuring that all in-flight tasks have been
finished.

As of this patch, snd_power_sync_ref() is called only at
snd_card_disconnect(), but it'll be used in other places in future.

Note that atomic_t is used for power_ref intentionally instead of
refcount_t.  It's because of the design of refcount_t type; refcount_t
cannot be zero-based, and it cannot do dec_and_test() call for
multiple times, hence it's not suitable for our purpose.

Also, this patch changes snd_power_wait() to accept only
SNDRV_CTL_POWER_D0, which is the only value that makes sense.
In later patch, the snd_power_wait() calls will be cleaned up.

Reviewed-by: Jaroslav Kysela <perex@perex.cz>
Link: https://lore.kernel.org/r/20210523090920.15345-3-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2021-05-25 08:48:28 +02:00
Takashi Iwai
998f26f47e ALSA: control: Fix racy management of user ctl memory size account
We've got a report about the possible race in the user control element
counts (card->user_ctl_count), and it was confirmed that the race
wasn't serious in the old code up to 5.12.  There, the value
modification itself was exclusive and protected via a write semaphore,
hence it's at most concurrent reads and evaluations before the
increment.  Since it's only about the soft-limit to avoid the
exhausting memory usage, one-off isn't a big problem at all.

Meanwhile, the relevant code has been largely modified recently, and
now card->user_ctl_count was replaced with card->user_ctl_alloc_size,
and a few more places were added to access this field.  And, in this
new code, it turned out to be more serious: the modifications are
scattered in various places, and a few of them are without protection.
It implies that it may lead to an inconsistent value by racy
accesses.

For addressing it, this patch extends the range covered by the
card->controls_rwsem write lock at snd_ctl_elem_add() so that the all
code paths that modify and refer to card->user_ctl_alloc_size are
protected by the rwsem properly.

The patch adds also comments in a couple of functions to indicate that
they are under the rwsem lock.

Fixes: 66c6d1ef86 ("ALSA: control: Add memory consumption limit to user controls")
Link: https://lore.kernel.org/r/FEEBF384-44BE-42CF-8FB3-93470933F64F@purdue.edu
Link: https://lore.kernel.org/r/20210415131856.13113-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2021-04-16 09:57:49 +02:00
Takashi Sakamoto
66c6d1ef86 ALSA: control: Add memory consumption limit to user controls
ALSA control interface allows users to add arbitrary control elements
(called "user controls" or "user elements"), and its resource usage is
limited just by the max number of control sets (currently 32).  This
limit, however, is quite loose: each allocation of control set may
have 1028 elements, and each element may have up to 512 bytes (ILP32) or
1024 bytes (LP64) of value data. Moreover, each control set may contain
the enum strings and TLV data, which can be up to 64kB and 128kB,
respectively.  Totally, the whole memory consumption may go over 38MB --
it's quite large, and we'd rather like to reduce the size.

OTOH, there have been other requests even to increase the max number
of user elements; e.g. ALSA firewire stack require the more user
controls, hence we want to raise the bar, too.

For satisfying both requirements, this patch changes the management of
user controls: instead of setting the upper limit of the number of
user controls, we check the actual memory allocation size and set the
upper limit of the total allocation in bytes.  As long as the memory
consumption stays below the limit, more user controls are allowed than
the current limit 32. At the same time, we set the lower limit (8MB)
as default than the current theoretical limit, in order to lower the
risk of DoS.

As a compromise for lowering the default limit, now the actual memory
limit is defined as a module option, 'max_user_ctl_alloc_size', so that
user can increase/decrease the limit if really needed, too.

Link: https://lore.kernel.org/r/s5htur3zl5e.wl-tiwai@suse.de
Co-developed-by: Takashi Iwai <tiwai@suse.de>
Reviewed-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Tested-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Link: https://lore.kernel.org/r/20210408103149.40357-1-o-takashi@sakamocchi.jp
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2021-04-08 13:31:03 +02:00
Jaroslav Kysela
016c20506d ALSA: control - add the missing prev_lops2 initialization
As static analysis reported, the prev_lops2 should contain
the previous lops2 pointer in snd_ctl_disconnect_layer().

Link: https://lore.kernel.org/alsa-devel/96e9bd5c-c8db-0db8-b393-fbf4a047dc80@canonical.com/
Fixes: 3f0638a033 ("ALSA: control - add layer registration routines")
Signed-off-by: Jaroslav Kysela <perex@perex.cz>
Link: https://lore.kernel.org/r/20210331180702.663489-1-perex@perex.cz
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2021-04-01 10:03:59 +02:00
Jaroslav Kysela
22d8de62f1 ALSA: control - add generic LED trigger module as the new control layer
The recent laptops have usually two LEDs assigned to reflect
the speaker and microphone mute state. This implementation
adds a tiny layer on top of the control API which calculates
the state for those LEDs using the driver callbacks.

Two new access flags are introduced to describe the controls
which affects the audio path settings (an easy code change
for drivers).

The LED resource can be shared with multiple sound cards with
this code. The user space controls may be added to the state
chain on demand, too.

This code should replace the LED code in the HDA driver and
add a possibility to easy extend the other drivers (ASoC
codecs etc.).

Signed-off-by: Jaroslav Kysela <perex@perex.cz>
Link: https://lore.kernel.org/r/20210317172945.842280-4-perex@perex.cz
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2021-03-30 15:33:58 +02:00
Jaroslav Kysela
3f0638a033 ALSA: control - add layer registration routines
The layer registration allows to handle an extra functionality
on top of the control API. It can be used for the audio
LED control for example.

Signed-off-by: Jaroslav Kysela <perex@perex.cz>
Link: https://lore.kernel.org/r/20210317172945.842280-3-perex@perex.cz
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2021-03-30 15:33:13 +02:00
Jaroslav Kysela
1fa4445f9a ALSA: control - introduce snd_ctl_notify_one() helper
This helper is required for the following generic LED mute
patch. The helper also simplifies some other functions.

Signed-off-by: Jaroslav Kysela <perex@perex.cz>
Link: https://lore.kernel.org/r/20210317172945.842280-2-perex@perex.cz
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2021-03-30 15:33:03 +02:00
Joe Perches
75b1a8f9d6 ALSA: Convert strlcpy to strscpy when return value is unused
strlcpy is deprecated.  see: Documentation/process/deprecated.rst

Change the calls that do not use the strlcpy return value to the
preferred strscpy.

Done with cocci script:

@@
expression e1, e2, e3;
@@

-	strlcpy(
+	strscpy(
	e1, e2, e3);

This cocci script leaves the instances where the return value is
used unchanged.

After this patch, sound/ has 3 uses of strlcpy() that need to be
manually inspected for conversion and changed one day.

$ git grep -w strlcpy sound/
sound/usb/card.c:               len = strlcpy(card->longname, s, sizeof(card->longname));
sound/usb/mixer.c:      return strlcpy(buf, p->name, buflen);
sound/usb/mixer.c:                      return strlcpy(buf, p->names[index], buflen);

Miscellenea:

o Remove trailing whitespace in conversion of sound/core/hwdep.c

Link: https://lore.kernel.org/lkml/CAHk-=wgfRnXz0W3D37d01q3JFkr_i_uTL=V6A6G1oUZcprmknw@mail.gmail.com/

Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/22b393d1790bb268769d0bab7bacf0866dcb0c14.camel@perches.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2021-01-08 09:30:05 +01:00
Lars-Peter Clausen
afcfbcb39f ALSA: core: Use DIV_ROUND_UP() instead of open-coding it
Use DIV_ROUND_UP() instead of open-coding it. This documents intent
and makes it more clear what is going on for the casual reviewer.

Generated using the following the Coccinelle semantic patch.

// <smpl>
@@
expression x, y;
@@
-(((x) + (y) - 1) / (y))
+DIV_ROUND_UP(x, y)
// </smpl>

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Link: https://lore.kernel.org/r/20201223172229.781-1-lars@metafoo.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2020-12-25 09:11:46 +01:00
Takashi Sakamoto
95a793c3bc ALSA: ctl: fix error path at adding user-defined element set
When processing request to add/replace user-defined element set, check
of given element identifier and decision of numeric identifier is done
in "__snd_ctl_add_replace()" helper function. When the result of check
is wrong, the helper function returns error code. The error code shall
be returned to userspace application.

Current implementation includes bug to return zero to userspace application
regardless of the result. This commit fixes the bug.

Cc: <stable@vger.kernel.org>
Fixes: e1a7bfe380 ("ALSA: control: Fix race between adding and removing a user element")
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Link: https://lore.kernel.org/r/20201113092043.16148-1-o-takashi@sakamocchi.jp
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2020-11-13 11:33:55 +01:00
Mauro Carvalho Chehab
f7b6603c66 ALSA: fix kernel-doc markups
Kernel-doc markups should use this format:
        identifier - description

There is a common comment marked, instead, with kernel-doc
notation.

Some identifiers have different names between their prototypes
and the kernel-doc markup.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Acked-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/535182d6f55d7a7de293dda9676df68f5f60afc6.1603469755.git.mchehab+huawei@kernel.org
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2020-10-26 15:26:31 +01:00
Takashi Iwai
6564d0ad67 ALSA: ctl: Workaround for lockdep warning wrt card->ctl_files_rwlock
The recent change in lockdep for read lock caused the deadlock
warnings in ALSA control code which uses the read_lock() for
notification and else while write_lock_irqsave() is used for adding
and removing the list entry.  Although a deadlock would practically
never hit in a real usage (the addition and the deletion can't happen
with the notification), it's better to fix the read_lock() usage in a
semantically correct way.

This patch replaces the read_lock() calls with read_lock_irqsave()
version for avoiding a reported deadlock.  The notification code path
takes the irq disablement in anyway, and other code paths are very
short execution, hence there shouldn't be any big performance hit by
this change.

Fixes: e918188611 ("locking: More accurate annotations for read_lock()")
Reported-by: syzbot+561a74f84100162990b2@syzkaller.appspotmail.com
Link: https://lore.kernel.org/r/20200922084953.29018-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2020-09-22 11:07:10 +02:00
Arnd Bergmann
18d122c028 ALSA: compat_ioctl: avoid compat_alloc_user_space
Using compat_alloc_user_space() tends to add complexity
to the ioctl handling, so I am trying to remove it everywhere.

The two callers in sound/core can rewritten to just call
the same code that operates on a kernel pointer as the
native handler.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/20200918095642.1446243-1-arnd@arndb.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2020-09-21 10:37:07 +02:00
Dan Carpenter
3b2549a374 ALSA: control: potential uninitialized return value
Smatch complains that "ret" might be uninitialized.

Fixes: fbd3eb7f66 ("ALSA: control: Add verification for kctl accesses")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/r/20200108053706.h3hcnvmnf62wkjac@kili.mountain
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2020-01-08 07:20:28 +01:00
Takashi Iwai
fbd3eb7f66 ALSA: control: Add verification for kctl accesses
The current implementation of ALSA control API fully relies on the
callbacks of each driver, and there is no verification of the values
passed via API.  This patch is an attempt to improve the situation
slightly by adding the validation code for the values stored via info
and get callbacks.

The patch adds a new kconfig, CONFIG_SND_CTL_VALIDATION.  It depends
on CONFIG_SND_DEBUG and off as default since the validation would
require a slight overhead including the additional call of info
callback at each get callback invocation.

When this config is enabled, the values stored by each info callback
invocation are verified, namely:
- Whether the info type is valid
- Whether the number of enum items is non-zero
- Whether the given info count is within the allowed boundary

Similarly, the values stored at each get callback are verified as
well:
- Whether the values are within the given range
- Whether the values are aligned with the given step
- Whether any further changes are seen in the data array over the
  given info count

The last point helps identifying a possibly invalid data type access,
typically a case where the info callback declares the type being
SNDRV_CTL_ELEM_TYPE_ENUMERATED while the get/put callbacks store
the values in value.integer.value[] array.

When a validation fails, the ALSA core logs an error message including
the device and the control ID, and the API call also returns an
error.  So, with the new validation turned on, the driver behavior
difference may be visible on user-space, too -- it's intentional,
though, so that we can catch an error more clearly.

The patch also introduces a new ctl access type,
SNDRV_CTL_ELEM_ACCESS_SKIP_CHECK.  A driver may pass this flag with
other access bits to indicate that the ctl element won't be verified.
It's useful when a driver code is specially written to access the data
greater than info->count size by some reason.  For example, this flag
is actually set now in HD-audio HDMI codec driver which needs to clear
the data array in the case of the disconnected monitor.

Also, the PCM channel-map helper code is slightly modified to avoid
the false-positive hit by this validation code, too.

Link: https://lore.kernel.org/r/20200104083556.27789-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2020-01-04 09:37:59 +01:00