linux/sound/core
Takashi Iwai 9b7d869ee5 ALSA: timer: Limit max instances per timer
Currently we allow unlimited number of timer instances, and it may
bring the system hogging way too much CPU when too many timer
instances are opened and processed concurrently.  This may end up with
a soft-lockup report as triggered by syzkaller, especially when
hrtimer backend is deployed.

Since such insane number of instances aren't demanded by the normal
use case of ALSA sequencer and it merely  opens a risk only for abuse,
this patch introduces the upper limit for the number of instances per
timer backend.  As default, it's set to 1000, but for the fine-grained
timer like hrtimer, it's set to 100.

Reported-by: syzbot
Tested-by: Jérôme Glisse <jglisse@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2017-11-06 10:41:24 +01:00
..
oss sound updates for 4.13-rc1 2017-07-06 10:56:51 -07:00
seq ALSA: seq: Fix nested rwsem annotation for lockdep splat 2017-10-31 09:09:10 +01:00
compress_offload.c ALSA: compress: Remove unused variable 2017-09-18 15:45:01 +02:00
control.c ALSA: Get rid of card power_lock 2017-08-30 20:44:29 +02:00
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 ALSA: timer: Limit max instances per timer 2017-11-06 10:41:24 +01:00
hwdep.c sched/wait: Rename wait_queue_t => wait_queue_entry_t 2017-06-20 12:18:27 +02:00
hwdep_compat.c [PATCH] hwdep_compat missed __user annotations 2006-10-10 15:37:21 -07:00
info.c ALSA: core: Follow standard EXPORT_SYMBOL() declarations 2017-06-16 16:19:16 +02:00
info_oss.c ALSA: core: Follow standard EXPORT_SYMBOL() declarations 2017-06-16 16:19:16 +02:00
init.c ALSA: Get rid of card power_lock 2017-08-30 20:44:29 +02:00
isadma.c ALSA: core: Follow standard EXPORT_SYMBOL() declarations 2017-06-16 16:19:16 +02:00
jack.c ALSA: jack: Allow building the jack layer without input device 2016-02-23 09:03:07 +01:00
Kconfig ALSA: seq: Allow the modular sequencer registration 2017-06-12 08:43:33 +02:00
Makefile ALSA: seq: Allow the modular sequencer registration 2017-06-12 08:43:33 +02:00
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: Correct broken procfs set up 2017-08-25 00:05:16 +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 sound updates for 4.13-rc1 2017-07-06 10:56:51 -07:00
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: Follow standard EXPORT_SYMBOL() declarations 2017-06-16 16:18:58 +02:00
pcm_native.c ALSA: pcm: Unify ioctl functions for playback and capture streams 2017-08-30 20:44:55 +02:00
pcm_param_trace.h ALSA: pcm: use friendly name for id of PCM substream in trace print 2017-06-09 16:27:23 +02:00
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 ALSA: pcm: use %s instead of %c for format of PCM buffer tracepoints 2017-06-12 08:49:24 +02:00
rawmidi.c sound updates for 4.13-rc1 2017-07-06 10:56:51 -07:00
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 ALSA: timer: Limit max instances per timer 2017-11-06 10:41:24 +01:00
timer_compat.c ALSA: timer: Add missing mutex lock for compat ioctls 2017-10-31 08:28:16 +01:00
vmaster.c ALSA: hda - Fix incorrect TLV callback check introduced during set_fs() removal 2017-10-18 12:27:00 +02:00