Takashi Iwai 9f8a7658bc ALSA: timer: Fix zero-division by continue of uninitialized instance ... When a user timer instance is continued without the explicit start beforehand, the system gets eventually zero-division error like: divide error: 0000 [#1] SMP DEBUG_PAGEALLOC KASAN CPU: 1 PID: 27320 Comm: syz-executor Not tainted 4.8.0-rc3-next-20160825+ #8 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 task: ffff88003c9b2280 task.stack: ffff880027280000 RIP: 0010:[<ffffffff858e1a6c>] [< inline >] ktime_divns include/linux/ktime.h:195 RIP: 0010:[<ffffffff858e1a6c>] [<ffffffff858e1a6c>] snd_hrtimer_callback+0x1bc/0x3c0 sound/core/hrtimer.c:62 Call Trace: <IRQ> [< inline >] __run_hrtimer kernel/time/hrtimer.c:1238 [<ffffffff81504335>] __hrtimer_run_queues+0x325/0xe70 kernel/time/hrtimer.c:1302 [<ffffffff81506ceb>] hrtimer_interrupt+0x18b/0x420 kernel/time/hrtimer.c:1336 [<ffffffff8126d8df>] local_apic_timer_interrupt+0x6f/0xe0 arch/x86/kernel/apic/apic.c:933 [<ffffffff86e13056>] smp_apic_timer_interrupt+0x76/0xa0 arch/x86/kernel/apic/apic.c:957 [<ffffffff86e1210c>] apic_timer_interrupt+0x8c/0xa0 arch/x86/entry/entry_64.S:487 <EOI> ..... Although a similar issue was spotted and a fix patch was merged in commit [6b760bb2c6: ALSA: timer: fix division by zero after SNDRV_TIMER_IOCTL_CONTINUE], it seems covering only a part of iceberg. In this patch, we fix the issue a bit more drastically. Basically the continue of an uninitialized timer is supposed to be a fresh start, so we do it for user timers. For the direct snd_timer_continue() call, there is no way to pass the initial tick value, so we kick out for the uninitialized case. Reported-by: Dmitry Vyukov <dvyukov@google.com> Cc: <stable@vger.kernel.org> Signed-off-by: Takashi Iwai <tiwai@suse.de>		2016-09-08 10:45:05 +02:00
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aoa
arm	ALSA: arm: Fix empty menuconfig SND_ARM	2016-08-01 16:07:53 +02:00
atmel
core	ALSA: timer: Fix zero-division by continue of uninitialized instance	2016-09-08 10:45:05 +02:00
drivers
firewire	ALSA: fireworks: accessing to user space outside spinlock	2016-08-31 16:17:15 +02:00
hda	ALSA: hda: Fix krealloc() with __GFP_ZERO usage	2016-08-03 15:17:22 +02:00
i2c
isa
mips
oss	sound: oss: Use kernel_read_file_from_path() for mod_firmware_load()	2016-07-26 10:38:03 +02:00
parisc
pci	ALSA: hda - Enable subwoofer on Dell Inspiron 7559	2016-08-30 09:41:05 +02:00
pcmcia
ppc
sh
soc	Merge remote-tracking branches 'asoc/fix/max98371', 'asoc/fix/nau8825', 'asoc/fix/omap', 'asoc/fix/samsung', 'asoc/fix/simple' and 'asoc/fix/wm2000' into asoc-linus	2016-08-24 19:05:25 +01:00
sparc
spi
synth
usb	ALSA: usb-audio: Add sample rate inquiry quirk for B850V3 CP2114	2016-08-29 16:49:18 +02:00
ac97_bus.c
Kconfig
last.c
Makefile	sound: oss: Use kernel_read_file_from_path() for mod_firmware_load()	2016-07-26 10:38:03 +02:00
sound_core.c