Takashi Iwai ba3021b2c7 ALSA: timer: Fix missing queue indices reset at SNDRV_TIMER_IOCTL_SELECT ... snd_timer_user_tselect() reallocates the queue buffer dynamically, but it forgot to reset its indices. Since the read may happen concurrently with ioctl and snd_timer_user_tselect() allocates the buffer via kmalloc(), this may lead to the leak of uninitialized kernel-space data, as spotted via KMSAN: BUG: KMSAN: use of unitialized memory in snd_timer_user_read+0x6c4/0xa10 CPU: 0 PID: 1037 Comm: probe Not tainted 4.11.0-rc5+ #2739 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:16 dump_stack+0x143/0x1b0 lib/dump_stack.c:52 kmsan_report+0x12a/0x180 mm/kmsan/kmsan.c:1007 kmsan_check_memory+0xc2/0x140 mm/kmsan/kmsan.c:1086 copy_to_user ./arch/x86/include/asm/uaccess.h:725 snd_timer_user_read+0x6c4/0xa10 sound/core/timer.c:2004 do_loop_readv_writev fs/read_write.c:716 __do_readv_writev+0x94c/0x1380 fs/read_write.c:864 do_readv_writev fs/read_write.c:894 vfs_readv fs/read_write.c:908 do_readv+0x52a/0x5d0 fs/read_write.c:934 SYSC_readv+0xb6/0xd0 fs/read_write.c:1021 SyS_readv+0x87/0xb0 fs/read_write.c:1018 This patch adds the missing reset of queue indices. Together with the previous fix for the ioctl/read race, we cover the whole problem. Reported-by: Alexander Potapenko <glider@google.com> Tested-by: Alexander Potapenko <glider@google.com> Cc: <stable@vger.kernel.org> Signed-off-by: Takashi Iwai <tiwai@suse.de>		2017-06-07 10:25:23 +02:00
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oss	sched/headers: Prepare to move signal wakeup & sigpending methods from <linux/sched.h> into <linux/sched/signal.h>	2017-03-02 08:42:32 +01:00
seq	ALSA: seq: Don't break snd_use_lock_sync() loop by timeout	2017-04-13 14:13:25 +02:00
compress_offload.c
control_compat.c
control.c	sched/headers: Prepare to move signal wakeup & sigpending methods from <linux/sched.h> into <linux/sched/signal.h>	2017-03-02 08:42:32 +01:00
ctljack.c
device.c
hrtimer.c
hwdep_compat.c
hwdep.c	sched/headers: Prepare to move signal wakeup & sigpending methods from <linux/sched.h> into <linux/sched/signal.h>	2017-03-02 08:42:32 +01:00
info_oss.c
info.c
init.c
isadma.c
jack.c
Kconfig
Makefile
memalloc.c
memory.c
misc.c
pcm_compat.c
pcm_dmaengine.c
pcm_drm_eld.c
pcm_iec958.c
pcm_lib.c	sched/headers: Prepare to move signal wakeup & sigpending methods from <linux/sched.h> into <linux/sched/signal.h>	2017-03-02 08:42:32 +01:00
pcm_memory.c
pcm_misc.c
pcm_native.c	sched/headers: Prepare to move signal wakeup & sigpending methods from <linux/sched.h> into <linux/sched/signal.h>	2017-03-02 08:42:32 +01:00
pcm_timer.c
pcm_trace.h
pcm.c
rawmidi_compat.c
rawmidi.c	sched/headers: Prepare to move signal wakeup & sigpending methods from <linux/sched.h> into <linux/sched/signal.h>	2017-03-02 08:42:32 +01:00
sgbuf.c
sound_oss.c
sound.c
timer_compat.c
timer.c	ALSA: timer: Fix missing queue indices reset at SNDRV_TIMER_IOCTL_SELECT	2017-06-07 10:25:23 +02:00
vmaster.c