commit ae769d3556644888c964635179ef192995f40793 upstream.
The recent fix for the OOB access in PCM OSS plugins (commit
f2ecf903ef06: "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.
Fixes: f2ecf903ef06 ("ALSA: pcm: oss: Avoid plugin buffer overflow")
Tested-and-reported-by: Jari Ruusu <jari.ruusu@gmail.com>
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20200403072515.25539-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 5461e0530c222129dfc941058be114b5cbc00837 upstream.
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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit f2ecf903ef06eb1bbbfa969db9889643d487e73a upstream.
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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 4384f167ce5fa7241b61bb0984d651bc528ddebe upstream.
The virmidi driver handles sysex event exceptionally in a short-cut
snd_seq_dump_var_event() call, but this missed the reset of the
running status. As a result, it may lead to an incomplete command
right after the sysex when an event with the same running status was
queued.
Fix it by clearing the running status properly via alling
snd_midi_event_reset_decode() for that code path.
Reported-by: Andreas Steinmetz <ast@domdv.de>
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/3b4a4e0f232b7afbaf0a843f63d0e538e3029bfd.camel@domdv.de
Link: https://lore.kernel.org/r/20200316090506.23966-2-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit dc7497795e014d84699c3b8809ed6df35352dd74 upstream.
snd_seq_check_queue() passes the current tick and time of the given
queue as a pointer to snd_seq_prioq_cell_out(), but those might be
updated concurrently by the seq timer update.
Fix it by retrieving the current tick and time via the proper helper
functions at first, and pass those values to snd_seq_prioq_cell_out()
later in the loops.
snd_seq_timer_get_cur_time() takes a new argument and adjusts with the
current system time only when it's requested so; this update isn't
needed for snd_seq_check_queue(), as it's called either from the
interrupt handler or right after queuing.
Also, snd_seq_timer_get_cur_tick() is changed to read the value in the
spinlock for the concurrency, too.
Reported-by: syzbot+fd5e0eaa1a32999173b2@syzkaller.appspotmail.com
Link: https://lore.kernel.org/r/20200214111316.26939-3-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit bb51e669fa49feb5904f452b2991b240ef31bc97 upstream.
The queue flags are represented in bit fields and the concurrent
access may result in unexpected results. Although the current code
should be mostly OK as it's only reading a field while writing other
fields as KCSAN reported, it's safer to cover both with a proper
spinlock protection.
This patch fixes the possible concurrent read by protecting with
q->owner_lock. Also the queue owner field is protected as well since
it's the field to be protected by the lock itself.
Reported-by: syzbot+65c6c92d04304d0a8efc@syzkaller.appspotmail.com
Reported-by: syzbot+e60ddfa48717579799dd@syzkaller.appspotmail.com
Link: https://lore.kernel.org/r/20200214111316.26939-2-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit d61fe22c2ae42d9fd76c34ef4224064cca4b04b0 ]
A design of ALSA control core allows applications to execute three
operations for TLV feature; read, write and command. Furthermore, it
allows driver developers to process the operations by two ways; allocated
array or callback function. In the former, read operation is just allowed,
thus developers uses the latter when device driver supports variety of
models or the target model is expected to dynamically change information
stored in TLV container.
The core also allows applications to lock any element so that the other
applications can't perform write operation to the element for element
value and TLV information. When the element is locked, write and command
operation for TLV information are prohibited as well as element value.
Any read operation should be allowed in the case.
At present, when an element has callback function for TLV information,
TLV read operation returns EPERM if the element is locked. On the
other hand, the read operation is success when an element has allocated
array for TLV information. In both cases, read operation is success for
element value expectedly.
This commit fixes the bug. This change can be backported to v4.14
kernel or later.
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Reviewed-by: Jaroslav Kysela <perex@perex.cz>
Link: https://lore.kernel.org/r/20191223093347.15279-1-o-takashi@sakamocchi.jp
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 60adcfde92fa40fcb2dbf7cc52f9b096e0cd109a upstream.
snd_seq_info_timer_read() reads the information of the timer assigned
for each queue, but it's done in a racy way which may lead to UAF as
spotted by syzkaller.
This patch applies the missing q->timer_mutex lock while accessing the
timer object as well as a slight code change to adapt the standard
coding style.
Reported-by: syzbot+2b2ef983f973e5c40943@syzkaller.appspotmail.com
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20200115203733.26530-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit fdea53fe5de532969a332d6e5e727f2ad8bf084d ]
The fuzzer tries to open the timer instances as much as possible, and
this may cause a system hiccup easily. We've already introduced the
cap for the max number of available instances for the h/w timers, and
we should put such a limit also to the slave timers, too.
This patch introduces the limit to the multiple opened slave timers.
The upper limit is hard-coded to 1000 for now, which should suffice
for any practical usages up to now.
Link: https://lore.kernel.org/r/20191106154257.5853-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit add9d56d7b3781532208afbff5509d7382fb6efe upstream.
The current PCM code doesn't initialize explicitly the buffers
allocated for PCM streams, hence it might leak some uninitialized
kernel data or previous stream contents by mmapping or reading the
buffer before actually starting the stream.
Since this is a common problem, this patch simply adds the clearance
of the buffer data at hw_params callback. Although this does only
zero-clear no matter which format is used, which doesn't mean the
silence for some formats, but it should be OK because the intention is
just to clear the previous data on the buffer.
Reported-by: Lionel Koenig <lionel.koenig@gmail.com>
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20191211155742.3213-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 4cc8d6505ab82db3357613d36e6c58a297f57f7c upstream.
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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit f5cdc9d4003a2f66ea57b3edd3e04acc2b1a4439 ]
If the nullity check for `substream->runtime` is outside of the lock
region, it is possible to have a null runtime in the critical section
if snd_pcm_detach_substream is called right before the lock.
Signed-off-by: paulhsia <paulhsia@chromium.org>
Link: https://lore.kernel.org/r/20191112171715.128727-2-paulhsia@chromium.org
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit d3645b055399538415586ebaacaedebc1e5899b0 ]
Parameter fragments and fragment_size are type of u32. U32_MAX is
the correct check.
Signed-off-by: Xiaojun Sang <xsang@codeaurora.org>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Acked-by: Vinod Koul <vkoul@kernel.org>
Link: https://lore.kernel.org/r/20191021095432.5639-1-srinivas.kandagatla@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit b8e131542b47b81236ecf6768c923128e1f5db6e ]
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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 6f128fa41f310e1f39ebcea9621d2905549ecf52 ]
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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit e7af6307a8a54f0b873960b32b6a644f2d0fbd97 upstream.
The clean up commit 41672c0c24a6 ("ALSA: timer: Simplify error path in
snd_timer_open()") unified the error handling code paths with the
standard goto, but it introduced a subtle bug: the timer instance is
stored in snd_timer_open() incorrectly even if it returns an error.
This may eventually lead to UAF, as spotted by fuzzer.
The culprit is the snd_timer_open() code checks the
SNDRV_TIMER_IFLG_EXCLUSIVE flag with the common variable timeri.
This variable is supposed to be the newly created instance, but we
(ab-)used it for a temporary check before the actual creation of a
timer instance. After that point, there is another check for the max
number of instances, and it bails out if over the threshold. Before
the refactoring above, it worked fine because the code returned
directly from that point. After the refactoring, however, it jumps to
the unified error path that stores the timeri variable in return --
even if it returns an error. Unfortunately this stored value is kept
in the caller side (snd_timer_user_tselect()) in tu->timeri. This
causes inconsistency later, as if the timer was successfully
assigned.
In this patch, we fix it by not re-using timeri variable but a
temporary variable for testing the exclusive connection, so timeri
remains NULL at that point.
Fixes: 41672c0c24a6 ("ALSA: timer: Simplify error path in snd_timer_open()")
Reported-and-tested-by: Tristan Madani <tristmd@gmail.com>
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20191106165547.23518-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit a39331867335d4a94b6165e306265c9e24aca073 ]
When a card is disconnected while in use, the system waits until all
opened files are closed then releases the card. This is done via
put_device() of the card device in each device release code.
The recently reported mutex deadlock bug happens in this code path;
snd_timer_close() for the timer device deals with the global
register_mutex and it calls put_device() there. When this timer
device is the last one, the card gets freed and it eventually calls
snd_timer_free(), which has again the protection with the global
register_mutex -- boom.
Basically put_device() call itself is race-free, so a relative simple
workaround is to move this put_device() call out of the mutex. For
achieving that, in this patch, snd_timer_close_locked() got a new
argument to store the card device pointer in return, and each caller
invokes put_device() with the returned object after the mutex unlock.
Reported-and-tested-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 41672c0c24a62699d20aab53b98d843b16483053 ]
Just a minor refactoring to use the standard goto for error paths in
snd_timer_open() instead of open code. The first mutex_lock() is
moved to the beginning of the function to make the code clearer.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 75545304eba6a3d282f923b96a466dc25a81e359 upstream.
The input pool of a client might be deleted via the resize ioctl, the
the access to it should be covered by the proper locks. Currently the
only missing place is the call in snd_seq_ioctl_get_client_pool(), and
this patch papers over it.
Reported-by: syzbot+4a75454b9ca2777f35c7@syzkaller.appspotmail.com
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 3b8179944cb0dd53e5223996966746cdc8a60657 ]
Draining makes little sense in the situation of hardware overrun, as the
hardware will have consumed all its available samples. Additionally,
draining whilst the stream is paused would presumably get stuck as no
data is being consumed on the DSP side.
Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Acked-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit a70ab8a8645083f3700814e757f2940a88b7ef88 ]
Partial drain and next track are intended for gapless playback and
don't really have an obvious interpretation for a capture stream, so
makes sense to not allow those operations on capture streams.
Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Acked-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 26c3f1542f5064310ad26794c09321780d00c57d ]
Currently, whilst in SNDRV_PCM_STATE_OPEN it is possible to call
snd_compr_stop, snd_compr_drain and snd_compr_partial_drain, which
allow a transition to SNDRV_PCM_STATE_SETUP. The stream should
only be able to move to the setup state once it has received a
SNDRV_COMPRESS_SET_PARAMS ioctl. Fix this issue by not allowing
those ioctls whilst in the open state.
Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Acked-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 4475f8c4ab7b248991a60d9c02808dbb813d6be8 ]
A previous fix to the stop handling on compressed capture streams causes
some knock on issues. The previous fix updated snd_compr_drain_notify to
set the state back to PREPARED for capture streams. This causes some
issues however as the handling for snd_compr_poll differs between the
two states and some user-space applications were relying on the poll
failing after the stream had been stopped.
To correct this regression whilst still fixing the original problem the
patch was addressing, update the capture handling to skip the PREPARED
state rather than skipping the SETUP state as it has done until now.
Fixes: 4f2ab5e1d13d ("ALSA: compress: Fix stop handling on compressed capture streams")
Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Acked-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit ede34f397ddb063b145b9e7d79c6026f819ded13 upstream.
The fix for the racy writes and ioctls to sequencer widened the
application of client->ioctl_mutex to the whole write loop. Although
it does unlock/relock for the lengthy operation like the event dup,
the loop keeps the ioctl_mutex for the whole time in other
situations. This may take quite long time if the user-space would
give a huge buffer, and this is a likely cause of some weird behavior
spotted by syzcaller fuzzer.
This patch puts a simple workaround, just adding a mutex break in the
loop when a large number of events have been processed. This
shouldn't hit any performance drop because the threshold is set high
enough for usual operations.
Fixes: 7bd8009156 ("ALSA: seq: More protection for concurrent write and ioctl races")
Reported-by: syzbot+97aae04ce27e39cbfca9@syzkaller.appspotmail.com
Reported-by: syzbot+4c595632b98bb8ffcc66@syzkaller.appspotmail.com
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit c3ea60c231446663afd6ea1054da6b7f830855ca upstream.
There are two occurrances of a call to snd_seq_oss_fill_addr where
the dest_client and dest_port arguments are in the wrong order. Fix
this by swapping them around.
Addresses-Coverity: ("Arguments in wrong order")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit f0654ba94e33699b295ce4f3dc73094db6209035 ]
This reverts commit feb689025fbb6f0aa6297d3ddf97de945ea4ad32.
The fix attempt was incorrect, leading to the mutex deadlock through
the close of OSS sequencer client. The proper fix needs more
consideration, so let's revert it now.
Fixes: feb689025fbb ("ALSA: seq: Protect in-kernel ioctl calls with mutex")
Reported-by: syzbot+47ded6c0f23016cde310@syzkaller.appspotmail.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 2eabc5ec8ab4d4748a82050dfcb994119b983750 ]
The snd_seq_ioctl_get_subscription() retrieves the port subscriber
information as a pointer, while the object isn't protected, hence it
may be deleted before the actual reference. This race was spotted by
syzkaller and may lead to a UAF.
The fix is simply copying the data in the lookup function that
performs in the rwsem to protect against the deletion.
Reported-by: syzbot+9437020c82413d00222d@syzkaller.appspotmail.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit feb689025fbb6f0aa6297d3ddf97de945ea4ad32 ]
ALSA OSS sequencer calls the ioctl function indirectly via
snd_seq_kernel_client_ctl(). While we already applied the protection
against races between the normal ioctls and writes via the client's
ioctl_mutex, this code path was left untouched. And this seems to be
the cause of still remaining some rare UAF as spontaneously triggered
by syzkaller.
For the sake of robustness, wrap the ioctl_mutex also for the call via
snd_seq_kernel_client_ctl(), too.
Reported-by: syzbot+e4c8abb920efa77bace9@syzkaller.appspotmail.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 7c32ae35fbf9cffb7aa3736f44dec10c944ca18e upstream.
The call of unsubscribe_port() which manages the group count and
module refcount from delete_and_unsubscribe_port() looks racy; it's
not covered by the group list lock, and it's likely a cause of the
reported unbalance at port deletion. Let's move the call inside the
group list_mutex to plug the hole.
Reported-by: syzbot+e4c8abb920efa77bace9@syzkaller.appspotmail.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 8c2f870890fd28e023b0fcf49dcee333f2c8bad7 upstream.
The ALSA proc helper manages the child nodes in a linked list, but its
addition and deletion is done without any lock. This leads to a
corruption if they are operated concurrently. Usually this isn't a
problem because the proc entries are added sequentially in the driver
probe procedure itself. But the card registrations are done often
asynchronously, and the crash could be actually reproduced with
syzkaller.
This patch papers over it by protecting the link addition and deletion
with the parent's mutex. There is "access" mutex that is used for the
file access, and this can be reused for this purpose as well.
Reported-by: syzbot+48df349490c36f9f54ab@syzkaller.appspotmail.com
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 2a3f7221acddfe1caa9ff09b3a8158c39b2fdeac upstream.
There is a small race window in the card disconnection code that
allows the registration of another card with the very same card id.
This leads to a warning in procfs creation as caught by syzkaller.
The problem is that we delete snd_cards and snd_cards_lock entries at
the very beginning of the disconnection procedure. This makes the
slot available to be assigned for another card object while the
disconnection procedure is being processed. Then it becomes possible
to issue a procfs registration with the existing file name although we
check the conflict beforehand.
The fix is simply to move the snd_cards and snd_cards_lock clearances
at the end of the disconnection procedure. The references to these
entries are merely either from the global proc files like
/proc/asound/cards or from the card registration / disconnection, so
it should be fine to shift at the very end.
Reported-by: syzbot+48df349490c36f9f54ab@syzkaller.appspotmail.com
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 212ac181c158c09038c474ba68068be49caecebb upstream.
When ioctl calls are made with non-null-terminated userspace strings,
strlcpy causes an OOB-read from within strlen. Fix by changing to use
strscpy instead.
Signed-off-by: Zubin Mithra <zsm@chromium.org>
Reviewed-by: Guenter Roeck <groeck@chromium.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit d9c0b2afe820fa3b3f8258a659daee2cc71ca3ef ]
BE dai links only have internal PCM's and their substream ops may
not be set. Suspending these PCM's will result in their
ops->trigger() being invoked and cause a kernel oops.
So skip suspending PCM's if their ops are NULL.
[ NOTE: this change is required now for following the recent PCM core
change to get rid of snd_pcm_suspend() call. Since DPCM BE takes
the runtime carried from FE while keeping NULL ops, it can hit this
bug. See details at:
https://github.com/thesofproject/linux/pull/582
-- tiwai ]
Signed-off-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 113ce08109f8e3b091399e7cc32486df1cff48e7 upstream.
Currently PCM core sets each opened stream forcibly to SUSPENDED state
via snd_pcm_suspend_all() call, and the user-space is responsible for
re-triggering the resume manually either via snd_pcm_resume() or
prepare call. The scheme works fine usually, but there are corner
cases where the stream can't be resumed by that call: the streams
still in OPEN state before finishing hw_params. When they are
suspended, user-space cannot perform resume or prepare because they
haven't been set up yet. The only possible recovery is to re-open the
device, which isn't nice at all. Similarly, when a stream is in
DISCONNECTED state, it makes no sense to change it to SUSPENDED
state. Ditto for in SETUP state; which you can re-prepare directly.
So, this patch addresses these issues by filtering the PCM streams to
be suspended by checking the PCM state. When a stream is in either
OPEN, SETUP or DISCONNECTED as well as already SUSPENDED, the suspend
action is skipped.
To be noted, this problem was originally reported for the PCM runtime
PM on HD-audio. And, the runtime PM problem itself was already
addressed (although not intended) by the code refactoring commits
3d21ef0b49f8 ("ALSA: pcm: Suspend streams globally via device type PM
ops") and 17bc4815de58 ("ALSA: pci: Remove superfluous
snd_pcm_suspend*() calls"). These commits eliminated the
snd_pcm_suspend*() calls from the runtime PM suspend callback code
path, hence the racy OPEN state won't appear while runtime PM.
(FWIW, the race window is between snd_pcm_open_substream() and the
first power up in azx_pcm_open().)
Although the runtime PM issue was already "fixed", the same problem is
still present for the system PM, hence this patch is still needed.
And for stable trees, this patch alone should suffice for fixing the
runtime PM problem, too.
Reported-and-tested-by: Jon Hunter <jonathanh@nvidia.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit ca0214ee2802dd47239a4e39fb21c5b00ef61b22 upstream.
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
65766ee0bf7f ("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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit c709f14f0616482b67f9fbcb965e1493a03ff30b upstream.
dev 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/seq/oss/seq_oss_synth.c:626 snd_seq_oss_synth_make_info() warn: potential spectre issue 'dp->synths' [w] (local cap)
Fix this by sanitizing dev before using it to index dp->synths.
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://lore.kernel.org/lkml/20180423164740.GY17484@dhcp22.suse.cz/
Cc: stable@vger.kernel.org
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 2b1d9c8f87235f593826b9cf46ec10247741fff9 upstream.
info->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/rawmidi.c:604 __snd_rawmidi_info_select() warn: potential spectre issue 'rmidi->streams' [r] (local cap)
Fix this by sanitizing info->stream before using it to index
rmidi->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://lore.kernel.org/lkml/20180423164740.GY17484@dhcp22.suse.cz/
Cc: stable@vger.kernel.org
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 678e2b44c8e3fec3afc7202f1996a4500a50be93 ]
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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 94ffb030b6d31ec840bb811be455dd2e26a4f43e upstream.
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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit b51abed8355e5556886623b2772fa6b7598d2282 upstream.
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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit b888a5f713e4d17faaaff24316585a4eb07f35b7 upstream.
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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit e1a7bfe3807974e66f971f2589d4e0197ec0fced upstream.
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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 65766ee0bf7fe8b3be80e2e1c3ef54ad59b29476 upstream.
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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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>
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>
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>
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>
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>
