Commit Graph

1624 Commits

Author SHA1 Message Date
Takashi Iwai
9725752867 ALSA: info: Drop unused snd_info_entry.card field
It's referred only in snd_card_id_read() which can receive the card
object via private_data.

Reviewed-by: Jaroslav Kysela <perex@perex.cz>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2019-02-06 18:11:58 +01:00
Takashi Iwai
7453e1dafd ALSA: info: Add standard helpers for card proc file entries
Two new helper functions are added here for cleaning up the existing
lengthy calls.

Reviewed-by: Jaroslav Kysela <perex@perex.cz>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2019-02-06 18:11:55 +01:00
Takashi Iwai
4a471d7cc9 ALSA: compress: 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.

Reviewed-by: Jaroslav Kysela <perex@perex.cz>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2019-02-06 18:11:54 +01:00
Takashi Iwai
a8d149813b 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>
2019-02-06 18:11:54 +01:00
Takashi Iwai
348c5ad5d6 ALSA: info: Always register entries recursively
Make sure that all children entries are registered by a single call of
snd_info_register().  OTOH, don't register if a parent isn't
registered yet.

This allows us to create the whole procfs tree in a shot at the last
stage of card registration phase in a later patch.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2019-02-05 13:58:03 +01:00
Takashi Iwai
6ce1d63ed7 ALSA: core: Don't allow NULL device for memory allocation
Since we covered all callers with NULL device pointer, let's catch the
remaining calls with NULL and warn explicitly.

Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2019-02-05 11:05:26 +01:00
Guennadi Liakhovetski
515548fdd8 ALSA: pcm: remove a superfluous function declaration
Declaration of snd_pcm_drop() in sound/core/pcm_native.c is superfluous
since the function isn't called before being defined. Remove the
declaration.

Signed-off-by: Guennadi Liakhovetski <guennadi.liakhovetski@linux.intel.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2019-01-31 12:23:39 +01:00
Takashi Iwai
286406c2e1 Merge branch 'for-linus' into for-next
Pull 5.0 branch for further development of USB-audio quirks

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2019-01-29 11:07:48 +01:00
Takashi Iwai
e190161f96 ALSA: pcm: Fix tight loop of OSS capture stream
When the trigger=off is passed for a PCM OSS stream, it sets the
start_threshold of the given substream to the boundary size, so that
it won't be automatically started.  This can be problematic for a
capture stream, unfortunately, as detected by syzkaller.  The scenario
is like the following:

- In __snd_pcm_lib_xfer() that is invoked from snd_pcm_oss_read()
  loop, we have a check whether the stream was already started or the
  stream can be auto-started.
- The function at this check returns 0 with trigger=off since we
  explicitly disable the auto-start.
- The loop continues and repeats calling __snd_pcm_lib_xfer() tightly,
  which may lead to an RCU stall.

This patch fixes the bug by simply allowing the wait for non-started
stream in the case of OSS capture.  For native usages, it's supposed
to be done by the caller side (which is user-space), hence it returns
zero like before.

(In theory, __snd_pcm_lib_xfer() could wait even for the native API
 usage cases, too; but I'd like to stay in a safer side for not
 breaking the existing stuff for now.)

Reported-by: syzbot+fbe0496f92a0ce7b786c@syzkaller.appspotmail.com
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2019-01-25 19:45:46 +01:00
Takashi Iwai
315d9f1bee ALSA: pcm: Use the common error path in __snd_pcm_lib_xfer()
An open-coded error path in __snd_pcm_lib_xfer() can be replaced with
the simple goto to the common error path.  This also makes the error
handling more consistent, i.e. when some samples have been already
processed, return that size instead of the error code.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2019-01-25 17:31:59 +01:00
Takashi Iwai
205d6bcf9b Merge branch 'topic/pcm-lock-refactor' into for-next
Pull PCM lock refactoring.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2019-01-24 14:46:21 +01:00
Takashi Iwai
3a55437141 ALSA: proc: Avoid possible leaks of snd_info_entry objects
This patch changes the parent pointer assignment of snd_info_entry
object to be always non-NULL.  More specifically,check the parent
argument in snd_info_create_module_entry() & co, and assign
snd_proc_root if NULL is passed there.

This assures that the proc object is always freed when the root is
freed, so avoid possible memory leaks.  For example, some error paths
(e.g. snd_info_register() error at snd_minor_info_init()) may leave
snd_info_entry object although the proc file itself is freed.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2019-01-24 14:40:26 +01:00
Takashi Iwai
480e32ebd5 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>
2019-01-24 14:40:25 +01:00
Takashi Iwai
de89750c56 ALSA: pcm: Drop unused snd_pcm_substream.file field
It's assigned but nowhere used.  Let's remove it.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2019-01-24 14:40:25 +01:00
Takashi Iwai
ef2056b8f3 ALSA: pcm: Cleanup snd_pcm_stream_lock() & co
After the previous code refactoring, the PCM stream locking code
became nothing but the PCM group lock with self_group object.  Use the
existing helper function for simplifying the code.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2019-01-23 07:40:49 +01:00
Takashi Iwai
ecb41f0f44 ALSA: pcm: Remove down_write() hack for snd_pcm_link_rwsem
Remove the hackish down_write_nonfifo() that was introduced as a
workaround of rwsem deadlock.

It used to be a problem for non-atomic PCM streams that take the rwsem
for the locking and hit the high lock contention.  Since the current
PCM locking refactoring, we'll no longer hit it as the hot code-paths
don't take global locks.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2019-01-23 07:40:49 +01:00
Takashi Iwai
f57f3df03a ALSA: pcm: More fine-grained PCM link locking
We have currently two global locks, a rwlock and a rwsem, that are
used for managing linking the PCM streams.  Due to these global locks,
once when a linked stream is used, the lock granularity suffers a
lot.

This patch attempts to eliminate the former global lock for atomic
ops.  The latter rwsem needs remaining because of the loosy way of the
loop calls in snd_pcm_action_nonatomic(), as well as for avoiding the
deadlock at linking.  However, these are used far rarely, actually
only by two actions (prepare and  reset), where both are no timing
critical ones.  So this can be still seen as a good improvement.

The basic strategy to eliminate the rwlock is to assure group->lock at
adding or removing a stream to / from the group.  Since we already
takes the group lock whenever taking the all substream locks under the
group, this shouldn't be a big problem.  The reference to group
pointer in snd_pcm_substream object is protected by the stream lock
itself.

However, there are still pitfalls: a race window at re-locking and the
lifecycle of group object.  The former is a small race window for
dereferencing the substream group object opened while snd_pcm_action()
performs re-locking to avoid ABBA deadlocks.  This includes the unlink
of group during that window, too.  And the latter is the kfree
performed after all streams are removed from the group while it's
still dereferenced.

For addressing these corner cases, two new tricks are introduced:
- After re-locking, the group assigned to the stream is checked again;
  if the group is changed, we retry the whole procedure.
- Introduce a refcount to snd_pcm_group object, so that it's freed
  only when it's empty and really no one refers to it.

(Some readers might wonder why not RCU for the latter.  RCU in this
case would cost more than refcounting, unfortunately.  We take the
group lock sooner or later, hence the performance improvement by RCU
would be negligible.  Meanwhile, because we need to deal with
schedulable context depending on the pcm->nonatomic flag, it'll become
dynamic RCU/SRCU switch, and the grace period may become too long.)

Along with these changes, there are a significant amount of code
refactoring.  The complex group re-lock & ref code is factored out to
snd_pcm_stream_group_ref() function, for example.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2019-01-23 07:25:08 +01:00
Takashi Iwai
7df5a5f66b ALSA: pcm: Avoid confusing loop in snd_pcm_unlink()
The snd_pcm_group_for_each_entry() loop found in snd_pcm_unlink() is
only for taking the first list entry.  Use list_first_entry() to make
clearer.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2019-01-21 16:40:19 +01:00
Takashi Iwai
a41c4cb913 ALSA: pcm: Make PCM linked list consistent while re-grouping
Make a common helper to re-assign the PCM link using list_move() instead
of open code with manual list_del() and list_add_tail().  This assures
the consistency and we can get rid of snd_pcm_group.count field -- its
purpose is only to check whether the list is singular, and we can know
it by list_is_singular() call now.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2019-01-21 16:39:54 +01:00
Takashi Iwai
73365cb10b 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>
2019-01-21 16:39:35 +01:00
Takashi Iwai
d819fb21ee ALSA: pcm: Call snd_card_unref() inside in_pcm_file()
The snd_card_unref() call in snd_pcm_link() looks suspicious through a
quick glance, but it's a correct usage; this is needed just because
the file descriptor check in is_pcm_file() calls the helper
snd_lookup_minor_data() that keeps the card refcount.

Despite of the correctness, the code still looks confusing.
Basically, keeping the card ref for the whole code isn't needed
as fdget() blocks the release of the opened file.  Hence it's more
understandable if snd_card_unref() is moved into is_pcm_file(), then
the caller doesn't have to take care after the call.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2019-01-21 16:38:15 +01:00
Takashi Iwai
b3c4014c2b ASoC: Fixes for v5.0
Quite a big batch of fixes here.  There's a couple of things going on,
 the main one is that we found some issues with not deferring probe when
 we should, causing us to skip some driver initialization.  The fixes for
 this then in turn exposed some issues with how we were searching for
 components which had previously gone unnoticed due to the original
 issue.
 
 There's also been the normal driver specific stuff and there's been what
 looks like several batches of automated scanning for issues which have
 generated quite a large set of smaller fixes for potential crashes and
 missed error handling.
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Merge tag 'asoc-fix-v5.0-rc2' of https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into for-linus

ASoC: Fixes for v5.0

Quite a big batch of fixes here.  There's a couple of things going on,
the main one is that we found some issues with not deferring probe when
we should, causing us to skip some driver initialization.  The fixes for
this then in turn exposed some issues with how we were searching for
components which had previously gone unnoticed due to the original
issue.

There's also been the normal driver specific stuff and there's been what
looks like several batches of automated scanning for issues which have
generated quite a large set of smaller fixes for potential crashes and
missed error handling.
2019-01-18 15:17:17 +01:00
Takashi Iwai
ce7f93e2bd ALSA: pcm: Make snd_pcm_suspend() local static
snd_pcm_suspend() is no longer called from outside, so let's make it
local static.  Also drop a superfluous NULL check there.

Reviewed-by: Jaroslav Kysela <perex@perex.cz>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2019-01-15 17:48:23 +01:00
Takashi Iwai
3d21ef0b49 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>
2019-01-15 17:46:36 +01:00
Linus Torvalds
96d4f267e4 Remove 'type' argument from access_ok() function
Nobody has actually used the type (VERIFY_READ vs VERIFY_WRITE) argument
of the user address range verification function since we got rid of the
old racy i386-only code to walk page tables by hand.

It existed because the original 80386 would not honor the write protect
bit when in kernel mode, so you had to do COW by hand before doing any
user access.  But we haven't supported that in a long time, and these
days the 'type' argument is a purely historical artifact.

A discussion about extending 'user_access_begin()' to do the range
checking resulted this patch, because there is no way we're going to
move the old VERIFY_xyz interface to that model.  And it's best done at
the end of the merge window when I've done most of my merges, so let's
just get this done once and for all.

This patch was mostly done with a sed-script, with manual fix-ups for
the cases that weren't of the trivial 'access_ok(VERIFY_xyz' form.

There were a couple of notable cases:

 - csky still had the old "verify_area()" name as an alias.

 - the iter_iov code had magical hardcoded knowledge of the actual
   values of VERIFY_{READ,WRITE} (not that they mattered, since nothing
   really used it)

 - microblaze used the type argument for a debug printout

but other than those oddities this should be a total no-op patch.

I tried to fix up all architectures, did fairly extensive grepping for
access_ok() uses, and the changes are trivial, but I may have missed
something.  Any missed conversion should be trivially fixable, though.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-01-03 18:57:57 -08:00
Dan Carpenter
678e2b44c8
ALSA: compress: prevent potential divide by zero bugs
The problem is seen in the q6asm_dai_compr_set_params() function:

	ret = q6asm_map_memory_regions(dir, prtd->audio_client, prtd->phys,
				       (prtd->pcm_size / prtd->periods),
                                        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
				       prtd->periods);

In this code prtd->pcm_size is the buffer_size and prtd->periods comes
from params->buffer.fragments.  If we allow the number of fragments to
be zero then it results in a divide by zero bug.  One possible fix would
be to use prtd->pcm_count directly instead of using the division to
re-calculate it.  But I decided that it doesn't really make sense to
allow zero fragments.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-01-03 16:32:57 +00:00
Takashi Iwai
ed49e83919 ASoC: Updates for v4.21
Not much work on the core this time around but we've seen quite a bit of
 driver work, including on the generic DT drivers.  There's also a large
 part of the diff from a merge of the DaVinci and OMAP directories, along
 with some active development there:
 
  - Preparatory work from Morimoto-san for merging the audio-graph and
    audio-graph-scu cards.
  - A merge of the TI OMAP and DaVinci directories, the OMAP product line
    has been merged into the DaVinci product line so there is now a lot
    of IP sharing which meant that the split directories just got in the
    way.  This has pulled in a few architecture changes as well.
  - A big cleanup of the Maxim MAX9867 driver from Ladislav Michl.
  - Support for Asahi Kaesi AKM4118, AMD ACP3x, Intel platforms with
    RT5660, Meson AXG S/PDIF inputs, several Qualcomm IPs and Xilinx I2S
    controllers.
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Merge tag 'asoc-v4.21' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into for-next

ASoC: Updates for v4.21

Not much work on the core this time around but we've seen quite a bit of
driver work, including on the generic DT drivers.  There's also a large
part of the diff from a merge of the DaVinci and OMAP directories, along
with some active development there:

 - Preparatory work from Morimoto-san for merging the audio-graph and
   audio-graph-scu cards.
 - A merge of the TI OMAP and DaVinci directories, the OMAP product line
   has been merged into the DaVinci product line so there is now a lot
   of IP sharing which meant that the split directories just got in the
   way.  This has pulled in a few architecture changes as well.
 - A big cleanup of the Maxim MAX9867 driver from Ladislav Michl.
 - Support for Asahi Kaesi AKM4118, AMD ACP3x, Intel platforms with
   RT5660, Meson AXG S/PDIF inputs, several Qualcomm IPs and Xilinx I2S
   controllers.
2018-12-18 14:59:56 +01:00
Mark Brown
a7a850dba8
Merge branch 'asoc-4.21' into asoc-next 2018-12-18 12:23:59 +00:00
Srinivas Kandagatla
d00f749b00
ALSA: compress: make use of runtime buffer for copy
Default copy function uses kmalloc to allocate buffers, lets check
if the runtime buffers are setup before making this allocations.
This can be useful if the buffers are dma buffers.

Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Acked-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-12-14 12:43:45 +00:00
Gustavo A. R. Silva
94ffb030b6 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>
2018-12-13 09:14:33 +01:00
Takashi Iwai
2bff7e97eb Merge branch 'for-linus' into for-next
Back-merge for applying the more HD-audio quirks on top of the latest
code.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-12-07 11:40:04 +01:00
Chanho Min
b888a5f713 ALSA: pcm: Fix starvation on down_write_nonblock()
Commit 67ec1072b0 ("ALSA: pcm: Fix rwsem deadlock for non-atomic PCM
stream") fixes deadlock for non-atomic PCM stream. But, This patch
causes antother stuck.
If writer is RT thread and reader is a normal thread, the reader
thread will be difficult to get scheduled. It may not give chance to
release readlocks and writer gets stuck for a long time if they are
pinned to single cpu.

The deadlock described in the previous commit is because the linux
rwsem queues like a FIFO. So, we might need non-FIFO writelock, not
non-block one.

My suggestion is that the writer gives reader a chance to be scheduled
by using the minimum msleep() instaed of spinning without blocking by
writer. Also, The *_nonblock may be changed to *_nonfifo appropriately
to this concept.
In terms of performance, when trylock is failed, this minimum periodic
msleep will have the same performance as the tick-based
schedule()/wake_up_q().

[ Although this has a fairly high performance penalty, the relevant
  code path became already rare due to the previous commit ("ALSA:
  pcm: Call snd_pcm_unlink() conditionally at closing").  That is, now
  this unconditional msleep appears only when using linked streams,
  and this must be a rare case.  So we accept this as a quick
  workaround until finding a more suitable one -- tiwai ]

Fixes: 67ec1072b0 ("ALSA: pcm: Fix rwsem deadlock for non-atomic PCM stream")
Suggested-by: Wonmin Jung <wonmin.jung@lge.com>
Signed-off-by: Chanho Min <chanho.min@lge.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-11-29 08:15:19 +01:00
Takashi Iwai
b51abed835 ALSA: pcm: Call snd_pcm_unlink() conditionally at closing
Currently the PCM core calls snd_pcm_unlink() always unconditionally
at closing a stream.  However, since snd_pcm_unlink() invokes the
global rwsem down, the lock can be easily contended.  More badly, when
a thread runs in a high priority RT-FIFO, it may stall at spinning.

Basically the call of snd_pcm_unlink() is required only for the linked
streams that are already rare occasion.  For normal use cases, this
code path is fairly superfluous.

As an optimization (and also as a workaround for the RT problem
above in normal situations without linked streams), this patch adds a
check before calling snd_pcm_unlink() and calls it only when needed.

Reported-by: Chanho Min <chanho.min@lge.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-11-29 08:14:52 +01:00
Takashi Iwai
3103c08f96 ALSA: control: Consolidate helpers for adding and replacing ctl elements
Both snd_ctl_add() and snd_ctl_replace() process the things in a
fairly similar way, and indeed the most of the codes can be unified.

This patch is a refactoring to consolidate the both functions to call
a single helper with an extra "mode" argument.  There should be no
functional difference, except for one additional sanity check applied
now to snd_ctl_replace() (which was rather overlooking, IMO), too.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-11-24 20:04:10 +01:00
Takashi Iwai
e1a7bfe380 ALSA: control: Fix race between adding and removing a user element
The procedure for adding a user control element has some window opened
for race against the concurrent removal of a user element.  This was
caught by syzkaller, hitting a KASAN use-after-free error.

This patch addresses the bug by wrapping the whole procedure to add a
user control element with the card->controls_rwsem, instead of only
around the increment of card->user_ctl_count.

This required a slight code refactoring, too.  The function
snd_ctl_add() is split to two parts: a core function to add the
control element and a part calling it.  The former is called from the
function for adding a user control element inside the controls_rwsem.

One change to be noted is that snd_ctl_notify() for adding a control
element gets called inside the controls_rwsem as well while it was
called outside the rwsem.  But this should be OK, as snd_ctl_notify()
takes another (finer) rwlock instead of rwsem, and the call of
snd_ctl_notify() inside rwsem is already done in another code path.

Reported-by: syzbot+dc09047bce3820621ba2@syzkaller.appspotmail.com
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-11-24 19:57:51 +01:00
Takashi Iwai
65766ee0bf ALSA: oss: Use kvzalloc() for local buffer allocations
PCM OSS layer may allocate a few temporary buffers, one for the core
read/write and another for the conversions via plugins.  Currently
both are allocated via vmalloc().  But as the allocation size is
equivalent with the PCM period size, the required size might be quite
small, depending on the application.

This patch replaces these vmalloc() calls with kvzalloc() for covering
small period sizes better.  Also, we use "z"-alloc variant here for
addressing the possible uninitialized access reported by syzkaller.

Reported-by: syzbot+1cb36954e127c98dd037@syzkaller.appspotmail.com
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-11-09 14:12:04 +01:00
Takashi Iwai
e8c92251a8 ALSA: seq: oss: Use the standard fall-through annotation
As a preparatory patch for the upcoming -Wimplicit-fallthrough
compiler checks, replace with the standard "fall through" annotation.
Unfortunately gcc doesn't understand a chattier text.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-10-12 09:31:29 +02:00
Takashi Iwai
3c4cfa7bf6 ALSA: memalloc: Add fall-through annotation
As a preparatory patch for the upcoming -Wimplicit-fallthrough
compiler checks, add the "fall through" annotation in
snd_dma_alloc_pages().  Note that this seems necessary to be put
exactly before the next label, so it's outside the ifdef block.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-10-12 09:31:23 +02:00
Takashi Iwai
6aea5702e2 ALSA: rawmidi: A lightweight function to discard pending bytes
For discarding the pending bytes on rawmidi, we process with a loop of
snd_rawmidi_transmit() which is just a waste of CPU power.
Implement a lightweight API function to discard the pending bytes and
the proceed the ring buffer instantly, and use it instead of open
codes.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-10-04 20:13:17 +02:00
Ricardo Biehl Pasquali
64b6acf60b ALSA: pcm: Update hardware pointer before start capture
This ensures the transfer loop won't waste a run to read
the few frames (if any) between start and hw_ptr update.
It will wait for the next interrupt with wait_for_avail().

Signed-off-by: Ricardo Biehl Pasquali <pasqualirb@gmail.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-09-10 09:06:55 +02:00
Takashi Iwai
70f7922c25 Merge branch 'topic/pcm-indirect-fixes' into for-next
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-09-04 20:23:40 +02:00
Takashi Iwai
5a7b44a8df ALSA: rawmidi: Initialize allocated buffers
syzbot reported the uninitialized value exposure in certain situations
using virmidi loop.  It's likely a very small race at writing and
reading, and the influence is almost negligible.  But it's safer to
paper over this just by replacing the existing kvmalloc() with
kvzalloc().

Reported-by: syzbot+194dffdb8b22fc5d207a@syzkaller.appspotmail.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-09-03 15:16:43 +02:00
Takashi Iwai
42e748a0b3 ALSA: memalloc: Add non-cached buffer type
In some cases (mainly for x86), we need the DMA coherent buffer with
non-cached pages.  Although this has been done in each driver side
like HD-audio and intel8x0, it can be done cleaner in the core memory
allocator.

This patch adds the new types, SNDRV_DMA_TYPE_DEV_UC and
SNDRV_DMA_TYPE_DEV_UC_SG, for allocating such non-cached buffer
pages.  On non-x86 architectures, they work as same as the standard
SNDRV_DMA_TYPE_DEV and *_SG.

One additional change by this move is that we can assure to pass the
non-cached pgprot to the vmapped buffer, too.  It eventually fixes the
case like non-snoop mode without mmap access on HD-audio.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-08-28 13:56:47 +02:00
Takashi Iwai
28f3f4f685 ALSA: memalloc: Simplify snd_malloc_dev_pages() calls
snd_malloc_dev_pages() and snd_free_dev_pages() are local functions
and the parameters passed there are all contained in snd_dma_buffer
object.  As a code-simplification, pass snd_dma_buffer object and
assign the address there like other allocators do (except for
snd_malloc_pages() which is called from outside, hence we can't change
easily).

Only code refactoring, no functional changes.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-08-28 13:56:46 +02:00
Takashi Iwai
03486830c5 ALSA: memalloc: Don't align the size to power-of-two
The size passed to dma_alloc_coherent() doesn't have to be aligned
with power-of-two, rather it should be the raw size.  As a minor
optimization, remove the size adjustment in the current code.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-08-28 13:56:46 +02:00
Takashi Iwai
b8e131542b ALSA: seq: Do error checks at creating system ports
snd_seq_system_client_init() doesn't check the errors returned from
its port creations.  Let's do it properly and handle the error paths.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-08-28 12:52:02 +02:00
Dan Carpenter
c4f1957e14 ALSA: seq: add error check in snd_seq_system_client_init()
Static checkers complain that snd_seq_create_kernel_client() can return
-EBUSY here so we need to have some error handling.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-08-28 11:06:11 +02:00
Dan Carpenter
6f128fa41f ALSA: pcm: signedness bug in snd_pcm_plug_alloc()
The "frames" variable is unsigned so the error handling doesn't work
properly.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-08-27 11:28:40 +02:00
Ricardo Biehl Pasquali
62ba568f7a ALSA: pcm: Return 0 when size < start_threshold in capture
In __snd_pcm_lib_xfer(), when capture, if state is PREPARED
and size is less than start_threshold nothing can be done.
As there is no error, 0 is returned.

Signed-off-by: Ricardo Biehl Pasquali <pasqualirb@gmail.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-08-27 07:27:55 +02:00
Takashi Iwai
82fd4b05d7 ALSA: seq: virmidi: Fix discarding the unsubscribed output
The recent change to move the virmidi output processing to a work
slightly modified the code to discard the unsubscribed outputs so that
it works without a temporary buffer.  However, this is actually buggy,
and may spew a kernel warning due to the unexpected call of
snd_rawmidi_transmit_ack(), as triggered by syzbot.

This patch takes back to the original code in that part, use a
temporary buffer and simply repeat snd_rawmidi_transmit(), in order to
address the regression.

Fixes: f7debfe540 ("ALSA: seq: virmidi: Offload the output event processing")
Reported-by: syzbot+ec5f605c91812d200367@syzkaller.appspotmail.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-08-14 22:50:52 +02:00
Gustavo A. R. Silva
eb2caeb88c ALSA: seq_oss: Mark expected switch fall-through
In preparation to enabling -Wimplicit-fallthrough, mark switch cases
where we are expecting to fall through.

Warning level 2 was used: -Wimplicit-fallthrough=2

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-08-04 08:30:45 +02:00
Gustavo A. R. Silva
2f3b94e539 ALSA: seq: Mark expected switch fall-through
In preparation to enabling -Wimplicit-fallthrough, mark switch cases
where we are expecting to fall through.

Notice that in this particular case, I replaced the code comment with
a proper "fall through" annotation, which is what GCC is expecting
to find.

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-08-04 08:30:36 +02:00
Takashi Iwai
a640329989 ALSA: compress: Remove empty init and exit
For a sake of code simplification, remove the init and the exit
entries that do nothing.

Notes for readers: actually it's OK to remove *both* init and exit,
but not OK to remove the exit entry.  By removing only the exit while
keeping init, the module becomes permanently loaded; i.e. you cannot
unload it any longer!

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-08-03 16:11:23 +02:00
Takashi Iwai
93ce1b1296 ALSA: seq: Drop unused 64bit division macros
The old ugly macros remained in the code without usage.
Rip them off.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-08-01 22:54:37 +02:00
Takashi Iwai
04702e8d00 ALSA: seq: Use no intrruptible mutex_lock
All usages of mutex in ALSA sequencer core would take too long, hence
we don't have to care about the user interruption that makes things
complicated.  Let's replace them with simpler mutex_lock().

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-08-01 22:54:36 +02:00
Takashi Iwai
00976ad527 ALSA: seq: Fix leftovers at probe error path
The sequencer core module doesn't call some destructors in the error
path of the init code, which may leave some resources.

This patch mainly fix these leaks by calling the destructors
appropriately at alsa_seq_init().  Also the patch brings a few
cleanups along with it, namely:

- Expand the old "if ((err = xxx) < 0)" coding style
- Get rid of empty seq_queue_init() and its caller
- Change snd_seq_info_done() to void

Last but not least, a couple of functions lose __exit annotation since
they are called also in alsa_seq_init().

No functional changes but minor code cleanups.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-08-01 22:54:36 +02:00
Takashi Iwai
fc4bfd9a35 ALSA: seq: Remove dead codes
There are a few functions that have been commented out for ages.
And also there are functions that do nothing but placeholders.
Let's kill them.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-08-01 22:54:35 +02:00
Takashi Iwai
ef965ad5a7 ALSA: seq: Minor cleanup of MIDI event parser helpers
snd_midi_event_encode_byte() can never fail, and it can return rather
true/false.  Change the return type to bool, adjust the argument to
receive a MIDI byte as unsigned char, and adjust the comment
accordingly.  This allows callers to drop error checks, which
simplifies the code.

Meanwhile, snd_midi_event_encode() helper is used only in seq_midi.c,
and it can be better folded into it.  This will reduce the total
amount of lines in the end.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-08-01 22:54:35 +02:00
Gustavo A. R. Silva
5a6cd13d4f ALSA: pcm: Mark expected switch fall-through
In preparation to enabling -Wimplicit-fallthrough, mark switch cases
where we are expecting to fall through.

Addresses-Coverity-ID: 1357375 ("Missing break in switch")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-08-01 18:13:04 +02:00
Takashi Iwai
89b4ab213f ALSA: seq: virmidi: Use READ_ONCE/WRITE_ONCE() macros
The trigger flag in vmidi object can be referred in different contexts
concurrently, hence it's better to be put with READ_ONCE() and
WRITE_ONCE() macros to assure the accesses.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-07-30 14:52:30 +02:00
Takashi Iwai
f7debfe540 ALSA: seq: virmidi: Offload the output event processing
The virmidi sequencer stuff tries to translate the rawmidi bytes to
sequencer events and deliver the packets at trigger callback.  The
amount of the whole process of these translations and deliveries
depends on the incoming rawmidi bytes, and we have no limit for that;
this was the cause of a CPU soft lockup that had been reported and
fixed recently.

Although we've fixed the soft lockup by putting the temporary unlock
and cond_resched(), it's rather a quick band aid.  In this patch,
meanwhile, the event parsing and delivery process is offloaded to a
dedicated work, and the trigger callback just kicks it off.  It has
three merits, at least:

- The processing is always done in a sleepable context, which can
  assure the event delivery with non-atomic flag without hackish
  is_atomic() usage.

- Other relevant codes can be simplified, reducing the lines

- It makes me happier

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-07-30 14:51:51 +02:00
Takashi Iwai
16c796e8fa Merge branch 'for-linus' into topic/virmidi
Pull the latest ALSA sequencer fixes for the further development of
virmidi.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-07-29 22:39:29 +02:00
Takashi Iwai
f8b6c0cfbd ALSA: pcm: Fix sparse warning wrt PCM format type
The PCM format type is with __bitwise, hence it needs the explicit
cast with __force.  It's ugly, but there is a reason for that cost...

This fixes the sparse warning:
  sound/core/oss/pcm_oss.c:1854:55: warning: incorrect type in argument 1 (different base types)

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-07-27 09:05:27 +02:00
Takashi Iwai
50e9ffb199 ALSA: virmidi: Fix too long output trigger loop
The virmidi output trigger tries to parse the all available bytes and
process sequencer events as much as possible.  In a normal situation,
this is supposed to be relatively short, but a program may give a huge
buffer and it'll take a long time in a single spin lock, which may
eventually lead to a soft lockup.

This patch simply adds a workaround, a cond_resched() call in the loop
if applicable.  A better solution would be to move the event processor
into a work, but let's put a duct-tape quickly at first.

Reported-and-tested-by: Dae R. Jeong <threeearcat@gmail.com>
Reported-by: syzbot+619d9f40141d826b097e@syzkaller.appspotmail.com
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-07-27 08:59:25 +02:00
Takashi Iwai
191bb51e72 ALSA: pcm: Use standard lower_32_bits() and upper_32_bits()
Instead of open codes, use the standard macros for obtaining the lower
and upper 32bit values.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-07-26 08:32:31 +02:00
Takashi Iwai
a49a71f6e2 ALSA: seq: Fix poll() error return
The sanity checks in ALSA sequencer and OSS sequencer emulation codes
return falsely -ENXIO from poll callback.  They should be EPOLLERR
instead.

This was caught thanks to the recent change to the return value.

Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-07-26 08:23:26 +02:00
Takashi Iwai
dfef01e150 ALSA: memalloc: Don't exceed over the requested size
snd_dma_alloc_pages_fallback() tries to allocate pages again when the
allocation fails with reduced size.  But the first try actually
*increases* the size to power-of-two, which may give back a larger
chunk than the requested size.  This confuses the callers, e.g. sgbuf
assumes that the size is equal or less, and it may result in a bad
loop due to the underflow and eventually lead to Oops.

The code of this function seems incorrectly assuming the usage of
get_order().  We need to decrease at first, then align to
power-of-two.

Reported-and-tested-by: he, bo <bo.he@intel.com>
Reported-by: zhang jun <jun.zhang@intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-07-23 09:06:33 +02:00
Srikanth K H
d10ee9c542 ALSA: timer: catch invalid timer object creation
A timer object for the classes SNDRV_TIMER_CLASS_CARD and
SNDRV_TIMER_CLASS_PCM has to be associated with a card object, but we
have no check at creation time.  Such a timer object with NULL card
causes various unexpected problems, e.g. NULL dereference at reading
the sound timer proc file.

So as preventive measure while the creating the sound timer object is
created the card information availability is checked for the mentioned
entries and returned error if its NULL.

Signed-off-by: Srikanth K H <srikanth.h@samsung.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-07-22 10:42:41 +02:00
Takashi Iwai
ef4db239cd ALSA: rawmidi: Use kvmalloc() for buffers
The size of in-kernel rawmidi buffers may be big up to 1MB, and it can
be specified freely by user-space; which implies that user-space may
trigger kmalloc() errors frequently.

This patch replaces the buffer allocation via kvmalloc() for dealing
with bigger buffers gracefully.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-07-18 07:47:57 +02:00
Takashi Iwai
f5beb598b0 ALSA: rawmidi: Minor code refactoring
Unify a few open codes with helper functions to improve the
readability.  Minor behavior changes (rather fixes) are:
- runtime->drain clearance is done within lock
- active_sensing is updated before resizing buffer in
  SNDRV_RAWMIDI_IOCTL_PARAMS ioctl.
Other than that, simply code cleanups.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-07-17 23:07:29 +02:00
Takashi Iwai
7fdc9b0807 ALSA: rawmidi: Simplify error paths
Apply the standard idiom: rewrite the multiple unlocks in error paths
in the goto-error-and-single-unlock way.

Just a code refactoring, and no functional changes.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-07-17 22:48:38 +02:00
Takashi Iwai
5bed913972 ALSA: rawmidi: Tidy up coding styles
Just minor coding style fixes like removal of superfluous white space,
adding missing blank lines, etc.  No actual code changes at all.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-07-17 22:37:07 +02:00
Takashi Iwai
ed6b83d2d1 Merge branch 'for-linus' into for-next
Back-merge for further cleanup / improvements on rawmidi and HD-audio
stuff.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-07-17 22:27:03 +02:00
Takashi Iwai
39675f7a7c ALSA: rawmidi: Change resized buffers atomically
The SNDRV_RAWMIDI_IOCTL_PARAMS ioctl may resize the buffers and the
current code is racy.  For example, the sequencer client may write to
buffer while it being resized.

As a simple workaround, let's switch to the resized buffer inside the
stream runtime lock.

Reported-by: syzbot+52f83f0ea8df16932f7f@syzkaller.appspotmail.com
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-07-17 17:33:17 +02:00
Timo Wischer
ff2d6acdf6 ALSA: pcm: Fix snd_interval_refine first/last with open min/max
Without this commit the following intervals [x y), (x y) were be
replaced to (y-1 y) by snd_interval_refine_last(). This was also done
if y-1 is part of the previous interval.
With this changes it will be replaced with [y-1 y) in case of y-1 is
part of the previous interval. A similar behavior will be used for
snd_interval_refine_first().

This commit adapts the changes for alsa-lib of commit
9bb985c ("pcm: snd_interval_refine_first/last: exclude value only if
also excluded before")

Signed-off-by: Timo Wischer <twischer@de.adit-jv.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-07-11 08:49:59 +02:00
Liam Girdwood
d64c5cf8e8 ALSA: pcm: Allow drivers to set R/W wait time.
Currently ALSA core blocks userspace for about 10 seconds for PCM R/W IO.
This needs to be configurable for modern hardware like DSPs where no
pointer update in milliseconds can indicate terminal DSP errors.

Add a substream variable to set the wait time in ms. This allows userspace
and drivers to recover more quickly from terminal DSP errors.

Signed-off-by: Liam Girdwood <liam.r.girdwood@linux.intel.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-07-06 15:00:25 +02:00
Takashi Iwai
e647f5a5c5 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>
2018-07-04 15:34:59 +02:00
Takashi Iwai
9cd641ed31 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>
2018-07-04 15:34:57 +02:00
Takashi Iwai
c9a4c63888 ALSA: seq: Fix UBSAN warning at SNDRV_SEQ_IOCTL_QUERY_NEXT_CLIENT ioctl
The kernel may spew a WARNING with UBSAN undefined behavior at
handling ALSA sequencer ioctl SNDRV_SEQ_IOCTL_QUERY_NEXT_CLIENT:

UBSAN: Undefined behaviour in sound/core/seq/seq_clientmgr.c:2007:14
signed integer overflow:
2147483647 + 1 cannot be represented in type 'int'
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x122/0x1c8 lib/dump_stack.c:113
 ubsan_epilogue+0x12/0x86 lib/ubsan.c:159
 handle_overflow+0x1c2/0x21f lib/ubsan.c:190
  __ubsan_handle_add_overflow+0x2a/0x31 lib/ubsan.c:198
 snd_seq_ioctl_query_next_client+0x1ac/0x1d0 sound/core/seq/seq_clientmgr.c:2007
 snd_seq_ioctl+0x264/0x3d0 sound/core/seq/seq_clientmgr.c:2144
 ....

It happens only when INT_MAX is passed there, as we're incrementing it
unconditionally.  So the fix is trivial, check the value with
INT_MAX.  Although the bug itself is fairly harmless, it's better to
fix it so that fuzzers won't hit this again later.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=200211
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-06-25 11:18:04 +02:00
Takashi Iwai
b41f794f28 ALSA: timer: Fix UBSAN warning at SNDRV_TIMER_IOCTL_NEXT_DEVICE ioctl
The kernel may spew a WARNING about UBSAN undefined behavior at
handling ALSA timer ioctl SNDRV_TIMER_IOCTL_NEXT_DEVICE:

UBSAN: Undefined behaviour in sound/core/timer.c:1524:19
signed integer overflow:
2147483647 + 1 cannot be represented in type 'int'
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x122/0x1c8 lib/dump_stack.c:113
 ubsan_epilogue+0x12/0x86 lib/ubsan.c:159
 handle_overflow+0x1c2/0x21f lib/ubsan.c:190
 __ubsan_handle_add_overflow+0x2a/0x31 lib/ubsan.c:198
 snd_timer_user_next_device sound/core/timer.c:1524 [inline]
 __snd_timer_user_ioctl+0x204d/0x2520 sound/core/timer.c:1939
 snd_timer_user_ioctl+0x67/0x95 sound/core/timer.c:1994
 ....

It happens only when a value with INT_MAX is passed, as we're
incrementing it unconditionally.  So the fix is trivial, check the
value with INT_MAX.  Although the bug itself is fairly harmless, it's
better to fix it so that fuzzers won't hit this again later.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=200213
Reported-and-tested-by: Team OWL337 <icytxw@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-06-25 11:17:01 +02:00
Mauro Carvalho Chehab
5fb94e9ca3 docs: Fix some broken references
As we move stuff around, some doc references are broken. Fix some of
them via this script:
	./scripts/documentation-file-ref-check --fix

Manually checked if the produced result is valid, removing a few
false-positives.

Acked-by: Takashi Iwai <tiwai@suse.de>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Acked-by: Stephen Boyd <sboyd@kernel.org>
Acked-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Acked-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: Coly Li <colyli@suse.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Acked-by: Jonathan Corbet <corbet@lwn.net>
2018-06-15 18:10:01 -03:00
Kees Cook
42bc47b353 treewide: Use array_size() in vmalloc()
The vmalloc() function has no 2-factor argument form, so multiplication
factors need to be wrapped in array_size(). This patch replaces cases of:

        vmalloc(a * b)

with:
        vmalloc(array_size(a, b))

as well as handling cases of:

        vmalloc(a * b * c)

with:

        vmalloc(array3_size(a, b, c))

This does, however, attempt to ignore constant size factors like:

        vmalloc(4 * 1024)

though any constants defined via macros get caught up in the conversion.

Any factors with a sizeof() of "unsigned char", "char", and "u8" were
dropped, since they're redundant.

The Coccinelle script used for this was:

// Fix redundant parens around sizeof().
@@
type TYPE;
expression THING, E;
@@

(
  vmalloc(
-	(sizeof(TYPE)) * E
+	sizeof(TYPE) * E
  , ...)
|
  vmalloc(
-	(sizeof(THING)) * E
+	sizeof(THING) * E
  , ...)
)

// Drop single-byte sizes and redundant parens.
@@
expression COUNT;
typedef u8;
typedef __u8;
@@

(
  vmalloc(
-	sizeof(u8) * (COUNT)
+	COUNT
  , ...)
|
  vmalloc(
-	sizeof(__u8) * (COUNT)
+	COUNT
  , ...)
|
  vmalloc(
-	sizeof(char) * (COUNT)
+	COUNT
  , ...)
|
  vmalloc(
-	sizeof(unsigned char) * (COUNT)
+	COUNT
  , ...)
|
  vmalloc(
-	sizeof(u8) * COUNT
+	COUNT
  , ...)
|
  vmalloc(
-	sizeof(__u8) * COUNT
+	COUNT
  , ...)
|
  vmalloc(
-	sizeof(char) * COUNT
+	COUNT
  , ...)
|
  vmalloc(
-	sizeof(unsigned char) * COUNT
+	COUNT
  , ...)
)

// 2-factor product with sizeof(type/expression) and identifier or constant.
@@
type TYPE;
expression THING;
identifier COUNT_ID;
constant COUNT_CONST;
@@

(
  vmalloc(
-	sizeof(TYPE) * (COUNT_ID)
+	array_size(COUNT_ID, sizeof(TYPE))
  , ...)
|
  vmalloc(
-	sizeof(TYPE) * COUNT_ID
+	array_size(COUNT_ID, sizeof(TYPE))
  , ...)
|
  vmalloc(
-	sizeof(TYPE) * (COUNT_CONST)
+	array_size(COUNT_CONST, sizeof(TYPE))
  , ...)
|
  vmalloc(
-	sizeof(TYPE) * COUNT_CONST
+	array_size(COUNT_CONST, sizeof(TYPE))
  , ...)
|
  vmalloc(
-	sizeof(THING) * (COUNT_ID)
+	array_size(COUNT_ID, sizeof(THING))
  , ...)
|
  vmalloc(
-	sizeof(THING) * COUNT_ID
+	array_size(COUNT_ID, sizeof(THING))
  , ...)
|
  vmalloc(
-	sizeof(THING) * (COUNT_CONST)
+	array_size(COUNT_CONST, sizeof(THING))
  , ...)
|
  vmalloc(
-	sizeof(THING) * COUNT_CONST
+	array_size(COUNT_CONST, sizeof(THING))
  , ...)
)

// 2-factor product, only identifiers.
@@
identifier SIZE, COUNT;
@@

  vmalloc(
-	SIZE * COUNT
+	array_size(COUNT, SIZE)
  , ...)

// 3-factor product with 1 sizeof(type) or sizeof(expression), with
// redundant parens removed.
@@
expression THING;
identifier STRIDE, COUNT;
type TYPE;
@@

(
  vmalloc(
-	sizeof(TYPE) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  vmalloc(
-	sizeof(TYPE) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  vmalloc(
-	sizeof(TYPE) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  vmalloc(
-	sizeof(TYPE) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  vmalloc(
-	sizeof(THING) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  vmalloc(
-	sizeof(THING) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  vmalloc(
-	sizeof(THING) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  vmalloc(
-	sizeof(THING) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
)

// 3-factor product with 2 sizeof(variable), with redundant parens removed.
@@
expression THING1, THING2;
identifier COUNT;
type TYPE1, TYPE2;
@@

(
  vmalloc(
-	sizeof(TYPE1) * sizeof(TYPE2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  vmalloc(
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  vmalloc(
-	sizeof(THING1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  vmalloc(
-	sizeof(THING1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  vmalloc(
-	sizeof(TYPE1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
|
  vmalloc(
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
)

// 3-factor product, only identifiers, with redundant parens removed.
@@
identifier STRIDE, SIZE, COUNT;
@@

(
  vmalloc(
-	(COUNT) * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  vmalloc(
-	COUNT * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  vmalloc(
-	COUNT * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  vmalloc(
-	(COUNT) * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  vmalloc(
-	COUNT * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  vmalloc(
-	(COUNT) * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  vmalloc(
-	(COUNT) * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  vmalloc(
-	COUNT * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
)

// Any remaining multi-factor products, first at least 3-factor products
// when they're not all constants...
@@
expression E1, E2, E3;
constant C1, C2, C3;
@@

(
  vmalloc(C1 * C2 * C3, ...)
|
  vmalloc(
-	E1 * E2 * E3
+	array3_size(E1, E2, E3)
  , ...)
)

// And then all remaining 2 factors products when they're not all constants.
@@
expression E1, E2;
constant C1, C2;
@@

(
  vmalloc(C1 * C2, ...)
|
  vmalloc(
-	E1 * E2
+	array_size(E1, E2)
  , ...)
)

Signed-off-by: Kees Cook <keescook@chromium.org>
2018-06-12 16:19:22 -07:00
Kees Cook
6da2ec5605 treewide: kmalloc() -> kmalloc_array()
The kmalloc() function has a 2-factor argument form, kmalloc_array(). This
patch replaces cases of:

        kmalloc(a * b, gfp)

with:
        kmalloc_array(a * b, gfp)

as well as handling cases of:

        kmalloc(a * b * c, gfp)

with:

        kmalloc(array3_size(a, b, c), gfp)

as it's slightly less ugly than:

        kmalloc_array(array_size(a, b), c, gfp)

This does, however, attempt to ignore constant size factors like:

        kmalloc(4 * 1024, gfp)

though any constants defined via macros get caught up in the conversion.

Any factors with a sizeof() of "unsigned char", "char", and "u8" were
dropped, since they're redundant.

The tools/ directory was manually excluded, since it has its own
implementation of kmalloc().

The Coccinelle script used for this was:

// Fix redundant parens around sizeof().
@@
type TYPE;
expression THING, E;
@@

(
  kmalloc(
-	(sizeof(TYPE)) * E
+	sizeof(TYPE) * E
  , ...)
|
  kmalloc(
-	(sizeof(THING)) * E
+	sizeof(THING) * E
  , ...)
)

// Drop single-byte sizes and redundant parens.
@@
expression COUNT;
typedef u8;
typedef __u8;
@@

(
  kmalloc(
-	sizeof(u8) * (COUNT)
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(__u8) * (COUNT)
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(char) * (COUNT)
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(unsigned char) * (COUNT)
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(u8) * COUNT
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(__u8) * COUNT
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(char) * COUNT
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(unsigned char) * COUNT
+	COUNT
  , ...)
)

// 2-factor product with sizeof(type/expression) and identifier or constant.
@@
type TYPE;
expression THING;
identifier COUNT_ID;
constant COUNT_CONST;
@@

(
- kmalloc
+ kmalloc_array
  (
-	sizeof(TYPE) * (COUNT_ID)
+	COUNT_ID, sizeof(TYPE)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(TYPE) * COUNT_ID
+	COUNT_ID, sizeof(TYPE)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(TYPE) * (COUNT_CONST)
+	COUNT_CONST, sizeof(TYPE)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(TYPE) * COUNT_CONST
+	COUNT_CONST, sizeof(TYPE)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(THING) * (COUNT_ID)
+	COUNT_ID, sizeof(THING)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(THING) * COUNT_ID
+	COUNT_ID, sizeof(THING)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(THING) * (COUNT_CONST)
+	COUNT_CONST, sizeof(THING)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(THING) * COUNT_CONST
+	COUNT_CONST, sizeof(THING)
  , ...)
)

// 2-factor product, only identifiers.
@@
identifier SIZE, COUNT;
@@

- kmalloc
+ kmalloc_array
  (
-	SIZE * COUNT
+	COUNT, SIZE
  , ...)

// 3-factor product with 1 sizeof(type) or sizeof(expression), with
// redundant parens removed.
@@
expression THING;
identifier STRIDE, COUNT;
type TYPE;
@@

(
  kmalloc(
-	sizeof(TYPE) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kmalloc(
-	sizeof(TYPE) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kmalloc(
-	sizeof(TYPE) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kmalloc(
-	sizeof(TYPE) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kmalloc(
-	sizeof(THING) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kmalloc(
-	sizeof(THING) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kmalloc(
-	sizeof(THING) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kmalloc(
-	sizeof(THING) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
)

// 3-factor product with 2 sizeof(variable), with redundant parens removed.
@@
expression THING1, THING2;
identifier COUNT;
type TYPE1, TYPE2;
@@

(
  kmalloc(
-	sizeof(TYPE1) * sizeof(TYPE2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  kmalloc(
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  kmalloc(
-	sizeof(THING1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  kmalloc(
-	sizeof(THING1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  kmalloc(
-	sizeof(TYPE1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
|
  kmalloc(
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
)

// 3-factor product, only identifiers, with redundant parens removed.
@@
identifier STRIDE, SIZE, COUNT;
@@

(
  kmalloc(
-	(COUNT) * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	COUNT * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	COUNT * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	(COUNT) * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	COUNT * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	(COUNT) * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	(COUNT) * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	COUNT * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
)

// Any remaining multi-factor products, first at least 3-factor products,
// when they're not all constants...
@@
expression E1, E2, E3;
constant C1, C2, C3;
@@

(
  kmalloc(C1 * C2 * C3, ...)
|
  kmalloc(
-	(E1) * E2 * E3
+	array3_size(E1, E2, E3)
  , ...)
|
  kmalloc(
-	(E1) * (E2) * E3
+	array3_size(E1, E2, E3)
  , ...)
|
  kmalloc(
-	(E1) * (E2) * (E3)
+	array3_size(E1, E2, E3)
  , ...)
|
  kmalloc(
-	E1 * E2 * E3
+	array3_size(E1, E2, E3)
  , ...)
)

// And then all remaining 2 factors products when they're not all constants,
// keeping sizeof() as the second factor argument.
@@
expression THING, E1, E2;
type TYPE;
constant C1, C2, C3;
@@

(
  kmalloc(sizeof(THING) * C2, ...)
|
  kmalloc(sizeof(TYPE) * C2, ...)
|
  kmalloc(C1 * C2 * C3, ...)
|
  kmalloc(C1 * C2, ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(TYPE) * (E2)
+	E2, sizeof(TYPE)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(TYPE) * E2
+	E2, sizeof(TYPE)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(THING) * (E2)
+	E2, sizeof(THING)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(THING) * E2
+	E2, sizeof(THING)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	(E1) * E2
+	E1, E2
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	(E1) * (E2)
+	E1, E2
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	E1 * E2
+	E1, E2
  , ...)
)

Signed-off-by: Kees Cook <keescook@chromium.org>
2018-06-12 16:19:22 -07:00
Linus Torvalds
2857676045 - Introduce arithmetic overflow test helper functions (Rasmus)
- Use overflow helpers in 2-factor allocators (Kees, Rasmus)
 - Introduce overflow test module (Rasmus, Kees)
 - Introduce saturating size helper functions (Matthew, Kees)
 - Treewide use of struct_size() for allocators (Kees)
 -----BEGIN PGP SIGNATURE-----
 Comment: Kees Cook <kees@outflux.net>
 
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Merge tag 'overflow-v4.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux

Pull overflow updates from Kees Cook:
 "This adds the new overflow checking helpers and adds them to the
  2-factor argument allocators. And this adds the saturating size
  helpers and does a treewide replacement for the struct_size() usage.
  Additionally this adds the overflow testing modules to make sure
  everything works.

  I'm still working on the treewide replacements for allocators with
  "simple" multiplied arguments:

     *alloc(a * b, ...) -> *alloc_array(a, b, ...)

  and

     *zalloc(a * b, ...) -> *calloc(a, b, ...)

  as well as the more complex cases, but that's separable from this
  portion of the series. I expect to have the rest sent before -rc1
  closes; there are a lot of messy cases to clean up.

  Summary:

   - Introduce arithmetic overflow test helper functions (Rasmus)

   - Use overflow helpers in 2-factor allocators (Kees, Rasmus)

   - Introduce overflow test module (Rasmus, Kees)

   - Introduce saturating size helper functions (Matthew, Kees)

   - Treewide use of struct_size() for allocators (Kees)"

* tag 'overflow-v4.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
  treewide: Use struct_size() for devm_kmalloc() and friends
  treewide: Use struct_size() for vmalloc()-family
  treewide: Use struct_size() for kmalloc()-family
  device: Use overflow helpers for devm_kmalloc()
  mm: Use overflow helpers in kvmalloc()
  mm: Use overflow helpers in kmalloc_array*()
  test_overflow: Add memory allocation overflow tests
  overflow.h: Add allocation size calculation helpers
  test_overflow: Report test failures
  test_overflow: macrofy some more, do more tests for free
  lib: add runtime test of check_*_overflow functions
  compiler.h: enable builtin overflow checkers and add fallback code
2018-06-06 17:27:14 -07:00
Kees Cook
acafe7e302 treewide: Use struct_size() for kmalloc()-family
One of the more common cases of allocation size calculations is finding
the size of a structure that has a zero-sized array at the end, along
with memory for some number of elements for that array. For example:

struct foo {
    int stuff;
    void *entry[];
};

instance = kmalloc(sizeof(struct foo) + sizeof(void *) * count, GFP_KERNEL);

Instead of leaving these open-coded and prone to type mistakes, we can
now use the new struct_size() helper:

instance = kmalloc(struct_size(instance, entry, count), GFP_KERNEL);

This patch makes the changes for kmalloc()-family (and kvmalloc()-family)
uses. It was done via automatic conversion with manual review for the
"CHECKME" non-standard cases noted below, using the following Coccinelle
script:

// pkey_cache = kmalloc(sizeof *pkey_cache + tprops->pkey_tbl_len *
//                      sizeof *pkey_cache->table, GFP_KERNEL);
@@
identifier alloc =~ "kmalloc|kzalloc|kvmalloc|kvzalloc";
expression GFP;
identifier VAR, ELEMENT;
expression COUNT;
@@

- alloc(sizeof(*VAR) + COUNT * sizeof(*VAR->ELEMENT), GFP)
+ alloc(struct_size(VAR, ELEMENT, COUNT), GFP)

// mr = kzalloc(sizeof(*mr) + m * sizeof(mr->map[0]), GFP_KERNEL);
@@
identifier alloc =~ "kmalloc|kzalloc|kvmalloc|kvzalloc";
expression GFP;
identifier VAR, ELEMENT;
expression COUNT;
@@

- alloc(sizeof(*VAR) + COUNT * sizeof(VAR->ELEMENT[0]), GFP)
+ alloc(struct_size(VAR, ELEMENT, COUNT), GFP)

// Same pattern, but can't trivially locate the trailing element name,
// or variable name.
@@
identifier alloc =~ "kmalloc|kzalloc|kvmalloc|kvzalloc";
expression GFP;
expression SOMETHING, COUNT, ELEMENT;
@@

- alloc(sizeof(SOMETHING) + COUNT * sizeof(ELEMENT), GFP)
+ alloc(CHECKME_struct_size(&SOMETHING, ELEMENT, COUNT), GFP)

Signed-off-by: Kees Cook <keescook@chromium.org>
2018-06-06 11:15:43 -07:00
Joe Perches
6a73cf46ce 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>
2018-05-28 11:27:20 +02:00
Colin Ian King
6231a895f5 ALSA: seq: fix spelling mistake "Unamed" -> "Unnamed"
Trivial fix to spelling mistake in string

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-05-26 23:59:32 +02:00
Takashi Iwai
ed14d9ae53 Merge branch 'topic/timer-fixes' into for-next
Pull the fixes for possible races in the resolution callback.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-05-18 08:55:36 +02:00
Takashi Iwai
9d4d207d13 ALSA: timer: Assure timer resolution access always locked
There are still many places calling the timer's hw.c_resolution
callback without lock, and this may lead to some races, as we faced in
the commit a820ccbe21 ("ALSA: pcm: Fix UAF at PCM release via PCM
timer access").

This patch changes snd_timer_resolution() to take the timer->lock for
avoiding the races.  A place calling this function already inside the
lock (from the notifier) is replaced with the
snd_timer_hw_resolution() accordingly, as well as wrapping with the
lock around another place calling snd_timer_hw_resolution(), too.

Reported-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-05-18 08:49:13 +02:00
Takashi Iwai
21244e3d6a ALSA: seq: Avoid open-code for getting timer resolution
Instead of open-coding for getting the timer resolution, use the
standard snd_timer_resolution() helper.

The original code falls back to the callback function when the
resolution is zero, but it must be always so when the callback
function is defined.  So this should be no functional change.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-05-18 08:49:13 +02:00
Takashi Iwai
fdcb5761c1 ALSA: timer: Simplify timer hw resolution calls
There multiple open-codes to get the hardware timer resolution.
Make a local helper function snd_timer_hw_resolution() and call it
from all relevant places.

There is no functional change by this, just a preliminary work for the
following timer resolution hardening patch.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-05-18 08:49:12 +02:00
Ben Hutchings
3ae1809725 ALSA: timer: Fix pause event notification
Commit f65e0d2998 ("ALSA: timer: Call notifier in the same spinlock")
combined the start/continue and stop/pause functions, and in doing so
changed the event code for the pause case to SNDRV_TIMER_EVENT_CONTINUE.
Change it back to SNDRV_TIMER_EVENT_PAUSE.

Fixes: f65e0d2998 ("ALSA: timer: Call notifier in the same spinlock")
Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Cc: stable@vger.kernel.org
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-05-18 08:43:59 +02:00
Takashi Iwai
dc82e52492 ALSA: core: Assure control device to be registered at last
The commit 289ca025ee ("ALSA: Use priority list for managing device
list") changed the way to register/disconnect/free devices via a
single priority list.  This helped to make behavior consistent, but it
also changed a slight behavior change: namely, the control device is
registered earlier than others, while it was supposed to be the very
last one.

I've put SNDRV_DEV_CONTROL in the current position as the release of
ctl elements often conflict with the private ctl elements some PCM or
other components may create, which often leads to a double-free.
But, the order of register and disconnect should be indeed fixed as
expected in the early days: the control device gets registered at
last, and disconnected at first.

This patch changes the priority list order to move SNDRV_DEV_CONTROL
as the last guy to assure the register / disconnect order.  Meanwhile,
for keeping the messy resource release order, manually treat the
control and lowlevel devices as last freed one.

Additional note:
The lowlevel device is the device where a card driver creates at
probe.  And, we still keep the release order control -> lowlevel, as
there might  be link from a control element back to a lowlevel object.

Fixes: 289ca025ee ("ALSA: Use priority list for managing device list")
Reported-by: Tzung-Bi Shih <tzungbi@google.com>
Tested-by: Tzung-Bi Shih <tzungbi@google.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-05-17 08:21:23 +02:00
Takashi Iwai
8def12d9cd Merge branch 'for-linus' into for-next
Back-merge of UAC3 fixes for applying further enhancements.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-05-15 07:30:23 +02:00
Takashi Sakamoto
841bdb7c0b ALSA: vmaster: use position offset macro of TLV data
A series of SNDRV_CTL_TLVO_XXX macro was introduced for position offset
of TLV data. This commit applies a code optimization.

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-05-14 17:47:48 +02:00
Wenwen Wang
3f12888dfa ALSA: control: fix a redundant-copy issue
In snd_ctl_elem_add_compat(), the fields of the struct 'data' need to be
copied from the corresponding fields of the struct 'data32' in userspace.
This is achieved by invoking copy_from_user() and get_user() functions. The
problem here is that the 'type' field is copied twice. One is by
copy_from_user() and one is by get_user(). Given that the 'type' field is
not used between the two copies, the second copy is *completely* redundant
and should be removed for better performance and cleanup. Also, these two
copies can cause inconsistent data: as the struct 'data32' resides in
userspace and a malicious userspace process can race to change the 'type'
field between the two copies to cause inconsistent data. Depending on how
the data is used in the future, such an inconsistency may cause potential
security risks.

For above reasons, we should take out the second copy.

Signed-off-by: Wenwen Wang <wang6495@umn.edu>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-05-13 09:27:57 +02:00
Anna-Maria Gleixner
10aa7cad37 ALSA: pcm: Hide local_irq_disable/enable() and local_irqsave/restore()
The snd_pcm_stream_lock_irq*() functions decouple disabling interrupts
from the actual locking process. This does not work as expected if the
locking primitives are replaced like on preempt-rt.

Provide one function for locking which uses correct locking primitives.

Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-05-04 18:57:13 +02:00
Takashi Iwai
f13876e2c3 ALSA: pcm: Check PCM state at xfern compat ioctl
Since snd_pcm_ioctl_xfern_compat() has no PCM state check, it may go
further and hit the sanity check pcm_sanity_check() when the ioctl is
called right after open.  It may eventually spew a kernel warning, as
triggered by syzbot, depending on kconfig.

The lack of PCM state check there was just an oversight.  Although
it's no real crash, the spurious kernel warning is annoying, so let's
add the proper check.

Reported-by: syzbot+1dac3a4f6bc9c1c675d4@syzkaller.appspotmail.com
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-05-02 08:54:54 +02:00
Takashi Iwai
8f22e52528 ALSA: seq: Fix races at MIDI encoding in snd_virmidi_output_trigger()
The sequencer virmidi code has an open race at its output trigger
callback: namely, virmidi keeps only one event packet for processing
while it doesn't protect for concurrent output trigger calls.

snd_virmidi_output_trigger() tries to process the previously
unfinished event before starting encoding the given MIDI stream, but
this is done without any lock.  Meanwhile, if another rawmidi stream
starts the output trigger, this proceeds further, and overwrites the
event package that is being processed in another thread.  This
eventually corrupts and may lead to the invalid memory access if the
event type is like SYSEX.

The fix is just to move the spinlock to cover both the pending event
and the new stream.

The bug was spotted by a new fuzzer, RaceFuzzer.

BugLink: http://lkml.kernel.org/r/20180426045223.GA15307@dragonet.kaist.ac.kr
Reported-by: DaeRyong Jeong <threeearcat@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-04-27 17:50:37 +02:00
Takashi Iwai
4d31c6e41e Merge branch 'for-linus' into for-next
Back-merge 4.17-rc3 fixes for further development.
This will bump the base to 4.17-rc2, too.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-04-25 16:44:36 +02:00
Takashi Iwai
8d218dd811 ALSA: seq: oss: Hardening for potential Spectre v1
As Smatch recently suggested, a few places in OSS sequencer codes may
expand the array directly from the user-space value with speculation,
namely there are a significant amount of references to either
info->ch[] or dp->synths[] array:

  sound/core/seq/oss/seq_oss_event.c:315 note_on_event() warn: potential spectre issue 'info->ch' (local cap)
  sound/core/seq/oss/seq_oss_event.c:362 note_off_event() warn: potential spectre issue 'info->ch' (local cap)
  sound/core/seq/oss/seq_oss_synth.c:470 snd_seq_oss_synth_load_patch() warn: potential spectre issue 'dp->synths' (local cap)
  sound/core/seq/oss/seq_oss_event.c:293 note_on_event() warn: potential spectre issue 'dp->synths'
  sound/core/seq/oss/seq_oss_event.c:353 note_off_event() warn: potential spectre issue 'dp->synths'
  sound/core/seq/oss/seq_oss_synth.c:506 snd_seq_oss_synth_sysex() warn: potential spectre issue 'dp->synths'
  sound/core/seq/oss/seq_oss_synth.c:580 snd_seq_oss_synth_ioctl() warn: potential spectre issue 'dp->synths'

Although all these seem doing only the first load without further
reference, we may want to stay in a safer side, so hardening with
array_index_nospec() would still make sense.

We may put array_index_nospec() at each place, but here we take a
different approach:

- For dp->synths[], change the helpers to retrieve seq_oss_synthinfo
  pointer directly instead of the array expansion at each place

- For info->ch[], harden in a normal way, as there are only a couple
  of places

As a result, the existing helper, snd_seq_oss_synth_is_valid() is
replaced with snd_seq_oss_synth_info().  Also, we cover MIDI device
where a similar array expansion is done, too, although it wasn't
reported by Smatch.

BugLink: https://marc.info/?l=linux-kernel&m=152411496503418&w=2
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-04-25 10:37:45 +02:00
Takashi Iwai
f5e94b4c6e ALSA: seq: oss: Fix unbalanced use lock for synth MIDI device
When get_synthdev() is called for a MIDI device, it returns the fixed
midi_synth_dev without the use refcounting.  OTOH, the caller is
supposed to unreference unconditionally after the usage, so this would
lead to unbalanced refcount.

This patch corrects the behavior and keep up the refcount balance also
for the MIDI synth device.

Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-04-25 10:37:45 +02:00
Souptick Joarder
41412fe921 ALSA: pcm: Change return type to vm_fault_t
Use new return type vm_fault_t for fault handler. For
now, this is just documenting that the function returns
a VM_FAULT value rather than an errno. Once all instances
are converted, vm_fault_t will become a distinct type.

Commit 1c8f422059 ("mm: change return type to vm_fault_t")

Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com>
Reviewed-by: Matthew Wilcox <mawilcox@microsoft.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-04-25 08:15:45 +02:00
Takashi Iwai
1ba7862f1f ALSA: control: Fix missing __user annotation
There is one place missing __user annotation to the pointer used by
the recent code refactoring.  Reported by sparse.

Fixes: 450296f305 ("ALSA: control: code refactoring TLV ioctl handler")
Reviewed-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-04-23 16:19:52 +02:00
David Henningsson
f853dcaae2 ALSA: core: Report audio_tstamp in snd_pcm_sync_ptr
It looks like a simple mistake that this struct member
was forgotten.

Audio_tstamp isn't used much, and on some archs (such as x86) this
ioctl is not used by default, so that might be the reason why this
has slipped for so long.

Fixes: 4eeaaeaea1 ("ALSA: core: add hooks for audio timestamps")
Signed-off-by: David Henningsson <diwic@ubuntu.com>
Reviewed-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Cc: <stable@vger.kernel.org> # v3.8+
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-04-23 08:47:03 +02:00
Jeffery Miller
912e4c3320 ALSA: pcm: Return negative delays from SNDRV_PCM_IOCTL_DELAY.
The commit c2c86a9717 ("ALSA: pcm: Remove set_fs() in PCM core code")
changed SNDRV_PCM_IOCTL_DELAY to return an inconsistent error instead of a
negative delay.  Originally the call would succeed and return the negative
delay.  The Chromium OS Audio Server (CRAS) gets confused and hangs when
the error is returned instead of the negative delay.

Help CRAS avoid the issue by rolling back the behavior to return a
negative delay instead of an error.

Fixes: c2c86a9717 ("ALSA: pcm: Remove set_fs() in PCM core code")
Signed-off-by: Jeffery Miller <jmiller@neverware.com>
Cc: <stable@vger.kernel.org> # v4.13+
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-04-23 08:41:35 +02:00
Takashi Iwai
8a56ef4f3f ALSA: rawmidi: Fix missing input substream checks in compat ioctls
Some rawmidi compat ioctls lack of the input substream checks
(although they do check only for rfile->output).  This many eventually
lead to an Oops as NULL substream is passed to the rawmidi core
functions.

Fix it by adding the proper checks before each function call.

The bug was spotted by syzkaller.

Reported-by: syzbot+f7a0348affc3b67bc617@syzkaller.appspotmail.com
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-04-19 18:16:15 +02:00
Takashi Iwai
c99c5a3bb5 ALSA: pcm: Unify delay calculation in snd_pcm_status() and snd_pcm_delay()
Yet another slight code cleanup: there are two places where
calculating the PCM delay, and they can be unified in a single
helper.  It reduces the multiple open codes.

Reviewed-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-04-17 13:01:16 +02:00
Takashi Iwai
6448fcba2a ALSA: pcm: Unify playback and capture poll callbacks
The poll callbacks for playback and capture directions are doing
fairly similar but with a slight difference.  This patch unifies the
two functions into a single callback.  The advantage of this
refactoring is that the direction-specific procedures become clearer.

There should be no functional change but only the code cleanup.

Reviewed-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-04-17 07:37:24 +02:00
Takashi Iwai
763e5067aa ALSA: pcm: Clean up with snd_pcm_avail() and snd_pcm_hw_avail() helpers
Introduce two new direction-neutral helpers to calculate the avail and
hw_avail values, and clean up the code with them.

The two separated forward and rewind functions are gathered to the
unified functions.

No functional change but only code reductions.

Reviewed-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-04-17 07:37:13 +02:00
Takashi Iwai
e1a3a981e3 ALSA: pcm: Remove WARN_ON() at snd_pcm_hw_params() error
snd_pcm_hw_params() (more exactly snd_pcm_hw_params_choose()) contains
a check of the return error from snd_pcm_hw_param_first() and _last()
with snd_BUG_ON() -- i.e. it may trigger WARN_ON() depending on the
kconfig.

This was a valid check in the past, as these functions shouldn't
return any error if the parameters have been already refined via
snd_pcm_hw_refine() beforehand.  However, the recent rewrite
introduced a kmalloc() in snd_pcm_hw_refine() for removing VLA, and
this brought a possibility to trigger an error.  As a result, syzbot
caught lots of superfluous kernel WARN_ON() and paniced via fault
injection.

As the WARN_ON() is no longer valid with the introduction of
kmalloc(), let's drop snd_BUG_ON() check, in order to make the world
peaceful place again.

Reported-by: syzbot+803e0047ac3a3096bb4f@syzkaller.appspotmail.com
Fixes: 5730f9f744 ("ALSA: pcm: Remove VLA usage")
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-04-09 17:39:31 +02:00
Takashi Iwai
e15dc99dbb ALSA: pcm: Fix endless loop for XRUN recovery in OSS emulation
The commit 02a5d6925c ("ALSA: pcm: Avoid potential races between OSS
ioctls and read/write") split the PCM preparation code to a locked
version, and it added a sanity check of runtime->oss.prepare flag
along with the change.  This leaded to an endless loop when the stream
gets XRUN: namely, snd_pcm_oss_write3() and co call
snd_pcm_oss_prepare() without setting runtime->oss.prepare flag and
the loop continues until the PCM state reaches to another one.

As the function is supposed to execute the preparation
unconditionally, drop the invalid state check there.

The bug was triggered by syzkaller.

Fixes: 02a5d6925c ("ALSA: pcm: Avoid potential races between OSS ioctls and read/write")
Reported-by: syzbot+150189c103427d31a053@syzkaller.appspotmail.com
Reported-by: syzbot+7e3f31a52646f939c052@syzkaller.appspotmail.com
Reported-by: syzbot+4f2016cf5185da7759dc@syzkaller.appspotmail.com
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-04-07 13:10:11 +02:00
Takashi Iwai
a820ccbe21 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>
2018-04-03 08:36:40 +02:00
Takashi Iwai
bc334cb61b Merge branch 'for-next' into for-linus
Preparation for 4.17 merge.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-04-02 19:50:59 +02:00
Takashi Iwai
f6d297df4d ALSA: pcm: Fix mutex unbalance in OSS emulation ioctls
The previous fix 40cab6e88c ("ALSA: pcm: Return -EBUSY for OSS
ioctls changing busy streams") introduced some mutex unbalance; the
check of runtime->oss.rw_ref was inserted in a wrong place after the
mutex lock.

This patch fixes the inconsistency by rewriting with the helper
functions to lock/unlock parameters with the stream check.

Fixes: 40cab6e88c ("ALSA: pcm: Return -EBUSY for OSS ioctls changing busy streams")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-03-27 16:20:02 +02:00
Dan Carpenter
5607dddbfc ALSA: pcm: potential uninitialized return values
Smatch complains that "tmp" can be uninitialized if we do a zero size
write.

Fixes: 02a5d6925c ("ALSA: pcm: Avoid potential races between OSS ioctls and read/write")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-03-27 15:20:19 +02:00
Stefan Roese
9066ae7ff5 ALSA: pcm: Use dma_bytes as size parameter in dma_mmap_coherent()
When trying to use the driver (e.g. aplay *.wav), the 4MiB DMA buffer
will get mmapp'ed in 16KiB chunks. But this fails with the 2nd 16KiB
area, as the page offset is outside of the VMA range (size), which is
currently used as size parameter in snd_pcm_lib_default_mmap(). By
using the DMA buffer size (dma_bytes) instead, the complete DMA buffer
can be mmapp'ed and the issue is fixed.

This issue was detected on an ARM platform (TI AM57xx) using the RME
HDSP MADI PCIe soundcard.

Fixes: 657b1989da ("ALSA: pcm - Use dma_mmap_coherent() if available")
Signed-off-by: Stefan Roese <sr@denx.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-03-26 16:33:50 +02:00
Takashi Iwai
40cab6e88c ALSA: pcm: Return -EBUSY for OSS ioctls changing busy streams
OSS PCM stream management isn't modal but it allows ioctls issued at
any time for changing the parameters.  In the previous hardening
patch ("ALSA: pcm: Avoid potential races between OSS ioctls and
read/write"), we covered these races and prevent the corruption by
protecting the concurrent accesses via params_lock mutex.  However,
this means that some ioctls that try to change the stream parameter
(e.g. channels or format) would be blocked until the read/write
finishes, and it may take really long.

Basically changing the parameter while reading/writing is an invalid
operation, hence it's even more user-friendly from the API POV if it
returns -EBUSY in such a situation.

This patch adds such checks in the relevant ioctls with the addition
of read/write access refcount.

Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-03-23 22:18:05 +01:00
Takashi Iwai
02a5d6925c ALSA: pcm: Avoid potential races between OSS ioctls and read/write
Although we apply the params_lock mutex to the whole read and write
operations as well as snd_pcm_oss_change_params(), we may still face
some races.

First off, the params_lock is taken inside the read and write loop.
This is intentional for avoiding the too long locking, but it allows
the in-between parameter change, which might lead to invalid
pointers.  We check the readiness of the stream and set up via
snd_pcm_oss_make_ready() at the beginning of read and write, but it's
called only once, by assuming that it remains ready in the rest.

Second, many ioctls that may change the actual parameters
(i.e. setting runtime->oss.params=1) aren't protected, hence they can
be processed in a half-baked state.

This patch is an attempt to plug these holes.  The stream readiness
check is moved inside the read/write inner loop, so that the stream is
always set up in a proper state before further processing.  Also, each
ioctl that may change the parameter is wrapped with the params_lock
for avoiding the races.

The issues were triggered by syzkaller in a few different scenarios,
particularly the one below appearing as GPF in loopback_pos_update.

Reported-by: syzbot+c4227aec125487ec3efa@syzkaller.appspotmail.com
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-03-23 22:17:56 +01:00
Takashi Iwai
4654eba8cb Merge branch 'for-linus' into for-next
Back-merge of for-linus branch for applying the further UAC3 patches.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-03-19 17:00:01 +01:00
Takashi Iwai
09b9ddfaa1 ALSA: pcm: Use krealloc() for resizing the rules array
Just a minor simplification.  Change from kcalloc() shouldn't matter
as each array element is fully initialized.

Reviewed-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-03-13 15:37:58 +01:00
Takashi Iwai
5730f9f744 ALSA: pcm: Remove VLA usage
A helper function used by snd_pcm_hw_refine() still keeps using VLA
for timestamps of hw constraint rules that are non-fixed size.

Let's replace the VLA with a simple kmalloc() array.

Reference: https://lkml.org/lkml/2018/3/7/621
Reviewed-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-03-13 15:37:56 +01:00
Takashi Iwai
01c0b4265c ALSA: pcm: Fix UAF in snd_pcm_oss_get_formats()
snd_pcm_oss_get_formats() has an obvious use-after-free around
snd_mask_test() calls, as spotted by syzbot.  The passed format_mask
argument is a pointer to the hw_params object that is freed before the
loop.  What a surprise that it has been present since the original
code of decades ago...

Reported-by: syzbot+4090700a4f13fccaf648@syzkaller.appspotmail.com
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-03-11 10:25:10 +01:00
Takashi Iwai
a2ff19f7b7 ALSA: seq: Clear client entry before deleting else at closing
When releasing a client, we need to clear the clienttab[] entry at
first, then call snd_seq_queue_client_leave().  Otherwise, the
in-flight cell in the queue might be picked up by the timer interrupt
via snd_seq_check_queue() before calling snd_seq_queue_client_leave(),
and it's delivered to another queue while the client is clearing
queues.  This may eventually result in an uncleared cell remaining in
a queue, and the later snd_seq_pool_delete() may need to wait for a
long time until the event gets really processed.

By moving the clienttab[] clearance at the beginning of release, any
event delivery of a cell belonging to this client will fail at a later
point, since snd_seq_client_ptr() returns NULL.  Thus the cell that
was picked up by the timer interrupt will be returned immediately
without further delivery, and the long stall of snd_seq_delete_pool()
can be avoided, too.

Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-03-10 17:30:01 +01:00
Takashi Iwai
d0f8330652 ALSA: seq: Fix possible UAF in snd_seq_check_queue()
Although we've covered the races between concurrent write() and
ioctl() in the previous patch series, there is still a possible UAF in
the following scenario:

A: user client closed		B: timer irq
  -> snd_seq_release()		  -> snd_seq_timer_interrupt()
    -> snd_seq_free_client()	    -> snd_seq_check_queue()
				      -> cell = snd_seq_prioq_cell_peek()
      -> snd_seq_prioq_leave()
         .... removing all cells
      -> snd_seq_pool_done()
         .... vfree()
				      -> snd_seq_compare_tick_time(cell)
				         ... Oops

So the problem is that a cell is peeked and accessed without any
protection until it's retrieved from the queue again via
snd_seq_prioq_cell_out().

This patch tries to address it, also cleans up the code by a slight
refactoring.  snd_seq_prioq_cell_out() now receives an extra pointer
argument.  When it's non-NULL, the function checks the event timestamp
with the given pointer.  The caller needs to pass the right reference
either to snd_seq_tick or snd_seq_realtime depending on the event
timestamp type.

A good news is that the above change allows us to remove the
snd_seq_prioq_cell_peek(), too, thus the patch actually reduces the
code size.

Reviewed-by: Nicolai Stange <nstange@suse.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-03-10 17:29:49 +01:00
Takashi Iwai
85d59b57be ALSA: seq: Remove superfluous snd_seq_queue_client_leave_cells() call
With the previous two fixes for the write / ioctl races:
  ALSA: seq: Don't allow resizing pool in use
  ALSA: seq: More protection for concurrent write and ioctl races
the cells aren't any longer in queues at the point calling
snd_seq_pool_done() in snd_seq_ioctl_set_client_pool().  Hence the
function call snd_seq_queue_client_leave_cells() can be dropped safely
from there.

Suggested-by: Nicolai Stange <nstange@suse.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-03-08 12:06:07 +01:00
Takashi Iwai
7bd8009156 ALSA: seq: More protection for concurrent write and ioctl races
This patch is an attempt for further hardening against races between
the concurrent write and ioctls.  The previous fix d15d662e89
("ALSA: seq: Fix racy pool initializations") covered the race of the
pool initialization at writer and the pool resize ioctl by the
client->ioctl_mutex (CVE-2018-1000004).  However, basically this mutex
should be applied more widely to the whole write operation for
avoiding the unexpected pool operations by another thread.

The only change outside snd_seq_write() is the additional mutex
argument to helper functions, so that we can unlock / relock the given
mutex temporarily during schedule() call for blocking write.

Fixes: d15d662e89 ("ALSA: seq: Fix racy pool initializations")
Reported-by: 范龙飞 <long7573@126.com>
Reported-by: Nicolai Stange <nstange@suse.de>
Reviewed-and-tested-by: Nicolai Stange <nstange@suse.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-03-08 12:05:37 +01:00
Takashi Iwai
d85739367c ALSA: seq: Don't allow resizing pool in use
This is a fix for a (sort of) fallout in the recent commit
d15d662e89 ("ALSA: seq: Fix racy pool initializations") for
CVE-2018-1000004.
As the pool resize deletes the existing cells, it may lead to a race
when another thread is writing concurrently, eventually resulting a
UAF.

A simple workaround is not to allow the pool resizing when the pool is
in use.  It's an invalid behavior in anyway.

Fixes: d15d662e89 ("ALSA: seq: Fix racy pool initializations")
Reported-by: 范龙飞 <long7573@126.com>
Reported-by: Nicolai Stange <nstange@suse.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-03-08 08:59:26 +01:00
Takashi Iwai
7a33a02ffb ALSA: vmaster: Zero-clear ctl before calling slave get
Use kzalloc() instead of kmalloc() so that we don't need to rely fully
on the slave get() callback to clear the control value that might be
copied to user-space.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-03-08 08:41:13 +01:00
Takashi Iwai
2e2c177ca8 ALSA: vmaster: Propagate slave error
In slave_update() of vmaster code ignores the error from the slave
get() callback and copies the values.  It's not only about the missing
error code but also that this may potentially lead to a leak of
uninitialized variables when the slave get() don't clear them.

This patch fixes slave_update() not to copy the potentially
uninitialized values when an error is returned from the slave get()
callback, and to propagate the error value properly.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-03-08 08:41:12 +01:00
Richard Fitzgerald
dd5f313be0 ALSA: control: Fix a bunch of whitespace errors
Remove a bunch of trailing whitespace errors. They are
fairly annoying if you have your editor set to strip trailing
whitespace because you find you've introduced more changes
than you were trying to make.

Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-02-28 08:18:26 +01:00
Takashi Iwai
3b8bd500c9 Merge branch 'for-linus' into for-next
Back-merge for applying a cleanup to core/control

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-02-28 08:17:54 +01:00
Richard Fitzgerald
5a23699a39 ALSA: control: Fix memory corruption risk in snd_ctl_elem_read
The patch "ALSA: control: code refactoring for ELEM_READ/ELEM_WRITE
operations" introduced a potential for kernel memory corruption due
to an incorrect if statement allowing non-readable controls to fall
through and call the get function. For TLV controls a driver can omit
SNDRV_CTL_ELEM_ACCESS_READ to ensure that only the TLV get function
can be called. Instead the normal get() can be invoked unexpectedly
and as the driver expects that this will only be called for controls
<= 512 bytes, potentially try to copy >512 bytes into the 512 byte
return array, so corrupting kernel memory.

The problem is an attempt to refactor the snd_ctl_elem_read function
to invert the logic so that it conditionally aborted if the control
is unreadable instead of conditionally executing. But the if statement
wasn't inverted correctly.

The correct inversion of

    if (a && !b)

is
    if (!a || b)

Fixes: becf9e5d55 ("ALSA: control: code refactoring for ELEM_READ/ELEM_WRITE operations")
Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-02-28 08:15:56 +01:00
Jaejoong Kim
ef21e17501 ALSA: Use scnprintf() instead of snprintf() for show
The show() method should use scnprintf() not snprintf() because snprintf()
may returns a value that exceeds its second argument.

Signed-off-by: Jaejoong Kim <climbbb.kim@gmail.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-02-27 09:16:52 +01:00
Takashi Iwai
d15d662e89 ALSA: seq: Fix racy pool initializations
ALSA sequencer core initializes the event pool on demand by invoking
snd_seq_pool_init() when the first write happens and the pool is
empty.  Meanwhile user can reset the pool size manually via ioctl
concurrently, and this may lead to UAF or out-of-bound accesses since
the function tries to vmalloc / vfree the buffer.

A simple fix is to just wrap the snd_seq_pool_init() call with the
recently introduced client->ioctl_mutex; as the calls for
snd_seq_pool_init() from other side are always protected with this
mutex, we can avoid the race.

Reported-by: 范龙飞 <long7573@126.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-02-14 10:39:08 +01:00
Linus Torvalds
a9a08845e9 vfs: do bulk POLL* -> EPOLL* replacement
This is the mindless scripted replacement of kernel use of POLL*
variables as described by Al, done by this script:

    for V in IN OUT PRI ERR RDNORM RDBAND WRNORM WRBAND HUP RDHUP NVAL MSG; do
        L=`git grep -l -w POLL$V | grep -v '^t' | grep -v /um/ | grep -v '^sa' | grep -v '/poll.h$'|grep -v '^D'`
        for f in $L; do sed -i "-es/^\([^\"]*\)\(\<POLL$V\>\)/\\1E\\2/" $f; done
    done

with de-mangling cleanups yet to come.

NOTE! On almost all architectures, the EPOLL* constants have the same
values as the POLL* constants do.  But they keyword here is "almost".
For various bad reasons they aren't the same, and epoll() doesn't
actually work quite correctly in some cases due to this on Sparc et al.

The next patch from Al will sort out the final differences, and we
should be all done.

Scripted-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-02-11 14:34:03 -08:00
Linus Torvalds
19e7b5f994 Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull misc vfs updates from Al Viro:
 "All kinds of misc stuff, without any unifying topic, from various
  people.

  Neil's d_anon patch, several bugfixes, introduction of kvmalloc
  analogue of kmemdup_user(), extending bitfield.h to deal with
  fixed-endians, assorted cleanups all over the place..."

* 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (28 commits)
  alpha: osf_sys.c: use timespec64 where appropriate
  alpha: osf_sys.c: fix put_tv32 regression
  jffs2: Fix use-after-free bug in jffs2_iget()'s error handling path
  dcache: delete unused d_hash_mask
  dcache: subtract d_hash_shift from 32 in advance
  fs/buffer.c: fold init_buffer() into init_page_buffers()
  fs: fold __inode_permission() into inode_permission()
  fs: add RWF_APPEND
  sctp: use vmemdup_user() rather than badly open-coding memdup_user()
  snd_ctl_elem_init_enum_names(): switch to vmemdup_user()
  replace_user_tlv(): switch to vmemdup_user()
  new primitive: vmemdup_user()
  memdup_user(): switch to GFP_USER
  eventfd: fold eventfd_ctx_get() into eventfd_ctx_fileget()
  eventfd: fold eventfd_ctx_read() into eventfd_read()
  eventfd: convert to use anon_inode_getfd()
  nfs4file: get rid of pointless include of btrfs.h
  uvc_v4l2: clean copyin/copyout up
  vme_user: don't use __copy_..._user()
  usx2y: don't bother with memdup_user() for 16-byte structure
  ...
2018-01-31 09:25:20 -08:00
Linus Torvalds
168fe32a07 Merge branch 'misc.poll' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull poll annotations from Al Viro:
 "This introduces a __bitwise type for POLL### bitmap, and propagates
  the annotations through the tree. Most of that stuff is as simple as
  'make ->poll() instances return __poll_t and do the same to local
  variables used to hold the future return value'.

  Some of the obvious brainos found in process are fixed (e.g. POLLIN
  misspelled as POLL_IN). At that point the amount of sparse warnings is
  low and most of them are for genuine bugs - e.g. ->poll() instance
  deciding to return -EINVAL instead of a bitmap. I hadn't touched those
  in this series - it's large enough as it is.

  Another problem it has caught was eventpoll() ABI mess; select.c and
  eventpoll.c assumed that corresponding POLL### and EPOLL### were
  equal. That's true for some, but not all of them - EPOLL### are
  arch-independent, but POLL### are not.

  The last commit in this series separates userland POLL### values from
  the (now arch-independent) kernel-side ones, converting between them
  in the few places where they are copied to/from userland. AFAICS, this
  is the least disruptive fix preserving poll(2) ABI and making epoll()
  work on all architectures.

  As it is, it's simply broken on sparc - try to give it EPOLLWRNORM and
  it will trigger only on what would've triggered EPOLLWRBAND on other
  architectures. EPOLLWRBAND and EPOLLRDHUP, OTOH, are never triggered
  at all on sparc. With this patch they should work consistently on all
  architectures"

* 'misc.poll' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (37 commits)
  make kernel-side POLL... arch-independent
  eventpoll: no need to mask the result of epi_item_poll() again
  eventpoll: constify struct epoll_event pointers
  debugging printk in sg_poll() uses %x to print POLL... bitmap
  annotate poll(2) guts
  9p: untangle ->poll() mess
  ->si_band gets POLL... bitmap stored into a user-visible long field
  ring_buffer_poll_wait() return value used as return value of ->poll()
  the rest of drivers/*: annotate ->poll() instances
  media: annotate ->poll() instances
  fs: annotate ->poll() instances
  ipc, kernel, mm: annotate ->poll() instances
  net: annotate ->poll() instances
  apparmor: annotate ->poll() instances
  tomoyo: annotate ->poll() instances
  sound: annotate ->poll() instances
  acpi: annotate ->poll() instances
  crypto: annotate ->poll() instances
  block: annotate ->poll() instances
  x86: annotate ->poll() instances
  ...
2018-01-30 17:58:07 -08:00
Al Viro
59aeaf3fef snd_ctl_elem_init_enum_names(): switch to vmemdup_user()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-01-19 22:35:58 -05:00
Al Viro
88a890375f replace_user_tlv(): switch to vmemdup_user()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-01-19 22:35:36 -05:00
Luis de Bethencourt
3c7f69195c ALSA: pcm: Fix trailing semicolon
The trailing semicolon is an empty statement that does no operation.
Removing it since it doesn't do anything.

Signed-off-by: Luis de Bethencourt <luisbg@kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-01-16 14:29:48 +01:00
Takashi Iwai
671ec859e5 ALSA: seq: Process queue tempo/ppq change in a shot
The SNDRV_SEQ_IOCTL_SET_QUEUE_TEMPO ioctl sets the tempo and the ppq
in a single call, while the current implementation updates each value
one by one.  This is a bit racy, and also suboptimal from the
performance POV, as each call does re-acquire the lock and invokes
the update of ALSA timer resolution.

This patch reorganizes the code slightly so that we change both the
tempo and the ppq in a shot.  The skew value can be put into the same
lock, but this is rather a rarely used feature and completely
independent from the temp/ppq (it's evaluated only in the interrupt),
so it's left as it was.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-01-15 16:48:36 +01:00
Takashi Iwai
4ea5553a51 Merge branch 'for-linus' into for-next
Back-merge to the development branch for further fixes of sequencer
stuff.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-01-15 16:45:15 +01:00
Takashi Iwai
b3defb791b ALSA: seq: Make ioctls race-free
The ALSA sequencer ioctls have no protection against racy calls while
the concurrent operations may lead to interfere with each other.  As
reported recently, for example, the concurrent calls of setting client
pool with a combination of write calls may lead to either the
unkillable dead-lock or UAF.

As a slightly big hammer solution, this patch introduces the mutex to
make each ioctl exclusive.  Although this may reduce performance via
parallel ioctl calls, usually it's not demanded for sequencer usages,
hence it should be negligible.

Reported-by: Luo Quan <a4651386@163.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-01-11 14:37:51 +01:00
Takashi Iwai
23b19b7b50 ALSA: pcm: Remove yet superfluous WARN_ON()
muldiv32() contains a snd_BUG_ON() (which is morphed as WARN_ON() with
debug option) for checking the case of 0 / 0.  This would be helpful
if this happens only as a logical error; however, since the hw refine
is performed with any data set provided by user, the inconsistent
values that can trigger such a condition might be passed easily.
Actually, syzbot caught this by passing some zero'ed old hw_params
ioctl.

So, having snd_BUG_ON() there is simply superfluous and rather
harmful to give unnecessary confusions.  Let's get rid of it.

Reported-by: syzbot+7e6ee55011deeebce15d@syzkaller.appspotmail.com
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-01-11 00:01:26 +01:00
Takashi Iwai
c64ed5dd9f ALSA: pcm: Use ERESTARTSYS instead of EINTR in OSS emulation
Fix the last standing EINTR in the whole subsystem.  Use more correct
ERESTARTSYS for pending signals.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-01-09 08:53:44 +01:00
Takashi Iwai
9dd55cb419 Merge branch 'for-linus' into for-next
Back-merge to continue fixing the OSS emulation code.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-01-09 08:49:53 +01:00
Takashi Iwai
900498a34a ALSA: pcm: Allow aborting mutex lock at OSS read/write loops
PCM OSS read/write loops keep taking the mutex lock for the whole
read/write, and this might take very long when the exceptionally high
amount of data is given.  Also, since it invokes with mutex_lock(),
the concurrent read/write becomes unbreakable.

This patch tries to address these issues by replacing mutex_lock()
with mutex_lock_interruptible(), and also splits / re-takes the lock
at each read/write period chunk, so that it can switch the context
more finely if requested.

Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-01-08 16:40:26 +01:00
Takashi Iwai
29159a4ed7 ALSA: pcm: Abort properly at pending signal in OSS read/write loops
The loops for read and write in PCM OSS emulation have no proper check
of pending signals, and they keep processing even after user tries to
break.  This results in a very long delay, often seen as RCU stall
when a huge unprocessed bytes remain queued.  The bug could be easily
triggered by syzkaller.

As a simple workaround, this patch adds the proper check of pending
signals and aborts the loop appropriately.

Reported-by: syzbot+993cb4cfcbbff3947c21@syzkaller.appspotmail.com
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-01-08 15:16:52 +01:00
Takashi Iwai
fb51f1cd06 ALSA: pcm: Workaround for weird PulseAudio behavior on rewind error
The commit 9027c4639e ("ALSA: pcm: Call ack() whenever appl_ptr is
updated") introduced the possible error code returned from the PCM
rewind ioctl.  Basically the change was for handling the indirect PCM
more correctly, but ironically, it caused rather a side-effect:
PulseAudio gets pissed off when receiving an error from rewind, throws
everything away and stops processing further, resulting in the
silence.

It's clearly a failure in the application side, so the best would be
to fix that bug in PA.  OTOH, PA is mostly the only user of the rewind
feature, so it's not good to slap the sole customer.

This patch tries to mitigate the situation: instead of returning an
error, now the rewind ioctl returns zero when the driver can't rewind.
It indicates that no rewind was performed, so the behavior is
consistent, at least.

Fixes: 9027c4639e ("ALSA: pcm: Call ack() whenever appl_ptr is updated")
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-01-05 16:07:50 +01:00