linux-stable.git/sound, branch v3.18.76

ALSA: seq: Fix missing NULL check at remove_events ioctl

2017-10-18T07:15:16+00:00

commit 030e2c78d3a91dd0d27fef37e91950dde333eba1 upstream.

snd_seq_ioctl_remove_events() calls snd_seq_fifo_clear()
unconditionally even if there is no FIFO assigned, and this leads to
an Oops due to NULL dereference.  The fix is just to add a proper NULL
check.

Reported-by: Dmitry Vyukov 
Tested-by: Dmitry Vyukov 
Signed-off-by: Takashi Iwai 
Cc: Mark Salyzyn 
Cc: Dmitry Vyukov 
Signed-off-by: Greg Kroah-Hartman

ALSA: caiaq: Fix stray URB at probe error path

2017-10-18T07:15:16+00:00

commit 99fee508245825765ff60155fed43f970ff83a8f upstream.

caiaq driver doesn't kill the URB properly at its error path during
the probe, which may lead to a use-after-free error later.  This patch
addresses it.

Reported-by: Johan Hovold 
Reviewed-by: Johan Hovold 
Signed-off-by: Takashi Iwai 
Signed-off-by: Greg Kroah-Hartman

ALSA: seq: Fix copy_from_user() call inside lock

2017-10-18T07:15:16+00:00

commit 5803b023881857db32ffefa0d269c90280a67ee0 upstream.

The event handler in the virmidi sequencer code takes a read-lock for
the linked list traverse, while it's calling snd_seq_dump_var_event()
in the loop.  The latter function may expand the user-space data
depending on the event type.  It eventually invokes copy_from_user(),
which might be a potential dead-lock.

The sequencer core guarantees that the user-space data is passed only
with atomic=0 argument, but snd_virmidi_dev_receive_event() ignores it
and always takes read-lock().  For avoiding the problem above, this
patch introduces rwsem for non-atomic case, while keeping rwlock for
atomic case.

Also while we're at it: the superfluous irq flags is dropped in
snd_virmidi_input_open().

Reported-by: Jia-Ju Bai 
Signed-off-by: Takashi Iwai 
Signed-off-by: Greg Kroah-Hartman

ALSA: seq: Fix use-after-free at creating a port

2017-10-18T07:15:16+00:00

commit 71105998845fb012937332fe2e806d443c09e026 upstream.

There is a potential race window opened at creating and deleting a
port via ioctl, as spotted by fuzzing.  snd_seq_create_port() creates
a port object and returns its pointer, but it doesn't take the
refcount, thus it can be deleted immediately by another thread.
Meanwhile, snd_seq_ioctl_create_port() still calls the function
snd_seq_system_client_ev_port_start() with the created port object
that is being deleted, and this triggers use-after-free like:

 BUG: KASAN: use-after-free in snd_seq_ioctl_create_port+0x504/0x630 [snd_seq] at addr ffff8801f2241cb1
 =============================================================================
 BUG kmalloc-512 (Tainted: G    B          ): kasan: bad access detected
 -----------------------------------------------------------------------------
 INFO: Allocated in snd_seq_create_port+0x94/0x9b0 [snd_seq] age=1 cpu=3 pid=4511
 	___slab_alloc+0x425/0x460
 	__slab_alloc+0x20/0x40
  	kmem_cache_alloc_trace+0x150/0x190
	snd_seq_create_port+0x94/0x9b0 [snd_seq]
	snd_seq_ioctl_create_port+0xd1/0x630 [snd_seq]
 	snd_seq_do_ioctl+0x11c/0x190 [snd_seq]
 	snd_seq_ioctl+0x40/0x80 [snd_seq]
 	do_vfs_ioctl+0x54b/0xda0
 	SyS_ioctl+0x79/0x90
 	entry_SYSCALL_64_fastpath+0x16/0x75
 INFO: Freed in port_delete+0x136/0x1a0 [snd_seq] age=1 cpu=2 pid=4717
 	__slab_free+0x204/0x310
 	kfree+0x15f/0x180
 	port_delete+0x136/0x1a0 [snd_seq]
 	snd_seq_delete_port+0x235/0x350 [snd_seq]
 	snd_seq_ioctl_delete_port+0xc8/0x180 [snd_seq]
 	snd_seq_do_ioctl+0x11c/0x190 [snd_seq]
 	snd_seq_ioctl+0x40/0x80 [snd_seq]
 	do_vfs_ioctl+0x54b/0xda0
 	SyS_ioctl+0x79/0x90
 	entry_SYSCALL_64_fastpath+0x16/0x75
 Call Trace:
  [] dump_stack+0x63/0x82
  [] print_trailer+0xfb/0x160
  [] object_err+0x34/0x40
  [] kasan_report.part.2+0x223/0x520
  [] ? snd_seq_ioctl_create_port+0x504/0x630 [snd_seq]
  [] __asan_report_load1_noabort+0x2e/0x30
  [] snd_seq_ioctl_create_port+0x504/0x630 [snd_seq]
  [] ? snd_seq_ioctl_delete_port+0x180/0x180 [snd_seq]
  [] ? taskstats_exit+0xbc0/0xbc0
  [] snd_seq_do_ioctl+0x11c/0x190 [snd_seq]
  [] snd_seq_ioctl+0x40/0x80 [snd_seq]
  [] ? acct_account_cputime+0x63/0x80
  [] do_vfs_ioctl+0x54b/0xda0
  .....

We may fix this in a few different ways, and in this patch, it's fixed
simply by taking the refcount properly at snd_seq_create_port() and
letting the caller unref the object after use.  Also, there is another
potential use-after-free by sprintf() call in snd_seq_create_port(),
and this is moved inside the lock.

This fix covers CVE-2017-15265.

Reported-and-tested-by: Michael23 Yu 
Suggested-by: Linus Torvalds 
Signed-off-by: Takashi Iwai 
Signed-off-by: Greg Kroah-Hartman

ALSA: usb-audio: Kill stray URB at exiting

2017-10-18T07:15:16+00:00

commit 124751d5e63c823092060074bd0abaae61aaa9c4 upstream.

USB-audio driver may leave a stray URB for the mixer interrupt when it
exits by some error during probe.  This leads to a use-after-free
error as spotted by syzkaller like:
  ==================================================================
  BUG: KASAN: use-after-free in snd_usb_mixer_interrupt+0x604/0x6f0
  Call Trace:
   
   __dump_stack lib/dump_stack.c:16
   dump_stack+0x292/0x395 lib/dump_stack.c:52
   print_address_description+0x78/0x280 mm/kasan/report.c:252
   kasan_report_error mm/kasan/report.c:351
   kasan_report+0x23d/0x350 mm/kasan/report.c:409
   __asan_report_load8_noabort+0x19/0x20 mm/kasan/report.c:430
   snd_usb_mixer_interrupt+0x604/0x6f0 sound/usb/mixer.c:2490
   __usb_hcd_giveback_urb+0x2e0/0x650 drivers/usb/core/hcd.c:1779
   ....

  Allocated by task 1484:
   save_stack_trace+0x1b/0x20 arch/x86/kernel/stacktrace.c:59
   save_stack+0x43/0xd0 mm/kasan/kasan.c:447
   set_track mm/kasan/kasan.c:459
   kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:551
   kmem_cache_alloc_trace+0x11e/0x2d0 mm/slub.c:2772
   kmalloc ./include/linux/slab.h:493
   kzalloc ./include/linux/slab.h:666
   snd_usb_create_mixer+0x145/0x1010 sound/usb/mixer.c:2540
   create_standard_mixer_quirk+0x58/0x80 sound/usb/quirks.c:516
   snd_usb_create_quirk+0x92/0x100 sound/usb/quirks.c:560
   create_composite_quirk+0x1c4/0x3e0 sound/usb/quirks.c:59
   snd_usb_create_quirk+0x92/0x100 sound/usb/quirks.c:560
   usb_audio_probe+0x1040/0x2c10 sound/usb/card.c:618
   ....

  Freed by task 1484:
   save_stack_trace+0x1b/0x20 arch/x86/kernel/stacktrace.c:59
   save_stack+0x43/0xd0 mm/kasan/kasan.c:447
   set_track mm/kasan/kasan.c:459
   kasan_slab_free+0x72/0xc0 mm/kasan/kasan.c:524
   slab_free_hook mm/slub.c:1390
   slab_free_freelist_hook mm/slub.c:1412
   slab_free mm/slub.c:2988
   kfree+0xf6/0x2f0 mm/slub.c:3919
   snd_usb_mixer_free+0x11a/0x160 sound/usb/mixer.c:2244
   snd_usb_mixer_dev_free+0x36/0x50 sound/usb/mixer.c:2250
   __snd_device_free+0x1ff/0x380 sound/core/device.c:91
   snd_device_free_all+0x8f/0xe0 sound/core/device.c:244
   snd_card_do_free sound/core/init.c:461
   release_card_device+0x47/0x170 sound/core/init.c:181
   device_release+0x13f/0x210 drivers/base/core.c:814
   ....

Actually such a URB is killed properly at disconnection when the
device gets probed successfully, and what we need is to apply it for
the error-path, too.

In this patch, we apply snd_usb_mixer_disconnect() at releasing.
Also introduce a new flag, disconnected, to struct usb_mixer_interface
for not performing the disconnection procedure twice.

Reported-by: Andrey Konovalov 
Tested-by: Andrey Konovalov 
Signed-off-by: Takashi Iwai 
Signed-off-by: Greg Kroah-Hartman

ALSA: usx2y: Suppress kernel warning at page allocation failures

2017-10-12T07:18:03+00:00

commit 7682e399485fe19622b6fd82510b1f4551e48a25 upstream.

The usx2y driver allocates the stream read/write buffers in continuous
pages depending on the stream setup, and this may spew the kernel
warning messages with a stack trace like:
  WARNING: CPU: 1 PID: 1846 at mm/page_alloc.c:3883
  __alloc_pages_slowpath+0x1ef2/0x2d70
  Modules linked in:
  CPU: 1 PID: 1846 Comm: kworker/1:2 Not tainted
  ....

It may confuse user as if it were any serious error, although this is
no fatal error and the driver handles the error case gracefully.
Since the driver has already some sanity check of the given size (128
and 256 pages), it can't pass any crazy value.  So it's merely page
fragmentation.

This patch adds __GFP_NOWARN to each caller for suppressing such
kernel warnings.  The original issue was spotted by syzkaller.

Reported-by: Andrey Konovalov 
Tested-by: Andrey Konovalov 
Signed-off-by: Takashi Iwai 
Signed-off-by: Greg Kroah-Hartman

ALSA: usb-audio: Check out-of-bounds access by corrupted buffer descriptor

2017-10-12T07:18:01+00:00

commit bfc81a8bc18e3c4ba0cbaa7666ff76be2f998991 upstream.

When a USB-audio device receives a maliciously adjusted or corrupted
buffer descriptor, the USB-audio driver may access an out-of-bounce
value at its parser.  This was detected by syzkaller, something like:

  BUG: KASAN: slab-out-of-bounds in usb_audio_probe+0x27b2/0x2ab0
  Read of size 1 at addr ffff88006b83a9e8 by task kworker/0:1/24
  CPU: 0 PID: 24 Comm: kworker/0:1 Not tainted 4.14.0-rc1-42251-gebb2c2437d80 #224
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
  Workqueue: usb_hub_wq hub_event
  Call Trace:
   __dump_stack lib/dump_stack.c:16
   dump_stack+0x292/0x395 lib/dump_stack.c:52
   print_address_description+0x78/0x280 mm/kasan/report.c:252
   kasan_report_error mm/kasan/report.c:351
   kasan_report+0x22f/0x340 mm/kasan/report.c:409
   __asan_report_load1_noabort+0x19/0x20 mm/kasan/report.c:427
   snd_usb_create_streams sound/usb/card.c:248
   usb_audio_probe+0x27b2/0x2ab0 sound/usb/card.c:605
   usb_probe_interface+0x35d/0x8e0 drivers/usb/core/driver.c:361
   really_probe drivers/base/dd.c:413
   driver_probe_device+0x610/0xa00 drivers/base/dd.c:557
   __device_attach_driver+0x230/0x290 drivers/base/dd.c:653
   bus_for_each_drv+0x161/0x210 drivers/base/bus.c:463
   __device_attach+0x26e/0x3d0 drivers/base/dd.c:710
   device_initial_probe+0x1f/0x30 drivers/base/dd.c:757
   bus_probe_device+0x1eb/0x290 drivers/base/bus.c:523
   device_add+0xd0b/0x1660 drivers/base/core.c:1835
   usb_set_configuration+0x104e/0x1870 drivers/usb/core/message.c:1932
   generic_probe+0x73/0xe0 drivers/usb/core/generic.c:174
   usb_probe_device+0xaf/0xe0 drivers/usb/core/driver.c:266
   really_probe drivers/base/dd.c:413
   driver_probe_device+0x610/0xa00 drivers/base/dd.c:557
   __device_attach_driver+0x230/0x290 drivers/base/dd.c:653
   bus_for_each_drv+0x161/0x210 drivers/base/bus.c:463
   __device_attach+0x26e/0x3d0 drivers/base/dd.c:710
   device_initial_probe+0x1f/0x30 drivers/base/dd.c:757
   bus_probe_device+0x1eb/0x290 drivers/base/bus.c:523
   device_add+0xd0b/0x1660 drivers/base/core.c:1835
   usb_new_device+0x7b8/0x1020 drivers/usb/core/hub.c:2457
   hub_port_connect drivers/usb/core/hub.c:4903
   hub_port_connect_change drivers/usb/core/hub.c:5009
   port_event drivers/usb/core/hub.c:5115
   hub_event+0x194d/0x3740 drivers/usb/core/hub.c:5195
   process_one_work+0xc7f/0x1db0 kernel/workqueue.c:2119
   worker_thread+0x221/0x1850 kernel/workqueue.c:2253
   kthread+0x3a1/0x470 kernel/kthread.c:231
   ret_from_fork+0x2a/0x40 arch/x86/entry/entry_64.S:431

This patch adds the checks of out-of-bounce accesses at appropriate
places and bails out when it goes out of the given buffer.

Reported-by: Andrey Konovalov 
Tested-by: Andrey Konovalov 
Signed-off-by: Takashi Iwai 
Signed-off-by: Greg Kroah-Hartman

ALSA: au88x0: avoid theoretical uninitialized access

2017-10-08T08:11:22+00:00

commit 13f99ebdd602ebdafb909e15ec6ffb1e34690167 upstream.

The latest gcc-7.0.1 snapshot points out that we if nr_ch is zero, we never
initialize some variables:

sound/pci/au88x0/au88x0_core.c: In function 'vortex_adb_allocroute':
sound/pci/au88x0/au88x0_core.c:2304:68: error: 'mix[0]' may be used uninitialized in this function [-Werror=maybe-uninitialized]
sound/pci/au88x0/au88x0_core.c:2305:58: error: 'src[0]' may be used uninitialized in this function [-Werror=maybe-uninitialized]

I assume this can never happen in practice, but adding a check here doesn't
hurt either and avoids the warning. The code has been unchanged since
the start of git history.

Signed-off-by: Arnd Bergmann 
Signed-off-by: Takashi Iwai 
Signed-off-by: Greg Kroah-Hartman

ALSA: msnd: Optimize / harden DSP and MIDI loops

2017-09-13T21:03:47+00:00

commit 20e2b791796bd68816fa115f12be5320de2b8021 upstream.

The ISA msnd drivers have loops fetching the ring-buffer head, tail
and size values inside the loops.  Such codes are inefficient and
fragile.

This patch optimizes it, and also adds the sanity check to avoid the
endless loops.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=196131
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=196133
Signed-off-by: Takashi Iwai 
Signed-off-by: grygorii tertychnyi 
Signed-off-by: Greg Kroah-Hartman

ALSA: au88x0: Fix zero clear of stream->resources

2017-09-02T05:05:45+00:00

commit 639db596165746ca87bbcb56559b094fd9042890 upstream.

There are a few calls of memset() to stream->resources, but they all
are called in a wrong size, sizeof(unsigned char) * VORTEX_RESOURCE_LAST,
while this field is a u32 array.  This may leave the memories not
zero-cleared.

Fix it by replacing them with a simpler sizeof(stream->resources)
instead.

Reported-by: David Binderman 
Signed-off-by: Takashi Iwai 
Signed-off-by: Greg Kroah-Hartman