Takashi Iwai 6ff1a25318 ALSA: usb-audio: Fix use-after-free of usb_device at disconnect ... The usb-audio driver implements the deferred device disconnection for the device in use. In this mode, the disconnection callback returns immediately while the actual ALSA card object removal happens later when all files get closed. As Shuah reported, this code flow, however, leads to a use-after-free, detected by KASAN: BUG: KASAN: use-after-free in snd_usb_audio_free+0x134/0x160 [snd_usb_audio] at addr ffff8801c863ce10 Write of size 8 by task pulseaudio/2244 Call Trace: [<ffffffff81b31473>] dump_stack+0x67/0x94 [<ffffffff81564ef1>] kasan_object_err+0x21/0x70 [<ffffffff8156518a>] kasan_report_error+0x1fa/0x4e0 [<ffffffff81564ad7>] ? kasan_slab_free+0x87/0xb0 [<ffffffff81565733>] __asan_report_store8_noabort+0x43/0x50 [<ffffffffa0fc0f54>] ? snd_usb_audio_free+0x134/0x160 [snd_usb_audio] [<ffffffffa0fc0f54>] snd_usb_audio_free+0x134/0x160 [snd_usb_audio] [<ffffffffa0fc0fb1>] snd_usb_audio_dev_free+0x31/0x40 [snd_usb_audio] [<ffffffff8243c78a>] __snd_device_free+0x12a/0x210 [<ffffffff8243d1f5>] snd_device_free_all+0x85/0xd0 [<ffffffff8242cae4>] release_card_device+0x34/0x130 [<ffffffff81ef1846>] device_release+0x76/0x1e0 [<ffffffff81b37ad7>] kobject_release+0x107/0x370 ..... Object at ffff8801c863cc80, in cache kmalloc-2048 size: 2048 Allocated: [<ffffffff810804eb>] save_stack_trace+0x2b/0x50 [<ffffffff81564296>] save_stack+0x46/0xd0 [<ffffffff8156450d>] kasan_kmalloc+0xad/0xe0 [<ffffffff81560d1a>] kmem_cache_alloc_trace+0xfa/0x240 [<ffffffff8214ea47>] usb_alloc_dev+0x57/0xc90 [<ffffffff8216349d>] hub_event+0xf1d/0x35f0 .... Freed: [<ffffffff810804eb>] save_stack_trace+0x2b/0x50 [<ffffffff81564296>] save_stack+0x46/0xd0 [<ffffffff81564ac1>] kasan_slab_free+0x71/0xb0 [<ffffffff81560929>] kfree+0xd9/0x280 [<ffffffff8214de6e>] usb_release_dev+0xde/0x110 [<ffffffff81ef1846>] device_release+0x76/0x1e0 .... It's the code trying to clear drvdata of the assigned usb_device where the usb_device itself was already released in usb_release_dev() after the disconnect callback. This patch fixes it by checking whether the code path is via the disconnect callback, i.e. chip->shutdown flag is set. Fixes: 79289e2419 ('ALSA: usb-audio: Refer to chip->usb_id for quirks...') Reported-and-tested-by: Shuah Khan <shuahkh@osg.samsung.com> Cc: <stable@vger.kernel.org> # v4.6+ Signed-off-by: Takashi Iwai <tiwai@suse.de>		2016-11-14 22:05:04 +01:00
..
6fire
bcd2000
caiaq	ALSA: usb: caiaq: audio: don't print error when allocating urb fails	2016-08-11 23:05:57 +02:00
hiface
line6	ALSA: line6: fix a crash in line6_hwdep_write()	2016-10-12 20:10:23 +02:00
misc
usx2y
card.c	ALSA: usb-audio: Fix use-after-free of usb_device at disconnect	2016-11-14 22:05:04 +01:00
card.h	ALSA: usb: use TEAC UD-H01 quirk for more devices	2016-08-22 11:39:56 +02:00
clock.c
clock.h
debug.h
endpoint.c	ALSA: usb: fine-tune Tenor error compensation value	2016-08-22 11:40:04 +02:00
endpoint.h
format.c	ALSA: usb-audio: rmove print for failure of kmalloc	2016-08-22 11:41:02 +02:00
format.h
helper.c
helper.h
Kconfig
Makefile
midi.c
midi.h
mixer_maps.c
mixer_quirks.c	ALSA: usb-audio: Extend DragonFly dB scale quirk to cover other variants	2016-09-23 08:32:18 +02:00
mixer_quirks.h
mixer_scarlett.c
mixer_scarlett.h
mixer.c
mixer.h
pcm.c
pcm.h
power.h
proc.c
proc.h
quirks-table.h	ALSA: usb-audio: Add quirk for Syntek STK1160	2016-10-27 12:07:19 +02:00
quirks.c	Merge branch 'for-linus' into for-next	2016-09-11 09:33:12 +02:00
quirks.h
stream.c
stream.h
usbaudio.h