ALSA: Replace snd_malloc_pages() and snd_free_pages() with standard helpers, take#2

snd_malloc_pages() and snd_free_pages() are merely thin wrappers of
the standard page allocator / free functions.

ALSA: Replace snd_malloc_pages() and snd_free_pages() with standard helpers, take#2

snd_malloc_pages() and snd_free_pages() are merely thin wrappers of
the standard page allocator / free functions. Even the arguments are
compatible with some standard helpers, so there is little merit of
keeping these wrappers.

This patch replaces the all existing callers of snd_malloc_pages() and
snd_free_pages() with the direct calls of the standard helper
functions. In this version, we use a recently introduced one,
alloc_pages_exact(), which suits better than the old
snd_malloc_pages() implementation for our purposes. Then we can avoid
the waste of pages by alignment to power-of-two.

Since alloc_pages_exact() does split pages, we need no longer
__GFP_COMP flag; or better to say, we must not pass __GFP_COMP to
alloc_pages_exact(). So the former unconditional addition of
__GFP_COMP flag in snd_malloc_pages() is dropped, as well as in most
other places.

Reviewed-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

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ALSA: pcm: Remove superfluous snd_info_register() calls

The calls of snd_info_register() are superfluous and should be avoided
at the procfs creation time. They are called at the end of the whole
i

ALSA: pcm: Remove superfluous snd_info_register() calls

The calls of snd_info_register() are superfluous and should be avoided
at the procfs creation time. They are called at the end of the whole
initialization via snd_card_register(). This patch drops such
superfluous calls, as well as cleaning up the calls of substream proc
entries with a common helper.

Reviewed-by: Jaroslav Kysela <perex@perex.cz>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

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ALSA: pcm: Simplify proc file destruction

The proc files are recursively freed by calling with the root
snd_info_entry object, so we don't have to keep each object for
releasing one by one. Move th

ALSA: pcm: Simplify proc file destruction

The proc files are recursively freed by calling with the root
snd_info_entry object, so we don't have to keep each object for
releasing one by one. Move the release of the PCM stream proc root at
the beginning, so that we can remove the redundant code and resource.

Signed-off-by: Takashi Iwai <tiwai@suse.de>

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ALSA: pcm: Unify snd_pcm_group initialization

There are multiple open codes that initialize the same object.
Create a common helper function instead.

Also, use kzalloc() to be safer at creating a g

ALSA: pcm: Unify snd_pcm_group initialization

There are multiple open codes that initialize the same object.
Create a common helper function instead.

Also, use kzalloc() to be safer at creating a group object, and move
the initialization out of the critical section.

Signed-off-by: Takashi Iwai <tiwai@suse.de>

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ALSA: pcm: Suspend streams globally via device type PM ops

Until now we rely on each driver calling snd_pcm_suspend*() explicitly
at its own PM handling. However, this can be done far more easily b

ALSA: pcm: Suspend streams globally via device type PM ops

Until now we rely on each driver calling snd_pcm_suspend*() explicitly
at its own PM handling. However, this can be done far more easily by
setting the PM ops to each actual snd_pcm device object.

This patch adds the device_type object for PCM stream and assigns to
each PCM stream object. The type contains only the PM ops for system
suspend; we don't need to deal with the resume in general.

The suspend hook simply calls snd_pcm_suspend_all() for the given PCM
streams. This implies that the PM order is correctly put, i.e. PCM is
suspended before the main (or codec) driver, which should be true in
general. If a special ordering is needed, you'd need to adjust the
device PM order manually later.

This patch introduces a new flag, snd_pcm.no_device_suspend, too.
With this flag set, the PCM device object won't invoke
snd_pcm_suspend_all() by itself. This is needed for ASoC who wants to
manage the PM call orders in its serialized way, and the flag is set
in soc_new_pcm() as default.

For the non-ASoC world, we can get rid of the manual snd_pcm_suspend
calls. This will be done in the later patches.

Reviewed-by: Jaroslav Kysela <perex@perex.cz>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

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ALSA: pcm: Fix potential Spectre v1 vulnerability

stream is indirectly controlled by user-space, hence leading to
a potential exploitation of the Spectre variant 1 vulnerability.

This issue was det

ALSA: pcm: Fix potential Spectre v1 vulnerability

stream is indirectly controlled by user-space, hence leading to
a potential exploitation of the Spectre variant 1 vulnerability.

This issue was detected with the help of Smatch:

sound/core/pcm.c:140 snd_pcm_control_ioctl() warn: potential spectre issue 'pcm->streams' [r] (local cap)

Fix this by sanitizing stream before using it to index pcm->streams

Notice that given that speculation windows are large, the policy is
to kill the speculation on the first load and not worry if it can be
completed with a dependent load/store [1].

[1] https://marc.info/?l=linux-kernel&m=152449131114778&w=2

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Cc: stable@vger.kernel.org
Signed-off-by: Takashi Iwai <tiwai@suse.de>

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ALSA: pcm: Use snd_pcm_stop_xrun() for xrun injection

Basically the xrun injection routine can simply call the standard
helper snd_pcm_stop_xrun(), but with one exception: it may be called
even when

ALSA: pcm: Use snd_pcm_stop_xrun() for xrun injection

Basically the xrun injection routine can simply call the standard
helper snd_pcm_stop_xrun(), but with one exception: it may be called
even when the stream is closed.

Make snd_pcm_stop_xrun() more robust and check the NULL runtime state,
and simplify xrun injection code by calling it.

Signed-off-by: Takashi Iwai <tiwai@suse.de>

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ALSA: pcm: trace XRUN event at injection, too

The PCM xrun injection triggers directly snd_pcm_stop() without the
standard xrun handler, hence it's not recorded on the event buffer.
Ditto for snd_pc

ALSA: pcm: trace XRUN event at injection, too

The PCM xrun injection triggers directly snd_pcm_stop() without the
standard xrun handler, hence it's not recorded on the event buffer.
Ditto for snd_pcm_stop_xrun() call and SNDRV_PCM_IOCTL_XRUN ioctl.
They are inconvenient from the debugging POV.

Let's make them to trigger XRUN via the standard helper more
consistently.

Signed-off-by: Takashi Iwai <tiwai@suse.de>

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sound: Use octal not symbolic permissions

Convert the S_<FOO> symbolic permissions to their octal equivalents as
using octal and not symbolic permissions is preferred by many as more
readable.

see:

sound: Use octal not symbolic permissions

Convert the S_<FOO> symbolic permissions to their octal equivalents as
using octal and not symbolic permissions is preferred by many as more
readable.

see: https://lkml.org/lkml/2016/8/2/1945

Done with automated conversion via:
$ ./scripts/checkpatch.pl -f --types=SYMBOLIC_PERMS --fix-inplace <files...>

Miscellanea:

o Wrapped one multi-line call to a single line

Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

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ALSA: pcm: Fix UAF at PCM release via PCM timer access

The PCM runtime object is created and freed dynamically at PCM stream
open / close time. This is tracked via substream->runtime, and it's
clea

ALSA: pcm: Fix UAF at PCM release via PCM timer access

The PCM runtime object is created and freed dynamically at PCM stream
open / close time. This is tracked via substream->runtime, and it's
cleared at snd_pcm_detach_substream().

The runtime object assignment is protected by PCM open_mutex, so for
all PCM operations, it's safely handled. However, each PCM substream
provides also an ALSA timer interface, and user-space can access to
this while closing a PCM substream. This may eventually lead to a
UAF, as snd_pcm_timer_resolution() tries to access the runtime while
clearing it in other side.

Fortunately, it's the only concurrent access from the PCM timer, and
it merely reads runtime->timer_resolution field. So, we can avoid the
race by reordering kfree() and wrapping the substream->runtime
clearance with the corresponding timer lock.

Reported-by: syzbot+8e62ff4e07aa2ce87826@syzkaller.appspotmail.com
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

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ALSA: pcm: prevent UAF in snd_pcm_info

When the device descriptor is closed, the `substream->runtime` pointer
is freed. But another thread may be in the ioctl handler, case
SNDRV_CTL_IOCTL_PCM_INFO.

ALSA: pcm: prevent UAF in snd_pcm_info

When the device descriptor is closed, the `substream->runtime` pointer
is freed. But another thread may be in the ioctl handler, case
SNDRV_CTL_IOCTL_PCM_INFO. This case calls snd_pcm_info_user() which
calls snd_pcm_info() which accesses the now freed `substream->runtime`.

Note: this fixes CVE-2017-0861

Signed-off-by: Robb Glasser <rglasser@google.com>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

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ALSA: pcm: Forcibly stop at disconnect callback

So far we assumed that each driver implements the hotplug PCM handling
properly, e.g. dealing with the pending PCM stream at disconnect
callback. But

ALSA: pcm: Forcibly stop at disconnect callback

So far we assumed that each driver implements the hotplug PCM handling
properly, e.g. dealing with the pending PCM stream at disconnect
callback. But most codes don't care, and it eventually leaves the PCM
stream inconsistent state when an abrupt disconnection like sysfs
unbind happens.

This patch is simple but a big-hammer solution: invoke snd_pcm_stop()
at the common PCM disconnect callback always when the stream is
running.

Tested-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

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ALSA: pcm: Don't call register and disconnect callbacks for internal PCM

The internal PCM (aka DPCM backend PCM) doesn't need any registration
procedure, thus currently we bail out immediately at de

ALSA: pcm: Don't call register and disconnect callbacks for internal PCM

The internal PCM (aka DPCM backend PCM) doesn't need any registration
procedure, thus currently we bail out immediately at dev_register
callback. Similarly, its counterpart, dev_disconnect callback, is
superfluous for the internal PCM. For simplifying and avoiding the
conflicting disconnect call for internal PCM objects, this patch drops
dev_register and dev_disconnect callbacks for the internal ops.

The only uncertain thing by this action is whether skipping the PCM
state change to SNDRV_PCM_STATE_DISCONNECT for the internal PCM is
mandatory. Looking through the current implementations, this doesn't
look so, hence dropping the whole dev_disconnect would make more
sense.

Tested-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

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ALSA: pcm: Correct broken procfs set up

The commit c8da9be4a75f ("ALSA: pcm: Adjust nine function calls
together with a variable assignment") contained a badly incorrect
conversion, a "status" PCM p

ALSA: pcm: Correct broken procfs set up

The commit c8da9be4a75f ("ALSA: pcm: Adjust nine function calls
together with a variable assignment") contained a badly incorrect
conversion, a "status" PCM procfs creation was replaced with the next
one. Luckily, this could be spotted easily by the kernel runtime
warning.

Fixes: c8da9be4a75f ("ALSA: pcm: Adjust nine function calls together...")
Reported-by: Fabio Estevam <fabio.estevam@nxp.com>
Tested-by: Fabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

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ALSA: pcm: Adjust nine function calls together with a variable assignment

The script "checkpatch.pl" pointed information out like the following.

ERROR: do not use assignment in if condition

Thus f

ALSA: pcm: Adjust nine function calls together with a variable assignment

The script "checkpatch.pl" pointed information out like the following.

ERROR: do not use assignment in if condition

Thus fix the affected source code places.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

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ALSA: pcm: Use common error handling code in _snd_pcm_new()

Add a jump target so that a bit of exception handling can be better reused
at the end of this function.

This issue was detected by using

ALSA: pcm: Use common error handling code in _snd_pcm_new()

Add a jump target so that a bit of exception handling can be better reused
at the end of this function.

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

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ALSA: pcm: constify attribute_group structures.

attribute_groups are not supposed to change at runtime. All functions
working with attribute_groups provided by <linux/device.h> work with const
attri

ALSA: pcm: constify attribute_group structures.

attribute_groups are not supposed to change at runtime. All functions
working with attribute_groups provided by <linux/device.h> work with const
attribute_group. So mark the non-const structs as const.

File size before:
text data bss dec hex filename
9781 240 8 10029 272d sound/core/pcm.o

File size After adding 'const':
text data bss dec hex filename
9813 176 8 9997 270d sound/core/pcm.o

Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

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ALSA: pcm: add local header file for snd-pcm module

Several files are used to construct PCM core module, a.k.a snd-pcm.
Although available APIs are described in 'include/sound/pcm.h', some of
them a

ALSA: pcm: add local header file for snd-pcm module

Several files are used to construct PCM core module, a.k.a snd-pcm.
Although available APIs are described in 'include/sound/pcm.h', some of
them are not exported as symbols in kernel space. Such APIs are just for
module local usage.

This commit adds module local header file and move some function prototypes
into it so that scopes of them are controlled properly and developers
get no confusion from unavailable symbols.

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

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ALSA: pcm: use "do {} while (0)" for empty macro

Recent compilers produce a harmless warning for the new pcm_call_notify()
macro when CONFIG_SND_PCM_OSS is disabled:

sound/core/pcm.c: In function '

ALSA: pcm: use "do {} while (0)" for empty macro

Recent compilers produce a harmless warning for the new pcm_call_notify()
macro when CONFIG_SND_PCM_OSS is disabled:

sound/core/pcm.c: In function 'snd_pcm_free':
sound/core/pcm.c:905:37: error: suggest braces around empty body in an 'if' statement [-Werror=empty-body]

This turns the empty macro into a 'do {} while (0)' statement to avoid
the warning.

Fixes: 58f30d650c7f ("ALSA: pcm: Build pcm notifier code conditionally")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

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ALSA: pcm: Build pcm notifier code conditionally

The PCM notifier code is used only by OSS emulation layer, so we can
build it conditionally for reducing the size.

Signed-off-by: Takashi Iwai <tiwa

ALSA: pcm: Build pcm notifier code conditionally

The PCM notifier code is used only by OSS emulation layer, so we can
build it conditionally for reducing the size.

Signed-off-by: Takashi Iwai <tiwai@suse.de>

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ALSA: pcm: Free chmap at PCM free callback, too

The chmap ctls assigned to PCM streams are freed in the PCM disconnect
callback. However, since the disconnect callback isn't called when
the card ge

ALSA: pcm: Free chmap at PCM free callback, too

The chmap ctls assigned to PCM streams are freed in the PCM disconnect
callback. However, since the disconnect callback isn't called when
the card gets freed before registering, the chmap ctls may still be
left assigned. They are eventually freed together with other ctls,
but it may cause an Oops at pcm_chmap_ctl_private_free(), as the
function refers to the assigned PCM stream, while the PCM objects have
been already freed beforehand.

The fix is to free the chmap ctls also at PCM free callback, not only
at PCM disconnect.

Reported-by: Laxminath Kasam <b_lkasam@codeaurora.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

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ALSA: pcm: remove structure member of 'struct snd_pcm_hwptr_log *' type because this structure had been removed

This structure was added by 4d96eb255c53 ('ALSA: pcm_lib - add possibility
to log last

ALSA: pcm: remove structure member of 'struct snd_pcm_hwptr_log *' type because this structure had been removed

This structure was added by 4d96eb255c53 ('ALSA: pcm_lib - add possibility
to log last 10 DMA ring buffer positions') to store PCM pointers
information of latest 10 pointer movements (=XRUN_LOG_CNT). When
CONFIG_SND_PCM_XRUN_DEBUG is configured, 'struct snd_pcm_runtime' has
'hwptr_log' member with a pointer to the structure. When calling
xrun_log() in pcm_lib.c, the structure was allocated to the pointer.
When calling snd_pcm_detach_substream() in pcm.c, the allocated pointer
is released.

In f5914908a5b7 ('ALSA: pcm: Replace PCM hwptr tracking with tracepoints'),
the pointer logging is replaced with using Linux Kernel Tracepoints. The
structure was also removed, while it's just declared. The member and kfree
still remains.

This commit removes the member and related codes. I think this was
overlooked because it brings no errors/warnings to C compilers.

Fixes: f5914908a5b7 ('ALSA: pcm: Replace PCM hwptr tracking with tracepoints')
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

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ALSA: pcm: Fix pcm_class sysfs output

The pcm_class sysfs of each PCM substream gives only "none" since the
recent code change to embed the struct device. Fix the code to point
directly to the embe

ALSA: pcm: Fix pcm_class sysfs output

The pcm_class sysfs of each PCM substream gives only "none" since the
recent code change to embed the struct device. Fix the code to point
directly to the embedded device object properly.

Fixes: ef46c7af93f9 ('ALSA: pcm: Embed struct device')
Cc: <stable@vger.kernel.org> # v4.0+
Signed-off-by: Takashi Iwai <tiwai@suse.de>

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ALSA: replace CONFIG_PROC_FS with CONFIG_SND_PROC_FS

We may disable proc fs only for sound part, to reduce ALSA
memory footprint. So add CONFIG_SND_PROC_FS and replace the
old CONFIG_PROC_FSs in als

ALSA: replace CONFIG_PROC_FS with CONFIG_SND_PROC_FS

We may disable proc fs only for sound part, to reduce ALSA
memory footprint. So add CONFIG_SND_PROC_FS and replace the
old CONFIG_PROC_FSs in alsa code.

With sound proc fs disabled, we can save about 9KB memory
size on X86_64 platform.

Signed-off-by: Jie Yang <yang.jie@intel.com>
Reviewed-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

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ALSA: core: Drop superfluous error/debug messages after malloc failures

The kernel memory allocators already report the errors when the
requested allocation fails, thus we don't need to warn it agai

ALSA: core: Drop superfluous error/debug messages after malloc failures

The kernel memory allocators already report the errors when the
requested allocation fails, thus we don't need to warn it again in
each caller side.

Signed-off-by: Takashi Iwai <tiwai@suse.de>

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