WSL2-Linux-Kernel/sound/core
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
..
oss Merge branch 'for-next' into for-linus 2018-04-02 19:50:59 +02:00
seq ALSA: seq: Clear client entry before deleting else at closing 2018-03-10 17:30:01 +01:00
Kconfig ALSA: seq: Allow the modular sequencer registration 2017-06-12 08:43:33 +02:00
Makefile License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
compress_offload.c vfs: do bulk POLL* -> EPOLL* replacement 2018-02-11 14:34:03 -08:00
control.c ALSA: control: Fix a bunch of whitespace errors 2018-02-28 08:18:26 +01:00
control_compat.c ALSA: Get rid of card power_lock 2017-08-30 20:44:29 +02:00
ctljack.c ALSA: declare snd_kcontrol_new structures as const 2017-05-30 10:29:25 +02:00
device.c ALSA: core: Use %pS printk format for direct addresses 2017-09-07 10:36:02 +02:00
hrtimer.c Merge branch 'for-next' into for-linus 2017-11-13 15:43:13 +01:00
hwdep.c Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2018-01-31 09:25:20 -08:00
hwdep_compat.c [PATCH] hwdep_compat missed __user annotations 2006-10-10 15:37:21 -07:00
info.c vfs: do bulk POLL* -> EPOLL* replacement 2018-02-11 14:34:03 -08:00
info_oss.c ALSA: core: Follow standard EXPORT_SYMBOL() declarations 2017-06-16 16:19:16 +02:00
init.c ALSA: Use scnprintf() instead of snprintf() for show 2018-02-27 09:16:52 +01:00
isadma.c ALSA: core: Follow standard EXPORT_SYMBOL() declarations 2017-06-16 16:19:16 +02:00
jack.c ALSA: fix kernel-doc build warning 2017-10-30 08:10:07 +01:00
memalloc.c ALSA: core: Follow standard EXPORT_SYMBOL() declarations 2017-06-16 16:19:16 +02:00
memory.c ALSA: core: Follow standard EXPORT_SYMBOL() declarations 2017-06-16 16:19:16 +02:00
misc.c ALSA: core: Follow standard EXPORT_SYMBOL() declarations 2017-06-16 16:19:16 +02:00
pcm.c ALSA: pcm: Fix UAF at PCM release via PCM timer access 2018-04-03 08:36:40 +02:00
pcm_compat.c ALSA: pcm: Fix structure definition for X32 ABI 2017-09-22 11:23:48 +02:00
pcm_dmaengine.c ASoC: dmaengine_pcm: Add support for packed transfers 2016-04-27 17:34:11 +01:00
pcm_drm_eld.c ALSA: pcm: use helper function to refer parameter as read-only 2017-05-17 07:24:39 +02:00
pcm_iec958.c ALSA: pcm: Allow 32 bit sample format in IEC958 channel status helper 2016-04-06 14:33:38 -07:00
pcm_lib.c ALSA: pcm: Use krealloc() for resizing the rules array 2018-03-13 15:37:58 +01:00
pcm_local.h ALSA: pcm: unify codes to operate application-side position on PCM buffer 2017-06-12 08:49:22 +02:00
pcm_memory.c ALSA: pcm: Follow standard EXPORT_SYMBOL() declarations 2017-06-16 16:18:58 +02:00
pcm_misc.c ALSA: pcm: add SNDRV_PCM_FORMAT_{S,U}20 2017-11-29 09:26:33 +01:00
pcm_native.c Merge branch 'for-next' into for-linus 2018-04-02 19:50:59 +02:00
pcm_param_trace.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
pcm_timer.c ALSA: pcm: include pcm_local.h and remove some extraneous tabs 2017-05-30 18:04:47 +02:00
pcm_trace.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
rawmidi.c vfs: do bulk POLL* -> EPOLL* replacement 2018-02-11 14:34:03 -08:00
rawmidi_compat.c ALSA: rawmidi: Fix ioctls X32 ABI 2016-02-28 17:44:51 +01:00
seq_device.c ALSA: seq: Cancel pending autoload work at unbinding device 2017-09-12 12:41:20 +02:00
sgbuf.c ALSA: core: Deletion of unnecessary checks before two function calls 2014-11-21 20:06:57 +01:00
sound.c ALSA: core: Follow standard EXPORT_SYMBOL() declarations 2017-06-16 16:19:16 +02:00
sound_oss.c ALSA: core: Follow standard EXPORT_SYMBOL() declarations 2017-06-16 16:19:16 +02:00
timer.c vfs: do bulk POLL* -> EPOLL* replacement 2018-02-11 14:34:03 -08:00
timer_compat.c ALSA: timer: Remove kernel warning at compat ioctl error paths 2017-11-21 16:36:11 +01:00
vmaster.c ALSA: vmaster: Zero-clear ctl before calling slave get 2018-03-08 08:41:13 +01:00