When the parameter changes fails, we don't need to keep the old
temporary buffers. Release those (and plugin instances) upon errors
for reducing dead memory footprint. Since we always call it at the
exit of snd_pcm_oss_changes_params_locked(), the explicit calls of
snd_pcm_oss_plugin_clear() can be dropped, too.
Along with it, unify the buffer-free calls to a single helper and call
it from the needed places.
Link: https://lore.kernel.org/r/20220318082157.29769-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
We've got syzbot reports hitting INT_MAX overflow at vmalloc()
allocation that is called from snd_pcm_plug_alloc(). Although we
apply the restrictions to input parameters, it's based only on the
hw_params of the underlying PCM device. Since the PCM OSS layer
allocates a temporary buffer for the data conversion, the size may
become unexpectedly large when more channels or higher rates is given;
in the reported case, it went over INT_MAX, hence it hits WARN_ON().
This patch is an attempt to avoid such an overflow and an allocation
for too large buffers. First off, it adds the limit of 1MB as the
upper bound for period bytes. This must be large enough for all use
cases, and we really don't want to handle a larger temporary buffer
than this size. The size check is performed at two places, where the
original period bytes is calculated and where the plugin buffer size
is calculated.
In addition, the driver uses array_size() and array3_size() for
multiplications to catch overflows for the converted period size and
buffer bytes.
Reported-by: syzbot+72732c532ac1454eeee9@syzkaller.appspotmail.com
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/00000000000085b1b305da5a66f3@google.com
Link: https://lore.kernel.org/r/20220318082036.29699-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
A couple of calls in snd_pcm_oss_change_params_locked() ignore the
possible errors. Catch those errors and abort the operation for
avoiding further problems.
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20211201073606.11660-4-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Fix compile error when OSS_DEBUG is enabled:
sound/core/oss/pcm_oss.c: In function 'snd_pcm_oss_set_trigger':
sound/core/oss/pcm_oss.c:2055:10: error: 'substream' undeclared (first
use in this function); did you mean 'csubstream'?
pcm_dbg(substream->pcm, "pcm_oss: trigger = 0x%x\n", trigger);
^
Fixes: 61efcee860 ("ALSA: oss: Use standard printk helpers")
Signed-off-by: Bixuan Cui <cuibixuan@linux.alibaba.com>
Link: https://lore.kernel.org/r/1638349134-110369-1-git-send-email-cuibixuan@linux.alibaba.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
There are a few places doing assignments in if condition in ALSA PCM
and OSS emulation layers, which is a bad coding style that may confuse
readers and occasionally lead to bugs.
This patch is merely for coding-style fixes, no functional changes.
Link: https://lore.kernel.org/r/20210608140540.17885-56-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Building with 'make W=1' shows some warnings about empty function-style
macros:
sound/core/pcm_memory.c: In function 'preallocate_pages':
sound/core/pcm_memory.c:236:49: error: suggest braces around empty body in an 'if' statement [-Werror=empty-body]
236 | preallocate_info_init(substream);
sound/core/seq_device.c: In function 'snd_seq_device_dev_register':
sound/core/seq_device.c:163:41: error: suggest braces around empty body in an 'if' statement [-Werror=empty-body]
163 | queue_autoload_drivers();
Change them to empty inline functions, which are more robust here.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/20210322103128.547199-1-arnd@kernel.org
Signed-off-by: Takashi Iwai <tiwai@suse.de>
strlcpy is deprecated. see: Documentation/process/deprecated.rst
Change the calls that do not use the strlcpy return value to the
preferred strscpy.
Done with cocci script:
@@
expression e1, e2, e3;
@@
- strlcpy(
+ strscpy(
e1, e2, e3);
This cocci script leaves the instances where the return value is
used unchanged.
After this patch, sound/ has 3 uses of strlcpy() that need to be
manually inspected for conversion and changed one day.
$ git grep -w strlcpy sound/
sound/usb/card.c: len = strlcpy(card->longname, s, sizeof(card->longname));
sound/usb/mixer.c: return strlcpy(buf, p->name, buflen);
sound/usb/mixer.c: return strlcpy(buf, p->names[index], buflen);
Miscellenea:
o Remove trailing whitespace in conversion of sound/core/hwdep.c
Link: https://lore.kernel.org/lkml/CAHk-=wgfRnXz0W3D37d01q3JFkr_i_uTL=V6A6G1oUZcprmknw@mail.gmail.com/
Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/22b393d1790bb268769d0bab7bacf0866dcb0c14.camel@perches.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Use DIV_ROUND_CLOSEST() instead of open-coding it. This documents intent
and makes it more clear what is going on for the casual reviewer.
Generated using the following the Coccinelle semantic patch.
// <smpl>
@@
expression x, y;
@@
-((x) + ((y) / 2)) / (y)
+DIV_ROUND_CLOSEST(x, y)
// </smpl>
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Link: https://lore.kernel.org/r/20201223172229.781-13-lars@metafoo.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
There are a few places that call round{up|down}_pow_of_two() with the
value zero, and this causes undefined behavior warnings. Avoid
calling those macros if such a nonsense value is passed; it's a minor
optimization as well, as we handle it as either an error or a value to
be skipped, instead.
Reported-by: syzbot+33ef0b6639a8d2d42b4c@syzkaller.appspotmail.com
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20201218161730.26596-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
syzbot spotted a potential out-of-bounds shift in the PCM OSS layer
where it calculates the buffer size with the arbitrary shift value
given via an ioctl.
Add a range check for avoiding the undefined behavior.
As the value can be treated by a signed integer, the max shift should
be 30.
Reported-by: syzbot+df7dc146ebdd6435eea3@syzkaller.appspotmail.com
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20201209084552.17109-2-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
The PCM OSS mulaw plugin has a check of the format of the counter part
whether it's a linear format. The check is with snd_BUG_ON() that
emits WARN_ON() when the debug config is set, and it confuses
syzkaller as if it were a serious issue. Let's drop snd_BUG_ON() for
avoiding that.
While we're at it, correct the error code to a more suitable, EINVAL.
Reported-by: syzbot+23b22dc2e0b81cbfcc95@syzkaller.appspotmail.com
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20200901131802.18157-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
sizeof(flexible-array-member) triggers a warning because flexible array
members have incomplete type[1]. There are some instances of code in
which the sizeof operator is being incorrectly/erroneously applied to
zero-length arrays and the result is zero. Such instances may be hiding
some bugs. So, this work (flexible-array member conversions) will also
help to get completely rid of those sorts of issues.
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Link: https://lore.kernel.org/r/20200507192223.GA16335@embeddedor
Signed-off-by: Takashi Iwai <tiwai@suse.de>
[ This is again a forward-port of the fix applied for 5.6-base code
(commit 4285de0725) to 5.7-base, hence neither Fixes nor
Cc-to-stable tags are included here -- tiwai ]
The checks of the plugin buffer overflow in the previous fix by commit
f2ecf903ef ("ALSA: pcm: oss: Avoid plugin buffer overflow")
are put in the wrong places mistakenly, which leads to the expected
(repeated) sound when the rate plugin is involved. Fix in the right
places.
Also, at those right places, the zero check is needed for the
termination node, so added there as well, and let's get it done,
finally.
Link: https://lore.kernel.org/r/20200424193843.20397-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
[ This is essentially the same fix as commit ae769d3556, but it's
adapted to the latest code for 5.7; hence it contains no Fixes or
other tags for avoid backport confusion -- tiwai ]
The recent fix for the OOB access in PCM OSS plugins (commit
f2ecf903ef: "ALSA: pcm: oss: Avoid plugin buffer overflow") caused a
regression on OSS applications. The patch introduced the size check
in client and slave size calculations to limit to each plugin's buffer
size, but I overlooked that some code paths call those without
allocating the buffer but just for estimation.
This patch fixes the bug by skipping the size check for those code
paths while keeping checking in the actual transfer calls.
Link: https://lore.kernel.org/r/20200403073818.27943-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
The return value checks in snd_pcm_plug_alloc() are covered with
snd_BUG_ON() macro that may trigger a kernel WARNING depending on the
kconfig. But since the error condition can be triggered by a weird
user space parameter passed to OSS layer, we shouldn't give the kernel
stack trace just for that. As it's a normal error condition, let's
remove snd_BUG_ON() macro usage there.
Reported-by: syzbot+2a59ee7a9831b264f45e@syzkaller.appspotmail.com
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20200312155730.7520-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Both snd_pcm_plug_client_size() and snd_pcm_plug_slave_size() do the
almost same calculations of calling src_frames() and dst_frames() in
the chain, but just to the different directions with each other.
This patch simplifies those functions. Now they return -EINVAL for
the invalid direction, but practically seen, there is no functional
changes at all.
Link: https://lore.kernel.org/r/20200309185855.15693-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Each OSS PCM plugins allocate its internal buffer per pre-calculation
of the max buffer size through the chain of plugins (calling
src_frames and dst_frames callbacks). This works for most plugins,
but the rate plugin might behave incorrectly. The calculation in the
rate plugin involves with the fractional position, i.e. it may vary
depending on the input position. Since the buffer size
pre-calculation is always done with the offset zero, it may return a
shorter size than it might be; this may result in the out-of-bound
access as spotted by fuzzer.
This patch addresses those possible buffer overflow accesses by simply
setting the upper limit per the given buffer size for each plugin
before src_frames() and after dst_frames() calls.
Reported-by: syzbot+e1fe9f44fb8ecf4fb5dd@syzkaller.appspotmail.com
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/000000000000b25ea005a02bcf21@google.com
Link: https://lore.kernel.org/r/20200309082148.19855-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
ALSA PCM OSS layer calls the generic __snd_pcm_lib_xfer() helper for
the actual transfer of the audio data. The xfer helper may sleep long
for waiting for the enough space becoming empty for read/write, and
it does unlock/relock for the substream lock. This works fine, so
far, but a slight problem specific to OSS layer is that OSS layer
wraps yet more mutex (runtime->oss.params_lock) over
__snd_pcm_lib_xfer() call; so this mutex is still locked during a
possible long sleep, and it prevents the whole ioctl and other actions
applied to the given stream.
This patch adds the temporarily unlock and relock of the mutex around
__snd_pcm_lib_xfer() call in the OSS layer to be more friendly to the
concurrent accesses. The long mutex protection itself shouldn't be a
real issue for the normal systems, and its influence appears only on
strange things like fuzzers.
Link: https://lore.kernel.org/r/20200214171643.26212-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertenly introduced[3] to the codebase from now on.
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Link: https://lore.kernel.org/r/20200211193910.GA4596@embeddedor
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Simplify the code with the new macros for PCM format type iterations.
This fixes the sparse warnings nicely:
sound/core/pcm_native.c:2302:26: warning: restricted snd_pcm_format_t degrades to integer
sound/core/pcm_native.c:2306:54: warning: incorrect type in argument 1 (different base types)
sound/core/pcm_native.c:2306:54: expected restricted snd_pcm_format_t [usertype] format
sound/core/pcm_native.c:2306:54: got unsigned int [assigned] k
....
No functional changes, just sparse warning fixes.
Link: https://lore.kernel.org/r/20200206163945.6797-6-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
A few last-minute updates, most of them are the regression fixes:
- AMD HD-audio HDMI runtime PM improvements
- Fixes for HD-audio HDMI regressions wrt DP-MST
- A regression fix for the previous aloop enhancement
- A fix for a long-time problem in PCM OSS layer that was spotted by
fuzzer now
- A few HD-audio quirks
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Merge tag 'sound-fix-5.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound
Pull more sound updates from Takashi Iwai:
"A few last-minute updates, most of them are the regression fixes:
- AMD HD-audio HDMI runtime PM improvements
- Fixes for HD-audio HDMI regressions wrt DP-MST
- A regression fix for the previous aloop enhancement
- A fix for a long-time problem in PCM OSS layer that was spotted by
fuzzer now
- A few HD-audio quirks"
* tag 'sound-fix-5.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound:
ALSA: pcm: oss: Avoid potential buffer overflows
ALSA: hda: hdmi - Keep old slot assignment behavior for Intel platforms
ALSA: hda: Modify stream stripe mask only when needed
ALSA: hda - fixup for the bass speaker on Lenovo Carbon X1 7th gen
ALSA: hda: hdmi - preserve non-MST PCM routing for Intel platforms
ALSA: hda: hdmi - fix kernel oops caused by invalid PCM idx
ALSA: hda/realtek - Fix inverted bass GPIO pin on Acer 8951G
ALSA: hda/realtek - Dell headphone has noise on unmute for ALC236
ALSA: hda: hdmi - fix regression in connect list handling
ALSA: aloop: Avoid pointer dereference before null-check
ALSA: hda/hdmi - enable automatic runtime pm for AMD HDMI codecs by default
ALSA: hda/hdmi - enable runtime pm for newer AMD display audio
ALSA: hda/hdmi - Add new pci ids for AMD GPU display audio
ALSA: hda/hdmi - fix vgaswitcheroo detection for AMD
syzkaller reported an invalid access in PCM OSS read, and this seems
to be an overflow of the internal buffer allocated for a plugin.
Since the rate plugin adjusts its transfer size dynamically, the
calculation for the chained plugin might be bigger than the given
buffer size in some extreme cases, which lead to such an buffer
overflow as caught by KASAN.
Fix it by limiting the max transfer size properly by checking against
the destination size in each plugin transfer callback.
Reported-by: syzbot+f153bde47a62e0b05f83@syzkaller.appspotmail.com
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20191204144824.17801-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
The SNDCTL_* and SOUND_* commands are the old OSS user interface.
I checked all the sound ioctl commands listed in fs/compat_ioctl.c
to see if we still need the translation handlers. Here is what I
found:
- sound/oss/ is (almost) gone from the kernel, this is what actually
needed all the translations
- The ALSA emulation for OSS correctly handles all compat_ioctl
commands already.
- sound/oss/dmasound/ is the last holdout of the original OSS code,
this is only used on arch/m68k, which has no 64-bit mode and
hence needs no compat handlers
- arch/um/drivers/hostaudio_kern.c may run in 64-bit mode with
32-bit x86 user space underneath it. This rare corner case is
the only one that still needs the compat handlers.
By adding a simple redirect of .compat_ioctl to .unlocked_ioctl in the
UML driver, we can remove all the COMPATIBLE_IOCTL() annotations without
a change in functionality. For completeness, I'm adding the same thing
to the dmasound file, knowing that it makes no difference.
The compat_ioctl list contains one comment about SNDCTL_DSP_MAPINBUF and
SNDCTL_DSP_MAPOUTBUF, which actually would need a translation handler
if implemented. However, the native implementation just returns -EINVAL,
so we don't care.
Reviewed-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
This is a very big update, mainly thanks to Morimoto-san's refactoring
work and some fairly large new drivers.
- Lots more work on moving towards a component based framework from
Morimoto-san.
- Support for force disconnecting muxes from Jerome Brunet.
- New drivers for Cirrus Logic CS47L35, CS47L85 and CS47L90, Conexant
CX2072X, Realtek RT1011 and RT1308.
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Merge tag 'asoc-v5.3' of https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into for-linus
ASoC: Updates for v5.3
This is a very big update, mainly thanks to Morimoto-san's refactoring
work and some fairly large new drivers.
- Lots more work on moving towards a component based framework from
Morimoto-san.
- Support for force disconnecting muxes from Jerome Brunet.
- New drivers for Cirrus Logic CS47L35, CS47L85 and CS47L90, Conexant
CX2072X, Realtek RT1011 and RT1308.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Based on 1 normalized pattern(s):
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version this program is distributed in the
hope that it will be useful but without any warranty without even
the implied warranty of merchantability or fitness for a particular
purpose see the gnu general public license for more details you
should have received a copy of the gnu general public license along
with this program if not write to the free software foundation inc
59 temple place suite 330 boston ma 02111 1307 usa
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-or-later
has been chosen to replace the boilerplate/reference in 1334 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070033.113240726@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Make use of the struct_size() helper instead of an open-coded version
in order to avoid any potential type mistakes, in particular in the
context in which this code is being used.
So, replace the following form:
sizeof(struct rate_priv) + src_format->channels * sizeof(struct rate_channel)
with:
struct_size(data, channels, src_format->channels)
This code was detected with the help of Coccinelle.
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
The snd_cards[] array holds the card pointers that have been currently
registered, and it's exported for the external modules that may need
to refer a card object. But accessing to this array can be racy
against the driver probe or removal, as the card registration or free
may happen concurrently.
This patch gets rid of the direct access to snd_cards[] array and
provides a helper function to give the card object from the index
number with a refcount management. Then the caller can access to the
given card object safely, and releases it via snd_card_unref().
While we're at it, add a proper comment to snd_card_unref() and make
it an inlined function for type-safety, too.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
The PCM OSS emulation converts and transfers the data on the fly via
"plugins". The data is converted over the dynamically allocated
buffer for each plugin, and recently syzkaller caught OOB in this
flow.
Although the bisection by syzbot pointed out to the commit
65766ee0bf ("ALSA: oss: Use kvzalloc() for local buffer
allocations"), this is merely a commit to replace vmalloc() with
kvmalloc(), hence it can't be the cause. The further debug action
revealed that this happens in the case where a slave PCM doesn't
support only the stereo channels while the OSS stream is set up for a
mono channel. Below is a brief explanation:
At each OSS parameter change, the driver sets up the PCM hw_params
again in snd_pcm_oss_change_params_lock(). This is also the place
where plugins are created and local buffers are allocated. The
problem is that the plugins are created before the final hw_params is
determined. Namely, two snd_pcm_hw_param_near() calls for setting the
period size and periods may influence on the final result of channels,
rates, etc, too, while the current code has already created plugins
beforehand with the premature values. So, the plugin believes that
channels=1, while the actual I/O is with channels=2, which makes the
driver reading/writing over the allocated buffer size.
The fix is simply to move the plugin allocation code after the final
hw_params call.
Reported-by: syzbot+d4503ae45b65c5bc1194@syzkaller.appspotmail.com
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
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>
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>
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>
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>
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>
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>
